Why ritualized behavior? Precaution Systems and action parsing in developmental, pathological and cultural rituals

Abstract

Ritualized behavior, intuitively recognizable by its stereotypy, rigidity, repetition, and apparent lack of rational motivation, is found in a variety of life conditions, customs, and everyday practices: in cultural rituals, whether religious or non-religious; in many children's complicated routines; in the pathology of obsessive-compulsive disorders (OCD); in normal adults around certain stages of the life-cycle, birthing in particular. Combining evidence from evolutionary anthropology, neuropsychology and neuroimaging, we propose an explanation of ritualized behavior in terms of an evolved Precaution System geared to the detection of and reaction to inferred threats to fitness. This system, distinct from fear-systems geared to respond to manifest danger, includes a repertoire of clues for potential danger as well as a repertoire of species-typical precautions. In OCD pathology, this system does not supply a negative feedback to the appraisal of potential threats, resulting in doubts about the proper performance of precautions, and repetition of action. Also, anxiety levels focus the attention on low-level gestural units of behavior rather than on the goal-related higher-level units normally used in parsing the action-flow. Normally automatized actions are submitted to cognitive control. This "swamps" working memory, an effect of which is a temporary relief from intrusions but also their long-term strengthening. Normal activation of this Precaution System explains intrusions and ritual behaviors in normal adults. Gradual calibration of the system occurs through childhood rituals. Cultural mimicry of this system's normal input makes cultural rituals attention-grabbing and compelling. A number of empirical predictions follow from this synthetic model.

Full text

Why ritualized behavior? Precaution
Systems and action parsing in
developmental, pathological
and cultural rituals
Pascal Boyer
Departments of Psychology and Anthropology
Washington University in St. Louis
St. Louis, MO 63130
pboyer@artsci.wustl.edu
Pierre Lie
´
nard
Department of Psychology, Washington University in St. Louis
St. Louis, MO 63130
plienard@artsci.wustl.edu
Abstract: Ritualized behavior, intuitively recognizable by its stereotypy, rigidity, repetition, and apparent lack of rational motivation, is
found in a variety of life conditions, customs, and everyday practices: in cultural rituals, whether religious or non-religious; in many
children’s complicated routines; in the pathology of obsessive-compulsive disorders (OCD); in normal adults around certain stages
of the life-cycle, birthing in particular. Combining evidence from evolutionary anthropology, neuropsychology and neuroimaging,
we propose an explanation of ritualized behavior in terms of an evolved Precaution System geared to the detection of and reaction
to inferred threats to fitness. This system, distinct from fear-systems geared to respond to manifest danger, includes a repertoire of
clues for potential danger as well as a repertoire of species-typical precautions. In OCD pathology, this system does not supply a
negative feedback to the appraisal of potential threats, resulting in doubts about the proper performance of precautions, and
repetition of action. Also, anxiety levels focus the attention on low-level gestural units of behavior rather than on the goal-related
higher-level units normally used in parsing the action-flow. Normally automatized actions are submitted to cognitive control. This
“swamps” working memory, an effect of which is a temporary relief from intrusions but also their long-term strengthening. Normal
activation of this Precaution System explains intrusions and ritual behaviors in normal adults. Gradual calibration of the system
occurs through childhood rituals. Cultural mimicry of this system’s normal input makes cultural rituals attention-grabbing and
compelling. A number of empirical predictions follow from this synthetic model.
Keywords: childhood ritual; compulsion; event boundaries; evolutionary psychology; obsessive-compulsive disorder; ritual; thought
intrusion
1. Ritualized behavior
In a variety of circumstances, humans
1
produce rituals,
intuitively recognizable by their stereotypy, rigidity, rep-
etition, and apparent lack of rational motivation. Behavior
of this kind is found in cultural rituals, religious or non-
religious; in the complicated routines of many children;
in the pathology of obsessive-compulsive disorders; in
normal adults around certain stages of the life-cycle,
especially during birthing. The common features of
these behaviors cry out for explanation.
We build on a variety of prior models to describe a
core psychological process that we call action ritualiza-
tion – which is only a part of individual or cultural
rituals but a crucial part. The occurrence of ritualization
depends on the conjunction of two specialized cognitive
systems. One is a motivational system geared to the
detection of and reaction to particular potential threats
to fitness. This “Hazard-Precaution System” includes a
repertoire of clues for potential danger as well as a
repertoire of species-typical precautions. The other
system might be called “Action Parsing.” It is concerned
with the division of the flow of behavior into meaningful
units. In some circumstances, specific interaction
between these systems creates ritualized actions. The
circumstances are different for individual, pathological,
and collective rituals, as we will see. But the core ritua-
lization process explains some of their common
properties.
There is no precise definition of “ritual” in any of the
three fields that deal with its typical manifestations. Cul-
tural anthropologists generally accept a very vague defi-
nition of the term as scripted, stereotypic forms of
collective action (Gluckman 1975). Ethologists use criteria
such as repetition and stereotypy (Payne 1998). Clinical
psychologists’ descriptions of OCD pathology, as in the
DSM-IV, mention “ritualistic behaviors” without more
precision (American Psychiatric Association 1995).
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1

Besides, models of the phenomenon are generally
limited to one domain of ritual. There is a large clinical lit-
erature about children’s OCD but little study of normal
childhood ritualization, simply because the latter is not
pathological, even though it may be difficult to understand
one without the other (Evans et al. 1997). Models of OCD
do not usually cover normal episodes of obsessiveness and
ritualistic compulsion in the life-cycle although these are
probably continuous with the pathology (Mataix-Cols
et al. 2005). Very few anthropologists have considered
the striking similarities between cultural ritualized beha-
vior and individual pathology (Rappaport 1999). A
notable exception is Alan Fiske (Dulaney & Fiske 1994;
Fiske & Haslam 1997), who re-opened an issue famously
framed by Freud a long time ago (Freud 1928).
Following up on Fiske’s pioneering work, discussed in
section 8.1, as well as neuro-physiological (Szechtman &
Woody 2004) and evolutionary (Abed & de Pauw 1998)
models, we aim to provide a model of the different
domains of occurrence of ritualized behavior. We certainly
do not mean to underestimate the obvious differences, but
we do think that the common features of ritualized actions
require an explanation. We aim to provide an integrated
model that includes not only a cognitive specification of
the behavioral patterns and their elicitation conditions,
but also the neural correlates of the behaviors and of
their pathological distortion, the developmental patterns
involved, and the evolutionary background.
It might seem imprudent to make any general state-
ments about a disparate set that includes pathological
and normal manifestations, and individual as well as col-
lective rituals. Note, however, that our aim here is not to
account for all these behaviors. Our aim is to account for
the psychological salience of a particular feature they
share, namely the performance of what we call here
“Ritualized Behavior,” a precisely defined way of organiz-
ing a limited range of actions. In the following sections we
outline the diverse domains of ritualized behavior before
putting forward an integrated neural-developmental-
evolutionary model of ritualization.
2. Diverse domains of ritualization
2.1. Obsessive-compulsive disorder (OCD)
The main features of the pathology of OCD are familiar:
intrusive, bothersome thoughts about potential danger,
as well as a strong compulsion to engage in stereotyped
and repetitive activities with no rational justification. Stan-
dard criteria in the DSM-IV include (a) intrusive thoughts
that (b) cause distress and (c) are often accompanied by
ritualistic behaviors that (d) disturb normal activity and
(e) are recognized as irrational by the patient (American
Psychiatric Association 1995).
Typical obsessions include contamination and contagion
(i.e., fear of catching other people’s germs, of ingesting
contaminated substances, of passing on diseases to
others), possible harm to others (e.g., handling kitchen
utensils and wounding people), as well as social ostracism
following shameful or aggressive acts (thoughts about
assaulting others, shouting obscenities, exhibitionism,
etc.). This is often combined with “thought-action
fusion” – the assumption that having forebodings of
possible misfortunes is tantamount to bringing them
about – and an exaggerated feeling of responsibility for
others (Salkovskis et al. 2000).
Obsessions are typically accompanied by rituals. Some
patients engage in endlessly repeated sequences of
washing hands, cleaning tools or utensils (Hodgson &
Rachman 1972). Others repeatedly verify that they prop-
erly locked their door, rolled up the car window, or
turned off the gas stove (Hodgson & Rachman 1977).
Still others are engaged in constant counting activities or
need to group objects in sets of particular numbers, with
specific alignments (Radomsky et al. 2001). Although a
categorical division between “checkers,” “washers,” and
“hoarders” has become popular in descriptions of OCD
and as a descriptive clinical tool, there seems to be a
large overlap in these categories (Khanna et al. 1990). A
more accurate description would construe “contami-
nation,” “insecurity and doubt,” and “excessive precau-
tions” as dimensions of the syndrome (Mataix-Cols et al.
2005), with each patient presenting a cluster of symptoms
distributed along these dimensions (Calamari et al. 2004).
Most patients are aware that their obsessions are unrea-
sonable and their rituals pointless (patients’ insight used
to be a criterion in the DSM) but they also report that
neither is easily controlled (Eisen et al. 1999).
2.2. Children’s rituals
Most young children engage in ritualistic behaviors in a
limited range of situations and at a particular stage of
development, starting at age 2 and peaking in middle
childhood. This developmental phase is characterized by
perfectionism, preoccupation with just-right ordering of
objects, attachment to a favorite object (imbued with a
special value), concerns about dirt and cleanliness, pre-
ferred household routines, action repeated over and over
or a specific number of times, rituals for eating, awareness
of minute details of one’s home, hoarding, and bedtime
rituals. (Obviously, most children in most situations also
create disorder, at least relative to what adults expect;
insistence on “just so” performance is limited to highly
specific contexts.) The themes and the age-range are
similar among American and other cultural groups
(Zohar & Felz 2001). In many children, rituals are con-
nected to anxiety states with specific targets. Among
them is the fear of strangers, as well as the possibility of
inflicting harm to self or others, possible contamination,
attack by strangers or animals. The tendency to engage
PASCAL BOYER is the Henry Luce Professor of Individ-
ual and Collective Memory at Washington University in
St. Louis, MO, a position he has held since 2000. He
studied philosophy and anthropology in Paris-Nanterre
and Cambridge. His research so far has combined
anthropology and experimental psychology to elucidate
the evolved psychological processes that allow and
shape the acquisition of cultural information.
P
IERRE LIE
´
NARD is a post-doctoral fellow at
Washington University in St. Louis, MO, in the
Memory and Development Laboratory. He received
his Ph. D. in Anthropology from Universite
´
Libre de
Bruxelles (Brussels, Belgium). His research focuses
on the study of individual and collective ritualized
behavior, as well as the study of evolutionary aspects
of precautionary behavior.
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in rituals is correlated with anxiety or fearful traits
(Zohar & Felz 2001). Both fears and rituals typically
evolve with development, from “just so” insistence to elab-
orate rituals (Leonard et al. 1990). Younger children’s
ritualistic behaviors are related to prepotent fears such
as stranger and separation anxieties, whereas the ritualistic
behaviors of older ones are related to more specific and
contextual fears such as contamination and social hazard
(Evans et al. 1999). Some children connect their rituals
to supposed effects by magical beliefs in ritual efficacy
(Evans et al. 2002), but this is by no means necessary or
even general.
Although the facts of childhood ritualization are familiar
and impressive, there is no definitive account of the func-
tional basis of such behaviors in young children. This is
mostly because OCD pathology is seen as discontinuous
with the “normal” routines of childhood, given both the
obvious differences in frequency and emotional intensity
and the fact that only very few young ritualists become
clinically obsessive (Leonard et al. 1990). However, it
seems difficult to understand the pathology in the
absence of a proper causal model for this highly recurrent,
culturally stable part of the normal developmental process
(Evans et al. 1997).
2.3. Life-stage-relevant intrusive thoughts
Specific disturbing thoughts occur in many people at
particular phases in the lifetime, notably pregnancy,
motherhood, and fatherhood. Senseless, intrusive, unac-
ceptable ideas, thoughts, urges, and images about infants
are common among healthy parents of newborns, both
fathers and mothers (Abramowitz et al. 2003). The
content of intrusions is related to specific stages of the
life-cycle. While new fathers and post-partum mothers
report fears about harming the infant, pregnant women
report heightened fears about contamination (Abramowitz
et al. 2003). They also develop rituals of washing and
cleaning related to these intrusions. A common underlying
theme is uncertainty and doubt concerning possible harm
to the infant. Three-quarters of the new parents surveyed
by Abramowitz et al. reported persistent thoughts about
accidents, suffocation, and other possible ways of inten-
tionally harming the infant (Abramowitz et al. 2003).
The individuals feel responsible for these intrusive
thoughts. Development of specific perinatal anxieties
may be part of a “primary parental preoccupation”
complex that includes nesting behaviors, repeated check-
ing, thoughts about the infant’s perfection, and fantasies
about possible threats to its security (Leckman et al.
2004). Rodent models suggest oxytocin as a major modu-
lator of such maternal behaviors (Leckman et al. 2004).
The connection between these non-clinical context-
relevant intrusions and OCD is not just a matter of simi-
larity. The onset of OCD in women occurs during
pregnancy more than at other life-stages (Maina et al.
2000; Neziroglu et al. 1992). Note that the development
of intrusions and early rituals into OCD is quite distinct
from the evolution of post-partum depression (Williams &
Koran 1997). The former triggers very specific, highly
consistent obsessive thoughts as opposed to unfocused or
frequently shifting depressive ruminations. OCD
onset also results in an urge to act (perform specific
rituals) very different from the withdrawal from action
observed in post-partum depression (Hagen 2002).
Among OCD patients, pregnancy and postpartum result
in more severe symptoms (Labad et al. 2005). Activation
of the fronto-striatal networks as a result of infant cries
is different in new mothers and controls (Lorberbaum
et al. 2002), suggesting functional calibration of the
circuitry involved in OCD (see section 3.1.).
2.4. Cultural rituals
A great variety of social occasions are identified as “rituals”
in the anthropological literature. They range from private
ceremonies with few participants, or indeed just one
person, to large gatherings, and from single acts to long
sequences spread over months or years. The general
themes range from worship to protection to aggression.
The occasions for ritualized behaviors also vary, either
contingencies such as illness or misfortune, life-stages
like birth, initiation, and death, or recurrent occasions
such as seasonal changes. Finally, the connections
between rituals and religious concepts are crucial in
some cases (e.g., ancestor worship, Islamic prayer), or
only peripheral (e.g., anti-witchcraft divination), or just
absent (as in “secular” rituals).
How do we recognize such actions? As Roy Rappaport
argued, it seems that we (anthropologists but also lay
folk) use a conjunction of specific criteria that a model of
ritual should explain (Rappaport 1979). Here is a slightly
modified list of features he emphasized:
1. First, actions are divorced from their usual goals. In
cultural rituals, one typically washes instruments or body
parts that are already clean, one enters rooms to exit
them straightaway, one talks to interlocutors that are mani-
festly absent. Also, many rituals include actions for which
there could not possibly be any clear empirical goal, such
as passing a chicken from hand to hand in a circle, going
round a temple seven times, and so forth.
2. Second, cultural rituals are often presented as
compulsory, given a particular situation. People are told
that a particular ceremony must be performed. More
often than not, there is no explanation of why that ritual
should be performed given the circumstances. True, a
ritual often has a specific overall purpose (e.g., healing a
particular person, keeping witches at bay); but the set of
sequences that compose the ritual are not connected to
this goal in the same way as sub-actions connect to sub-
goals in ordinary behavior (Boyer 1994).
3. Third, in many cultural rituals people create an
orderly environment that is quite different from the one
of everyday interaction. People line up instead of walking,
they dance instead of moving, they wear similar clothes
or make-up, they build alignments of rocks or logs, they
create elaborate color and shape combinations, and so on.
Related to this is the recurrent concern with delimiting a
particular space (a sacred circle, a taboo territory) often
visually distinct from the other, unmarked space.
It is important to distinguish “rituals” from ritualization.
There may be lots of different reasons why particular kinds
of ceremonies are found in human cultures, why they
persist, and why they are relatively stable. We discuss
these issues elsewhere (Lienard & Boyer, forthcoming).
For instance, one may propose plausible evolutionary
scenarios for the existence of birth celebrations and of
death rituals in most cultural environments. But these
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scenarios do not explain why these social occasions all
include ritualized behavior in the precise sense intended
here.
2.5. General features of rituals
Behavior in these different domains displays obvious
similarities:
1. Compulsion. Given certain circumstances, people
feel that it would be dangerous or unsafe or improper
not to perform ritualized actions. There is an emotional
drive to perform the action, often associated with some
anxiety at the thought of not performing it (especially in
patients and children) and some relief after performance.
Naturally, this varies between domains. Anxiety precedes
ritual actions or behavior in many personal and pathologi-
cal rituals but not always in cultural rituals. Common to all
domains, though, is the important fact that compulsion
does not require any explanation. People feel that they
must perform the ritual, otherwise... [something might
happen], but they require no specific representation of
what would happen otherwise.
2. Rigidity, adherence to script. People feel that they
should perform a ritual in the precise way it was per-
formed before. They strive to achieve a performance
that matches their representation of past performances
and attach negative emotion to any deviation from that
remembered pattern. This is familiar in childhood rituals
and OCD but also in the “traditionalistic” flavor of most
cultural rituals (Bloch 1974). Deviation from the estab-
lished pattern is intuitively construed as dangerous,
although in most cases the participants have or require
no explanation of why that is the case.
3. Goal-demotion. Rituals generally include action-
sequences selected from ordinary goal-directed behavior.
But the context in which they are performed, or the
manner of performance, results in “goal-demotion,” in
performance divorced from observable goals. For
instance, people tie shoe-laces that were tied already;
they touch a specific piece of furniture without trying to
move it or use it as support; they wash hands many more
times than hygiene would require; and so on.
4. Internal repetition and redundancy. Repeated enact-
ments of the same action or gesture, as well as reiterations
of the same utterances, are typical of many rituals. A given
sequence is executed three or five or ten times. What
matters is the exact number. This makes many ritual
sequences clearly distinct from everyday action, in which
there is either no repetition of identical sequences (e.g.,
in assembling a musical instrument, one performs a
series of unique actions), or each repeated act has a
specific outcome (e.g., in weaving), or repetition is cumu-
lative (the egg-whites rise only after a long period of
whipping).
5. A restricted range of themes. Many rituals seem to
focus around such themes as: pollution and purification,
danger and protection, the possible danger of intrusion
from other people, the use of particular colors or specific
numbers, the construction of an ordered environment
(Dulaney & Fiske 1994). A ritual space or instruments
are described as “pure” or “safe” (or, on the contrary, as
the locus of concentrated “pollution”) or the point of the
ritual is to “purify” people or objects, to “cleanse” mind
or body, and so on. In collective rituals, this concern
with pollution and cleansing is so prevalent that it
has been considered a foundation of religious ritual
(Douglas 1982).
Is there a common explanation for these different
features of ritualized behavior? Here we will start from
pathology and summarize what can be safely concluded
from the clinical and neuropsychological evidence. This
supports a particular model of action ritualization which
we will also extend to developmental rituals in children
and adults, before proceeding to the distinct case of
cultural rituals.
3. Interpretations of compulsive ritualization
3.1. Neuropsychological modeling
OCD has been interpreted as a specific dysfunction of the
basal ganglia (Rapoport 1990, 1991). To understand how
this would result in the specific symptoms, the impairment
should be described in terms of the specific functions
of a cortical-striato-pallidal-thalamic circuit (CSPT). This
network includes projections from many cortical areas
(including medial and orbital frontal cortex) into the stria-
tum (caudate and putamen) and back to the cortex via
the substantia nigra and thalamus (Rauch et al. 2001;
Saxena et al. 1998). This has been confirmed by neuro-
imaging studies, as OCD is associated with increased
activity of the orbitofrontal cortex (OFC) as well as in the
striatum, thalamus, and anterior cingulate cortex (ACC)
(Saxena et al. 1998; Saxena et al. 2004). Also, the anatomy
of the caudate, putamen, and globus pallidus seems to
differ between patients and controls (see, e.g., Giedd
et al. 2000). One generally distinguishes between a
“direct” and an “indirect” pathway in the CSPT networks
(see Fig. 1). The direct pathway links (1) frontal cortices
to (2) the striatum, to (3) the globus pallidus (pars
interna) and substantia nigra (pars reticulata) to (4) thala-
mus and (5) cortex. The indirect pathway connects
(1) cortex to (2) striatum to (3a) globus pallidus (pars
externa) and subthalamic nucleus to (3b) globus pallidus
(pars interna) and substantia nigra (pars reticulata) to (4)
thalamus to (5) cortex.
The basal ganglia are involved in the formation of habits,
motor habits in particular (Rauch et al. 1997). The pattern
of projections from the cortex to the striatum suggests that
the latter may store summaries or “chunks” of motor beha-
vior. This is confirmed by involvement of the striatum in
the learning and production of habitual responses
(Graybiel 1998). Striatal networks may act as coordinators
of cortical input and orchestrators of motor habits.
What specific dysfunction would result in OCD symp-
toms? In animal models, modifying dopamine uptake in
the striatum results in stereotypic and repetitive behavior
(Canales & Graybiel 2000; Szechtman et al. 1998). So an
imbalance between various parts of the basal ganglia
system or a modification in the dynamics of cortico-striatal
pathways are probably involved in the condition. Saxena
and colleagues identify the “indirect” pathway as the
locus of impairment. In their model, the association of
globus pallidus (external) and subthalamic nucleus can
be construed as a “basal ganglia control system” that
modulates the projections to the thalamus and cortices
(Saxena et al. 1998). The indirect pathway consists of
inhibitory (GABAergic) projections from the striatum to
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the thalamus. To the extent that this pathway becomes less
tonic, it would fail to inhibit habitual motor responses and
result in unmotivated, stereotypic routines (Saxena et al.
1998).
Also important is the regulatory role played by the orbi-
tofrontal cortex (OFC) and the anterior cingulate cortex
(ACC). Early neuroimaging studies showed differential
activation of these regions in OCD patients in situations
of symptom provocation (Adler et al. 2000; Rauch et al.
1994). OFC activation makes sense given its role in the
selection, control, and inhibition of behavior as demon-
strated both by neuroimaging and by lesions of this area
(Happaney et al. 2004; Ogai et al. 2005; Schnider et al.
2005). Anterior cingulate activity is also revealing. Ablation
of the area has been used in refractory OCD cases
(Kim et al. 2003). ACC hyperactivity is not limited to situ-
ations of symptom provocation (Ursu et al. 2003). In an
event-related study of error-processing, Fitzgerald and
colleagues found increased ACC activity with error-
detection in both patients and controls, with significantly
higher increases in patients. The amount of ACC activity
also correlated with the severity of the patients’ compul-
sive symptoms (Fitzgerald et al. 2005). The anterior
cingulate can be described as an error-detection network
that activates top-down responses to situations of conflict-
ing information, for example, between expectation and
perception in errors, or between discrepant stimuli
(Van Veen & Carter 2002).
All this converges to suggest that OCD may stem from a
dysfunction of a neural system involved in the production
and inhibition of a particular set of habitual or routinized
behaviors. The etiology of the dysfunction includes prob-
able genetic factors (Campbell et al. 1999; Zohar et al.
2004) as well as infectious conditions (Giedd et al. 2000;
Henry et al. 1999), although evidence for either cause is
tentative. The compulsive nature of the actions seems to
result from a failure to inhibit strongly motivated routines
initiated in the striatum, either because striatal networks
over-respond to cortical inputs, or because their inhibitory
effect on thalamic networks is diminished, or both, leading
to ritualization. This picture is consistent with the clinical
and pharmacological evidence (Kaplan & Hollander 2003;
Zohar et al. 2004).
3.2. Cognitive models: General or specific?
Cognitive models provide a bridge from neuropsycho-
logical findings to the phenomenology of OCD symptoms.
A classical cognitive model describes the condition as
a disorder of threat-appraisal and cognitive control
(Rachman & Shafran 1998; Salkovskis 1985). Patients
produce a misguided appraisal of intrusive thoughts, exag-
gerate the threats present in the environment as well as the
extent of their own responsibility for what befalls others,
and finally fail to appreciate the measure of safety intro-
duced by normal precautions. In this model, OCD
differs from other anxiety conditions (general anxiety dis-
order, panic) only in that the eliciting stimuli are very
specific – a series of intrusive thoughts with recurrent
themes (Clark 1999).
Obsessions and compulsions might then result from a
general failure to appreciate levels of danger, to evaluate
one’s responsibility in external events, and to form an
appropriate picture of one’s situation. For instance, ritua-
lized repetition may stem from the patient’s failure to
realize that he or she has actually accomplished the
action (Pitman 1987). There is indeed evidence (though
not conclusive) for general memory problems. OCD
patients have the right intuitions in both memory for
actions and source monitoring (i.e., whether they
Figure 1 (Boyer & Lie
´
nard). A summary of some cortico-striatal pathways relevant to OCD. Continuous line for the “direct” pathway
and dotted line for “indirect” pathways (both highly simplified). SMA: Supplementary Motor Area, DLPFC: dorso-lateral prefrontal
cortex, OFC: orbito-frontal cortex, Caud: caudate nucleus, Put: Putamen, Cing.: Cingulate Cortex, NA: Nucleus Accumbens,
GP: globus pallidus (external and internal), SN(pr): substantia nigra pars reticulata, SubTh Nuc: Subthalamic nuclei.
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performed as opposed to imagined performing an action)
but they report less confidence in their own intuition
(Hermans et al. 2003).
However, there is also definite evidence for domain-
specific aspects of OCD. For instance, OCD patients are
similar to controls in their recall of neutral objects but
are markedly better at recalling dangerous items (Tolin
et al. 2001). OCD “checkers” are impaired in their recall
of own actions but less so in recall of other information
(Ecker & Engelkamp 1995). In terms of attention, modi-
fied Stroop tasks show that OCD “washers” are more
attentive to contamination words than are controls, and
OCD patients in general show more interference than
controls do from danger-related words (Foa et al. 1993).
3.3. Security-motivation
Most cognitive models of OCD are phrased in domain-
general terms. An exception is Abed and de Pauw’s evol-
utionary hypothesis about OCD as a disruption of a
specific “psychological immune system” (Abed & de
Pauw 1998). The hypothesis starts from the observation
that the prevalence of OCD would suggest the tail of a
phenotypic distribution rather than harmful mutations.
According to Abed and de Pauw, obsessional phenomena
are an exaggerated version of thought processes selected
because they lead to risk-avoidance behavior (in particular
through fear or disgust). Central to the hypothesis is the
fact that intrusive thoughts, in patients and normal individ-
uals, consist of detailed scenarios of possible danger, an
“Involuntary Risk Scenario Generating System” (Abed &
de Pauw 1998).
A similar evolutionary background motivates Szechtman
and Woody’s interpretation of the condition in terms of a
“security-motivation” system (Szechtman & Woody 2004).
The model is an attempt to integrate the diverse com-
ponents of the relevant behaviors (emotion, perception
of specific information, typical actions, inhibition or disin-
hibition of automatic routines) in a motivational system
functionally specialized in potential danger.
In contrast to general cognitive impairment models,
both Abed and de Pauw’s and Szechtman and Woody’s
models provide a parsimonious account for the specificity
of OCD intrusions.
The security system is present in all normal human
beings and monitors external signals of particular kinds
of potential danger. The neural circuitry involved in both
normal and pathological safety motivation can be broken
down in three major functional components with excit-
atory and inhibitory links. An appraisal system handles
information that matches input conditions for environ-
mental cues of potential danger. A security motivation
system handles the evaluation of these cues. A set of
various evolved security-related programs is engaged,
depending on the outcome of this motivation assessment,
with specific motor and visceral output (see Fig. 2).
As a result of engaging security-related motor-programs
(this may consist in visual inspection of one’s environment,
cleaning, ordering, etc.), the security motivation system
produces a specific experience of things being “just
right” which feeds back into the danger appraisal system.
Szechtman and Woody’s identification of the neural cor-
relates of these systems extends beyond the cortico-striatal
pathways. The appraisal of potential danger involves
perceptual and memory information and feeds into both
orbital cortex and the cortical-striatal pathways. From
there, Szechtman and Woody identify two distinct infor-
mational loops. One of them, the affect loop, includes
most of the “indirect pathway” structures, producing a
specific anxiety. In parallel, a “security-related programs”
loop, connects striatum to the globus pallidus (internal)
and ventral thalamus to elicit the performance of stored
motor routines. Finally, the normal inhibition of these
two loops is provided by brainstem structures after per-
formance of the elicited motor routines. The model
states that OCD is the result of a dysfunction in a satiety
signal, plausibly generated in brainstem structures, that
connects the performance of security related behaviors
as inhibitory feedback to a subsystem that generates and
sustains security motivation.
3.4. Outstanding questions
In our view, while current models of compulsion have
great descriptive and explanatory value, they still provide
an incomplete account of various aspects of the obsessive
and compulsive spectrum, especially if we include normal
as well as pathological manifestations of ritual dispositions.
Figure 2 (Boyer & Lie
´
nard). An interpretation of Szechtman
and Woody’s (2004) model. Rectangles correspond to distinct
systems activated, rounded boxes to behavioural results and
call-outs to aspects of the processing. Danger clues are
evaluated and action-plans selected, resulting in a “just right
feeling” that sends negative feedback to danger appraisal. This
loop is absent or impaired in patients, leading to doubts about
performance, which themselves result in repetition and rigid
action-plans.
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A more complete model should account for the following
aspects of ritualized behavior:
1. Why these specific themes? The thoughts patients
and others report are clearly not random conceptual
associations. They center on a few threats that are particu-
larly disturbing. Even this is much too broad a description.
People have intrusive thoughts about causing accidents
involving their kin, but not complete strangers; they fear
contamination more than bone fracture or inflammation;
they fear that they may have left the back door open or
the oven on, not that their car will be stolen or the
fridge will break down.
2. Why these specific actions? Compulsions seem to
focus on a narrow set of possible actions. This is clear
for contamination compulsions which result in repeated
washing and cleaning. The same applies to checking beha-
viors, limited to visual cues. Not all actions seem likely to
become compulsive.
3. Why combine the actions in that way? Many compul-
sive rituals organize action in a very specific way. For
instance, there are many negative rules in compulsions
(avoid treading on the lines on the pavement). Also,
there are specific rules about the number of iterations
(touch this chair three times) or about the order of
actions (tie the right shoe before the left one).
4. Why does ritual provide relief? Most clinicians agree
on a temporary lowering of anxiety levels after the per-
formance of rituals. The question points to one possible
explanation for the compulsive character of the behavior.
Could it be that patients intuitively reproduce behaviors
that reduce anxiety? But then, what is it about such organ-
ization of action that could reduce anxiety?
5. Why does ritual eventually strengthen obsessions?
This too is a feature often noted by clinicians (see, e.g.,
Salkovskis 1985). Although rituals provide some relief,
this is only temporary and the intrusive thoughts quickly
come back. Indeed, it would seem that the more rituals
one performs, the more focused and bothersome are the
intrusive thoughts.
4. Ritualized action: The core process
What follows is a list of the different points of the model
which will be explained in the following sections. In our
view, ritualization in young children, in normal adults at
particular life-stages, and in patients comprises a series
of processes in which specific information is acquired or
retrieved and specific behavioral plans are engaged:
1. Security-motivation systems are engaged. This may
be because of potential danger cues in the environment
(described below), information imparted by other people,
self-generated thoughts, or intrusions. In any case, these
thoughts focus on cues for potential hazards chosen in a
small set that we call the Potential Hazard Repertoire.
2. Safety motivation triggers an arousal state in which
non-action is intuitively considered dangerous (something
must be done) although there need be no clear represen-
tation of why that is the case.
2a. This state triggers a non-deliberate, non-
controlled search for action-sequences that appear
intuitively appropriate. Some cues make some
actions seem apposite although the subject generally
has no explanation for the intuition (or may only have
ex post facto rationalizations). These actions are
selected from what we call an Evolutionary Precau-
tion Repertoire.
2b. The arousal triggers a special attentional state
that focuses on low-level properties of own actions.
The action-flow is parsed in smaller units than is
usually the case.
2c. The arousal state may bias the appraisal system
in such a way that “just right” or “closure” experience
is delayed. This triggers doubts about actual or
proper performance and reiteration of action-plans.
3. Performance of the actions with attention to low-
level parsing [see 2b above] may impose a heavy load on
working memory-systems, with two consequences:
3a. The intrusive themes are temporarily pushed
away from conscious access, resulting in a short-
lived reduction in anxiety level.
3b. The intrusive themes are monitored by auto-
matic, not controlled processes, which should result
in higher salience (and renewed intrusion) after
performance.
These different steps are summarized in Figure 3. In what
follows we explain the processes engaged in more detail and
provide arguments for their presence in most domains of
ritualization. An important point to emphasize is that we
do not identify any particular component of the overall
process as being exclusively pathological. In our view,
most reactions to inferred threats engage all these processes.
Whether or not a given action triggers doubt about proper
performance, leading to rigid repetition, that is, ritualization
of these reactions, may be a matter of degree.
5. Why these particular obsessions and
compulsions?
5.1. Logic of our evolutionary approach
Intrusions and compulsions are bothersome and time-
consuming. Not only do they confer no particular adaptive
advantage, they seem to be clearly maladaptive in divert-
ing attention and memory resources from valuable goals.
However, note that OCD and other disorders of the fron-
tostriatal circuitry (Tourette’s syndrome, ADHD, and
schizophrenia) all have some genetic basis, as may be sus-
pected from their prevalence (Bradshaw & Sheppard
2000) and is tentatively confirmed by gene-loci studies
(Arnold et al. 2004; Grados et al. 2003).
To the extent that a specific kind of motivation is involved
in the pathology of ritualization (perhaps also in its normal
occurrence), it makes sense to wonder why and how
humans are endowed with this special focus on particular
kinds of hazards. In particular, are such systems the
outcome of the evolutionary history of the species? In this
case ultimate explanationswouldhelpusmakesenseof
the pathology (Nesse 1998), a strategy used in physiology
(Nesse & Williams 1996), psychiatry (Baron-Cohen 1997;
Cosmides & Tooby 1999; Stevens & Price 2000) and neu-
ropsychology (Duchaine et al. 2001; Gazzaniga & Miller
2000), and, as mentioned earlier, already outlined in some
studies of OCD (Abed & de Pauw 1998).
Providing an evolutionary model requires the following
steps: (1) Identify the relevant fitness-related problem;
(2) identify the knowledge base and computational rules
that would be minimally required to solve that problem
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in ancestral environments; and (3) provide experimental
evidence for the actual operation of a mental system that
meets this computational specification. Once this is accom-
plished, such a model may allow us to delineate possible
pathogenic scenarios, causally deeper than the vague
clusters identified in DSM-IV (Murphy & Stich 2000).
There are some indications that this approach may be
appropriate for anxiety disorders and OCD in particular.
First, negative emotions like anxiety or persistent low
mood should not be considered as dysfunctional. They
may consist in evolved warning systems whose negative
rewards steer organisms away from fitness-reducing situ-
ations (Nesse 1998). Second, the specific thoughts and
actions that compose the symptoms may be linked to evol-
utionary concerns (Leckman 2003; Mataix-Cols et al.
2005). Third, some of the conditions associated with
fronto-striatal impairment may actually result in adaptive
phenotypes (Bradshaw & Sheppard 2000).
5.2. Two types of fitness-threats
We know enough of early primate and early human living
conditions to identify broad categories of highly salient
danger in our evolutionary past: reproductive risk (e.g., for
females, mating with un-nurturing or low-fitness males; for
males, cuckoldry or choosing unhealthy females); predation
(failing to detect or deter predators); contamination from
pathogens (bacteria, viruses, toxins); resource scarcity
(e.g., failing to anticipate seasonal changes); social harm
(e.g., ostracism, but also reduced cooperation).
From an evolutionary standpoint, we should expect (1)
that such recurrent hazards, not more recent ones,
would be the target of specific emotions, and (2) that
different kinds of hazard require different decision rules.
On the first point, it is clear that specific emotions target
hazards of great evolutionary ancestry rather than more
recent ones, even though the latter may be much more
dangerous. Our danger-avoidance systems do not seem
to rely on an unprejudiced tabulation of which features
of the environment effectively predict harm or misfortune.
If this were the case, we would observe in modern
conditions many cases of anxieties, fear, or even phobic
aversions to electricity, cars, and cigarettes, which cause
vastly more deaths than do spiders and rats. But we
observe the opposite. Second, it seems that different
kinds of fitness-threats do activate different inferential
Figure 3 (Boyer & Lie
´
nard). Summary of our Potential Hazard and Precaution model. Boxes denote specific processes with
corresponding neural systems. Rounded box describes performance. Dark call-outs describe some of their typical properties. Clues
for danger must suggest hazards from the Potential Hazard Repertoire. Appraisal of the clues if modulated by anxiety, leading to
activation of plans from Evolutionary Precaution Repertoire and action-monitoring systems. At the normal end of the spectrum,
performance triggers satiety feelings with a negative feedback to danger appraisal systems. At the pathological end of the spectrum,
doubts about proper performance lead to repetition and a positive feedback to danger appraisal.
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rules. Specific principles inform the gender-specific
perception of particular mates as more or less of a waste
of reproductive potential (Buss 1989). Predator-prey inter-
action is governed by early-developed intuitions that do
not apply to other interactions (Barrett 1999). Recurrent
features of disgust reactions suggest a pathogen-minimiz-
ing system that adapts to local conditions (Fessler et al.
2003; Rozin et al. 1993) or to particular individual circum-
stances such as pregnancy (Fessler & Navarrete 2003a;
Profet 1993). Problems of resource scarcity are handled
by specific foraging strategies (Krebs & Inman 1994)
which can override explicit reasoning (Rode et al. 1999).
Finally, a host of “social intelligence” principles support
the monitoring of social interaction, from the establish-
ment of friendships and coalitions (Harcourt & de Waal
1992; Kurzban et al. 2001; Tooby & Cosmides 1996), to
dominance (Sidanius & Pratto 1999) and punishment
(Boyd & Richerson 1992; Kurzban & Leary 2001).
At this point we must introduce an important distinction
between two types of fitness-threatening situations. First,
there are cases of manifest threats, cases in which the
organism receives signals about the presence of the
source of danger: for example, a predator or enemy
attack, or seeing one’s infant in danger. Situations of this
type are handled by specialized and context-specific fear-
mechanisms in humans as in other primates (LeDoux
2003; Maren & Quirk 2004) and result in aggression,
freezing, or flight routines (Blair 2001; Payne 1998).
Second, there are inferred threats, when the potential
danger is probable given certain clues in the environment.
For instance, the strange taste of a particular dish may be
evidence of rotting; tracks may betray the recent passage
of a dangerous predator; a particular person’s attitude
may indicate that they will not cooperate. Such circum-
stances typically engage what Abed and de Pauw called
an “Involuntary Risk Scenario Generation.” Naturally,
the distinction is a rough one (many situations involve
threats for which there are direct and indirect clues). It
is also, obviously, species-specific since some situations
are a threat to some organisms but not others.
5.3. Potential danger as a specific domain
It may seem odd to hypothesize a domain-specific system
whose activation is triggered by such disparate potential
inputs as a footprint, a disgusting odor, or the fact that
one’s infant is out of sight for a moment. How specific is
the system if it can encompass such physically different
stimuli? But this objection assumes that domain-specific
inference systems are tied to a physically specified range
of stimuli, which is true for some perceptual systems
(e.g., 3D vision) but certainly not for most higher-level
functional systems. A human mind can parse linguistic
input in just the same way on the basis of auditory,
visual, or tactile information. Neuro-cognitive systems
specialized in assessing the value of potential mates use
information from conversations, from comparison of
visual information to some ideal template, from observed
interactions between the potential mate and other
people, and so forth. Indeed, it would be surprising (and
maladaptive) if a particular kind of physical input always
triggered a unique inference-system. A man is a man is a
man, but a father, a brother, an attacker, and a potential
mate should activate different mental systems.
So the autonomy or specificity of a domain-specific
system can be inferred, not from focus on a physically
specific range of cues, but from specific processing prin-
ciples, a specific kind of output, a specific learning logic,
and – in some cases – a specific pattern of impairment.
These are criteria that seem present in the case of the
Hazard-Precaution system.
There is indeed some behavioral evidence that humans
have specific inference rules for information relative to
precautions. Fiddick and colleagues have demonstrated
that when considering precautionary rules (e.g., “if you
take oranges on board you will not get scurvy”), subjects
pass logical tests for verification of rule-violation that
they fail in other contexts (Fiddick et al. 2000). This is a
replication, in another domain, of the performance on
rule-verification in the Wason selection task observed
when the rules allude to social contracts, however unfami-
liar, as opposed to other deontic domains, however fam-
iliar (Cosmides 1989; Fiddick et al. 2000). Although
these findings concern explicit judgment more than intui-
tion, they suggest that potential hazard management might
require cognitive processing that is quite different from
other inferential tasks.
5.4. The limited range of obsessions and compulsions
To explain the recurrent features of both intrusions and
compulsions, our model stipulates two kinds of data-
bases, called Potential Hazard Repertoire and Precaution
Repertoire respectively. Intrusions and compulsions have
to do with a specific, narrow range of hazards, which, in
our view, are best explained as recurrent threats to
fitness in ancestral environments.
One reason for defending this hypothesis is that the
actions combined in ritual sequences are generally
(i) species-specific and (ii) precaution-related. Ritualists
do not generally design entirely novel behavioral sequences
from scratch. Rather, they combine familiar elements of
actions (e.g., washing, cleansing, checking) into novel
sequences. This is also manifest in animal models of the
condition. The ritualistic behaviors triggered in rats
treated with quinpirole (a dopamine agonist) are species-
specific, consisting in checking with return to a home-
base, similar to those of controls, but stylized, redundant,
and time-consuming (Szechtman et al. 1998). Second,
these actions are generally relevant ones as a protection
against various kinds of fitness-threatening situations
(Rapoport & Fiske 1998). A review of the different dimen-
sions of OCD obsessions but also adult normal intrusions
and children’s anxieties should illustrate the point.
5.4.1. Contamination. Thoughts about contamination and
contagion are too specific to be interpreted as the outcome
of a general lowering of the anxiety threshold. They tend to
center on invisible agents such as toxins, viruses, and
microbes – of obvious evolutionary import. Besides,
people’s anxious thoughts about contamination focus on
modes of contact (touching with the hand, kissing,
licking, having sex, sharing food, breathing next to a par-
ticular source) that are actually used by pathogen
vectors. In patients, the compulsions associated with
these thoughts are not arbitrary either. They center on
measures such as washing and cleansing, protecting
oneself from intrusive material by staying at a distance,
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avoiding contact, suspending breathing. In ancestral
environments, before the discovery of asepsis, these
procedures would indeed constitute the only measures
to reduce or control contamination.
There is behavioral and cross-cultural evidence that a
concern with possible contamination triggers specialized
inferential circuitry in humans. For instance, Fessler and
colleagues have documented the disproportionate rep-
resentation of meat among the foods that are “good to
taboo” in many cultures. They connect this to the specific
challenges of meat consumption caused by protozoa and
other pathogens (Fessler & Navarrete 2003b). In the
same way, meat seems to be the chief target of early-
pregnancy aversions, a period of dangerous immuno-
depression (Fessler 2002). More generally, many sources
of disgust are also sources of contamination: decaying
corpses but also rotting substances, faeces, spit, and so on.
5.4.2. Symmetry and order in one’s environment. Many
children and adults are concerned with creating
an orderly environment. Children align toys in a particular
order, ritual participants need to create elaborately
ordered displays, and the same is true of many OCD
“checkers.” These behaviors are often construed, especially
in the domain of children’s rituals, as the expression of a
need for reassurance; as the urge to create a recognizable
and therefore reassuring environment.
However, this “therefore” is question-begging. What is
reassuring about a predictable environment? True, pre-
dictability implies a reduction in computational load, but
that cannot be the reason, as children and ritualists in
general devote great amounts of time and cognitive
resources creating their orderly world. So there might be
other aspects of order and symmetry that motivate cogni-
tive investment. In our view, ordered environments
combine two properties that may explain this motivation.
First, alignments and symmetry are such that they make
other agents’ intrusions clearly visible. Anecdotal (but
massive) evidence suggests that children but also various
sub-clinical obsessive personality-types get quite upset
when “intruders” such as parents or cleaners disrupt
their sequences and alignments. We speculate that the
point of the ordering may be precisely to detect such dis-
ruptions. Or rather, that the behavior may be a stored
action-plan that would have this function in other environ-
ments. This is indeed the one explanation of some animals’
“tidying up” routines as an anti-predator strategy (Curio
1993). So the creation of a non-trivial order that is not
immediately detectable by intruders may be a powerful
motivation in such compulsions. Note that childhood
rituals center on the home environment and in particular
on children’s own personal space (usually their bedroom).
Second, the specific use of symmetry and conceptual
order (alternating colors, corresponding shapes) is diag-
nostic of uniquely human dispositions to alter the environ-
ment. Bowerbirds may be among the few
exceptions – and seem to resort to similar ways of
making a display salient: pure colors, symmetry, and so
on. Indeed, people readily detect such specific altera-
tions – which has been used for millennia as a way of
advertising human presence. Cairns are improbable
pilings of rocks that no species other than human beings
would build. Broken twigs, straight paths, and color mark-
ings serve as landmarks for the same reason. What makes
this possible is the combination of sophisticated symmetry
and pattern-detection capacities in humans (Bornstein &
Krinsky 1985; Bornstein & Stiles-Davis 1984; Fisher
et al. 1981) and sophisticated tool-making capacities
(Wynn 1993). This is particularly relevant to children’s
construction of ordered environments, which may
consist of a period of systematic training in the construc-
tion of such signals of human presence.
These are bound to remain speculative as there is, to our
knowledge, no systematic research on the cognitive and
emotional processes involved in ordered displays, particu-
larly in children’s strong motivation to produce such
environments.
5.4.3. Social offence. Some of the intrusive thoughts of
obsessive people center on possible acts that would
offend or harm other people, resulting in social exclusion.
These fears also represent, in our view, a domain of evol-
utionary hazard. Given human dependence on conspeci-
fics for all aspects of survival, it is not surprising to find
that possible social strife is seen as extremely dangerous.
Life in complex societies makes this dependence diffuse
and impersonal. By contrast, in ancestral environments
people depended on known members of the group.
Conflict in such groups threatens each member’s access
to resources, cooperation, and information (Tooby &
DeVore 1987). In this domain too, it seems that the pre-
cautionary measures taken by obsessives are in fact
rather appropriate. For instance, one of the features of
OCD patients (especially checkers) is a tendency to
monitor actions, in particular the minutiae of one’s own
behavior, well beyond the “normal” limits. Another
common feature is that people choose to avoid social
contact lest they insult or assault others, which again is
intuitively appropriate as a precautionary device.
5.4.4. Harm to offspring. Intrusive thoughts reported by
adults often focus on possible harm to one’s own offspring,
accompanied by fears of handling tools and utensils in a
dangerous way, smothering or dropping the infant, as
well as forgetting about the baby and losing it (particularly
in stores and other public places). Again, the danger is one
of obvious evolutionary significance, as tools and weapons
are part of our ancestral past. Also, shifting attention away
from one’s infant is risky but unavoidable in humans who
need to attend to such tasks as foraging or processing food.
Again, the compulsive precautions (hyper vigilance,
neglect towards other people and social interactions,
etc.) would seem appropriate given these hazards.
5.5. The Precaution System associates domain-specific
repertoires
Specific reactions to inferred threats suggest a functional
system that we called the Precaution System, whose
specific input consists in inferences to non-manifest
threat and whose output is selective activation of particular
precautions. At both ends of its operation, the postulated
system is highly specific. The Precaution System does
not respond to all or most actually significant signals of
potential danger, but to a limited repertoire of cues. As
we said above, humans seem to infer fitness threats, with
a specific anxiogenic response, from wounds or rotting
carcasses, but not from tobacco smoke or electricity.
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The range of action-plans activated is also restricted to a
few possible precautions (washing, avoiding contact, etc.)
that may or may not be most appropriate given changing
circumstances. Note that this model does not account
for some sub-varieties of OCD symptomatology. Hoard-
ing, for instance, does not seem to result in ritualized
behavior in the precise sense described here. This may
be because the underlying processes are different from
other OCD dimensions, as is suggested by neuroimaging
studies (Calamari et al. 2004; Saxena et al. 2004). In our
model, the specificity of cues and responses maps a set
of highly recurrent threats in human evolutionary history.
6. Why the complicated action?
6.1. Ordinary action-parsing
The ritualization process imposes particular constraints on
the performance and sequencing of action. This is why the
features of ritual should be considered in the context of
action representation in general. Human beings attend
to each other’s behavior and react to it, which means
that they must “parse” other people’s and their own beha-
vior in meaningful units (Newtson 1973). The experimen-
tal study of such parsing mechanisms provides a
background against which we can understand specific fea-
tures of ritual.
People identify actions as belonging to particular cat-
egories (e.g., putting on one’s socks) but also as part of
larger sequences (putting on one’s socks as part of
getting dressed). This “partonomic” structure is general
to action sequences in normal contexts. Small units are
parts of larger units and the boundaries between large
units tend to coincide with a boundary at a lower level.
Zacks and colleagues distinguish between three levels of
representation: that of simple gestures (sequences of a
few seconds), that of behavioral episodes (an order of
longer magnitude, actions like “getting dressed”), and
that of a script (series that can span a much longer time,
e.g., “eating out,” “giving a talk”) (Zacks & Tversky 2001;
Zacks et al. 2001b).
In the absence of specific instructions to the contrary,
people spontaneously describe and recall behavior in
terms of middle-level behavioral units (Zacks & Tversky
2001; Zacks et al. 2001b), that could be called a “basic
level” for event-taxonomies (Rifkin 1985). Indeed, people
can generate far more categories of events at that
middle-level than either super- or subordinates (Morris
& Murphy 1990). Mid-level breakpoints also correspond
to specific neural activity (Speer et al. 2003; Zacks et al.
2001a). It is certainly not a coincidence that this is also
the level of description at which people typically ascribe
goals to behavior. While gestures do not readily reveal
intention, and scenes include many different intentions,
behavioral episodes typically constitute the realization of
a particular goal. Action-parsing develops early in infants
and seems to focus on the intentional unit level from that
early stage (Baldwin & Baird 1999; Baldwin et al. 2001).
6.2. Goal-demotion in ritualized action
These studies converge to suggest that spontaneous
parsing focuses on middle-level action-units connected
to specific goals. It is very difficult for normal humans
not to parse action at that level. Indeed, an excessive
focus on a low-level, gestural description of behavior,
with the attendant imprecision about goals, is character-
istic of frontal lobe or schizophrenic patients (Janata &
Grafton 2003; Zalla et al. 2003).
Now this focus on low-level gesture analysis of the
action-flow is precisely what happens in cultural and indi-
vidual rituals. People’s attention is typically drawn to the
details of performance, the particular direction of a
gesture, the specific number of times an action should
be performed, and so on. Conversely, the description of
ritual action in terms of goals is either not available or in
any case irrelevant.
This is what we call “goal-demotion.” Although there
may be a goal for the overall ritual script, there are no
obvious sub-goals for its components. In typical patients’
rituals or in developmental rituals, there may be an explicit
goal. For instance, producing a particular alignment of
twigs in a particular order is supposed to ward off intruders;
or a sequence of familiar actions, for example, tying one’s
shoes in a very specific way, will prevent accidents. But
the contribution of each part of the script is not connected
to particular sub-goals. For some ritual actions it is imposs-
ible for the actor to imagine what contribution they would
make as they reverse the results achieved through previous
actions (e.g., piling up objects and carefully putting them
back in a line before piling them up again). More generally,
the actions are considered an indispensable part of the
script although the subject has no representation of why
he or she should be included in it. This contrasts with the
standard parsing of action-flow, where the units identified
at all levels of partonomic division correspond to specific
goals. Indeed, in a typical example of routinized efficient
practice, that of blacksmithing techniques, the correspon-
dance between action-units and goals serves to mobilize
different units of knowledge as they become relevant to
the sub-task at hand (Keller & Keller 1996). This is empha-
tically not the case in ritualized behavior, the performance
of which seems to be a “tunnel” in which each action only
points to the following one in the prescribed sequence
(Bloch 1974).
6.3. Swamping of working memory
There is very little study of the attentional effects of the
focus on low-level features of action, combined with
high control and hypersensitivity to possible mistakes,
during performance of personal rituals. Our model
suggests a specific, temporary effect on working memory
which would explain some effects of rituals. Working
memory is a specific memory system that holds infor-
mation for a short time and allows updates and transform-
ations of that information (Baddeley 2000). In typical
working memory tasks subjects are asked to repeat a
sequence of letters in the right order, repeat in inverse
order, repeat the sequence formed by letters while ignor-
ing digits provided in between, or specify which was the
third letter before last in a series that ends unexpectedly.
In all such tasks, the subject must consider a certain set
of information units or chunks at the same time in order
to perform the required operations (Baddeley 2000).
In our view, one of the effects of prescribed, rigidly
compulsory action-sequences is a momentary overloading
or “swamping” of working memory, especially if the action
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sequences are represented at the fine-grain parsing level.
This is very much what happens to some patients whose
spontaneous action-parsing remains at this same low
level of description. As Zalla puts it in her description of
frontal lobe patients, “the weakening of the causal connec-
tions between the component actions leads to the
decomposition and the fragmentation of the action rep-
resentation. [...] The increased amount of fragmented
information rapidly overloads subjects’ working memory
capacity” (Zalla et al. 2004). A similar point can be made
about fragmentation of action in OCD compulsions
(Ursu et al. 2003).
Many ritual prescriptions resemble the tasks designed
by cognitive psychologists in the study of working
memory. They require focused attention on a set of differ-
ent stimuli and their arrangement. For instance, a require-
ment to turn round a ritual pole three times clockwise
without ever looking down imposes executive control of
two tasks at the same time. Also, the frequent combination
of a positive prescription (“do x...”) and a negative one
(“...while avoiding doing y”) would seem to engage
working memory and executive control in a way that is
not usually present in everyday action flow.
6.4. Core ritualization is the opposite of routinization
In the model proposed here, ritualized acts are very differ-
ent from other routines. However often an individual may
perform a ritualized action, it does not seem to become
automatic. On the contrary, it remains constrained by
high-level cognitive control. Ritualized actions as
described here require high cognitive control because
the rules often apply to familiar actions (e.g., walking,
talking, preparing food) and turn them into more difficult
tasks (e.g., walking without treading on the line). This
clashes with a commonsense notion that rituals only
include actions that one performs “routinely” or “without
thinking.” Indeed, it is essential to our model that the com-
ponent of rituals that we called Ritualized Behavior cannot
be automatic.
7. Implications of the model: Individual ritual
7.1. Intrusions as context-sensitive adaptive
algorithms
A surprising conclusion from the very few systematic
studies of intrusions and mild compulsions in the normal
population is that thoughts about potential dangers (con-
tamination, social harm) and some compulsive reactions
are not confined to the clinical population. Most normal
people seem to experience the same kind of intrusive
thoughts as patients do, and to some degree generate
the same ritualized action-plans to avoid such dangers
(Abramowitz et al. 2003; Rachman & de Silva 1978). The
crucial difference, then, is not in the contents of the
thoughts but in their appraisal (Salkovskis 1985).
The evidence available is insufficient to address the
fundamental questions of the distribution, themes, intensity,
and effects of intrusions in the normal population. Our
model implies that intrusions are generally not dysfunc-
tional. They are the outcome of systems geared to protecting
the organism against potential dangers by over-interpreting
specific inputs, which would suggest this prediction:
[P1] The position of an individual along fitness-related life-cycle
dimensions (young vs. old, male vs. female, nulliparous vs.
multiparous, high vs. low status) should predict the frequency,
intensity and contents of intrusive thoughts.
So far, we only know that contagion and risk intrusions
become highly salient during the perinatal period
(Abramowitz et al. 2003; Leckman et al. 2004). This may
also be true of other stages in the life-cycle, such as
puberty, menarche, and the death of relatives. There is
simply no general, population-sample study of thought-
intrusions and their correlates. Sampling bias is particu-
larly likely in this domain. Perinatal intrusions get
noticed only because pregnancy is a period of higher
medical monitoring.
7.2. Spontaneous optimization and relief
Why the strange rules and prescriptions in compulsive
action? Also, why should such performances induce tem-
porary relief? Many patients explicitly associate their
rituals with specific obsessions, stating that performing
the ritual is one way of inhibiting or repressing the
unwanted thoughts (Salkovskis 1985). Clinicians’ obser-
vations and patients’ reports converge in suggesting that
the relief from unbearable anxiety, though temporary, is
palpable. But there is nothing in current cognitive
models to explain the fact.
In our view these two questions are related, and the
common answer lies in the effects of ritualization on cog-
nitive control and working memory. We suggested earlier
that the performance of rituals, accompanied by numer-
ous, specific, attention-demanding prescriptions, has the
effect of “swamping” working memory. We propose that
such rituals constitute spontaneous and moderately effi-
cient forms of thought-suppression. The difficulties of
thought suppression in everyday life (trying not to recall
unpleasant experiences or not to mull over possible
future misfortunes) are familiar to everyone. Dan
Wegner and colleagues have studied the phenomenon in
controlled environments and demonstrated the complex
control processes at work in such attempts (Wegner &
Erskine 2003; Wegner & Schneider 2003). One interesting
feature of these experimental studies is that only a few
techniques are available to effectively “push away”
unwanted thoughts. They include focusing on emotional
information of greater intensity than the target thoughts,
or focusing attention on intrinsically difficult tasks like
mathematical problems. These are difficult precisely
because they recruit working memory to a greater extent
than most everyday tasks and cannot be accomplished
automatically.
Obviously, compulsive rituals are in many ways different
from the phenomena observed in such studies. First,
Wegner’s subjects generally have no intrinsic motivation
to avoid the suppressed thoughts, other than compliance
with the experimenter’s instructions. By contrast, OCD
patients are strongly motivated. Second, the intrusions in
patients are far stronger (more difficult to push away
from consciousness) than a simple neutral theme
suggested by an experimenter. Third, patients have a
history of thought-intrusion and thought-avoidance,
whereas experimental subjects are genuine beginners in
the domain.
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Notwithstanding these differences, we think the studies
on thought-suppression are important to suggest a possible
mechanism for the elaboration and rigidity of ritual pre-
scriptions. In our view, patients with complicated compul-
sions have spontaneously attained an optimal point in the
kind of activity that is so demanding in cognitive control
that intrusive thoughts can be, at least for a while,
pushed away from consciousness.
This “trick” exploits certain features of the action-
parsing systems reviewed (see sect. 6.1). Given that
action-parsing processes are engaged when any behavior
is witnessed or produced, there are not many tricks that
could force attention to focus on the low-level description
of action. Among these features is repetition, which results
in goal-demotion. Another such gimmick, obviously, is to
borrow a sequence from ordinary scripts and perform it
in a context that makes goal-ascription impossible: for
example, wash objects without using water, pretend to
trace an imaginary line, and so on. What results from
these “tricks” is what we called “goal-demotion” above.
Actions are represented without attaching a goal to each
behavioral unit, as would be the case in non-ritual
contexts.
This has several implications for the organization of
compulsive rituals:
[P2] Compulsive actions should be such that they mobilize
working memory and require high degree of cognitive control.
We have suggested that this is precisely what complicated
prescriptions achieve, in particular when they result in
control of usually automatic actions, such as choosing
which shoe to tie first, or whether to push the doorbell
button with this or that finger.
[P3] Compulsive rituals may be the outcome of a trial-and-
error process.
This means that patients more or less deliberately (usually
not) try various behaviors with various prescriptive rules
until they reach an optimum, that is, the maximal occu-
pation of working memory that is compatible with the
intrinsic limits of memory itself. This would carry
another consequence:
[P4] The symptoms should become unstable if the actions
become routinized.
Working memory is effectively swamped when usually
automatic actions are submitted to cognitive control. But
even demanding tasks (e.g., tying one’s shoes in a particu-
lar order that changes with the time of the day) might
become partly automatic with time. One would predict
that this would result in diminished efficacy and the spon-
taneous search for different prescriptions, or for more
complex sequences. Naturally, this dynamic model does
not imply that patients are at any point aware of the
effect of prescriptive rules on memory. They may simply
come to associate slightly more controlled action to slightly
diminished intrusion, which would be enough gradually to
lead to the baroque complications of individual rituals. We
do not have much comparative clinical evidence concern-
ing the particular contents of obsessive-compulsive rituals,
that is, the number of actions, their precise description,
their prescribed order, and so on, as opposed to general
descriptions such as “washing” or “checking.” Nor do we
have much in terms of longitudinal studies of ritual elabor-
ation or progression; which is why these remain speculat-
ive predictions from the model.
7.3. Ironic outcomes
Studying normal subjects instructed not to think about a
particular item, Wegner showed that thought suppression
typically results in a “rebound” – in higher salience of the
unwanted thoughts (Wegner & Schneider 2003). This, in
Wegner’s model, is caused by the combination of two dis-
tinct processes engaged in thought suppression. While an
explicit process directs and monitors the suppression,
implicit processes are engaged that detect material associ-
ated with the target item (Wegner & Erskine 2003). Here
again, we do not wish to read too much in the parallel
between an experimental paradigm and a long-lasting
behavior pattern. However, an ironic outcome would
seem to follow from the working-memory swamping
scenario:
[P5] The precise intrusions that rituals can tone down should
become more frequent or more difficult to resist as rituals
are frequently practiced.
Although it has not been studied in precise quantitative
terms, this ironic rebound does seem characteristic of
compulsive rituals (Rachman & de Silva 1978). The
patients who perform more rituals are typically more
anxious, and also more bothered by their intrusive
thoughts. In other words, the long-term effects of ritual
performance are the opposite of its short-term results.
Indeed, this may be why an effective cognitive and beha-
vioral therapy for OCD, in particular exposure and reac-
tion prevention (ERP), requires that the patient evoke
the dangerous thoughts but restrain the compulsive
response (Rachman et al. 1971).
7.4. Developmental calibration
Our model implies specific claims about the Hazard-
Precaution system in children, suggesting that early
childhood is a period of calibration of the system. Many
cognitive systems require calibration, that is, a change in
parameters as a function of specific information picked
up in the child’s environment (Bjorklund & Pellegrini
2002). A salient example is the development of food-pre-
ferences in young children, with a period of unlimited tol-
erance followed by “parameter-setting” when young
children reject anything that does not taste familiar
(Birch 1990). Another domain would be predator-prey
relations, in which common assumptions are gradually
refined in view of local circumstances (Barrett 2005).
We can make a similar point about the Potential Hazard
Repertoire. As we said, the system should handle indirect
clues and produce inferences about the potential presence
of dangerous substances, predators, and conspecifics. But
it immediately appears that the number of possible clues is
multiplied by the fact that (a) any one of these dangerous
situations could be detected using a large number of poss-
ible clues and (b) the situations themselves must have
changed a great deal, and changed frequently, during
human evolution. Indeed, modern humans have adapted
to variable conditions of subsistence in primary forests,
grasslands, and dry savannas. They also had to adapt to
seasonal changes. Most important, cultural evolution led
to rapid cultural change, or “life in the fast lane” (Boyd
& Richerson 1995). Ecological and cultural change
means that old predators are gone but new ones are
present; that noxious substances are not found in
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the same plants or animals; and that social interaction is
handled in significantly different ways.
In this way the security system is a learning system, that
appears in infants as a disposition to pick up particular
kinds of locally relevant information from the natural
and social environment, and changes its parameters as a
function of that information. This would explain not just
why children perform ritualistic behaviors, but also why
the phenomenon appears and subsides at particular
stages of development and why its typical manifestations
evolve from prepotent fears for which there is clear prepa-
redness, to more complex inferred threats like social harm.
The system is designed to address a specific question: How
to create a secure environment and to provide a series of
contextually relevant solutions like washing, cleaning,
checking, or modifying one’s interaction with other
agents? This implies particular directions for development
in the kinds of thoughts and compulsions found in child-
hood. If the system is in calibration during that period,
we should observe the following:
[P6] Anxiogenic thoughts should become gradually more
specific with development.
[P7] Compulsive reaction should become more specific with
development.
In terms of anxiety, a fear of vaguely defined predators
animals should become a fear of particular animals, a fear
of strangers should become a fear of particular strangers,
and so forth, as the system picks up information from
the environment. This applies to compulsions, too. At an
early stage, all recipes should be equiprobable. At a later
stage, children should acquire locally relevant associations
between a particular potential danger and a particular
recipe. This also predicts differences in the rituals of
older children from different groups. To the extent that
different cultural groups live in different conditions, differ-
ent kinds of dangers would be relevant and different clues
significant:
[P8] Fears and compulsions should become more culturally
specific as children get older.
We already have some fragmentary evidence that devel-
opmental trends in children’s fears support these predic-
tions. Fantasies and intrusive thoughts change with
development, as mentioned earlier (Evans et al. 1999;
Leonard et al. 1990).
7.5. Cultural similarities and differences in
pathological ritual
Our model assumes that there is a Precaution system
focused on certain kinds of potential danger. We also
suggested that this system undergoes calibration during
childhood, given that clues about potential danger
change with changing environments. This would imply
specific predictions about cross-cultural variations in the
condition:
[P9] Anxieties and fears that result in compulsion belong to the
narrow range of ancestral potential dangers: contamination,
intrusion, social offence, and resource-depletion.
[P10] We should observe important cultural differences in the
relative prevalence of symptom clusters (or “subtypes”).
There is very scant comparative anthropological
evidence for anxieties or fears, although it seems to
suggest something of this kind. In industrialized countries,
the notion of electricity and cars as massive killers is
virtually absent from the repertoire of phobic and obses-
sive patients. Also, the few studies of OCD patients in
non-Western environments report the familiar obsessive
themes of social offence, contagion, and potential danger
(Abdel-Khalek & Lester 1998; Arrindell et al. 2002;
Barker-Collo 2003; Bertschy & Ahyi 1991; Sasson et al.
1997) and the prevalence of OCD as a general category
is the same in different places (Weissman et al. 1994).
Cultural differences too are suggestive, although there
are to date very few (reliable) comparative studies of the
condition and most of them only bear on clinical popu-
lations (so we have no evidence of what intrusive thoughts
are common or exceptional in the population at large). For
instance, a study from Bali documents a culture-specific
tweaking of the general OCD themes. The patient needs
to identify all passers-by in terms of genealogy and
status, and reports obsessions about spirits and witches
(Lemelson 2003). Both are culturally specific variants of
the social harm and social exposure obsessions, as hierar-
chy and status are fundamental to social interaction in
Balinese society and social strife is expressed through
witchcraft accusations (Barth, 1993). In Muslim countries,
by contrast, many patients report concerns about pollution
and contamination strongly influenced by religious pre-
scriptions on hygiene and purity of thought (Al-Issa
2000; Mahgoub & Abdel-Hafeiz 1991; Okasha et al.
1994). A sample of Bahrain patients showed that the fear
of blasphemy was prevalent (about 40% of cases), which
may be a local expression of the fear of social harm and
potential exclusion (Shooka et al. 1998).
This would suggest that an important calibrating factor is
the range of cultural messages emphasizing potential
danger. In particular, further epidemiological studies of
the various dimensions of OCD (contagion, social offence,
checking) may be correlated to the intensity of precaution-
ary messages available in the environment of development.
While Islam includes many descriptions of possibly impure
actions or thoughts, Western children are bombarded with
insistent warnings about invisible germs. Whether this
results in significantly different normal and pathological
intrusions is simply not documented yet.
8. Implications of the model: Cultural ritual as
derivative
So far, we have not mentioned one of the most salient and
socially important manifestations of ritualized behaviors,
namely, collective, culturally sanctioned rituals. We con-
sider that the model presented so far can help us under-
stand why rituals are widespread the world over and why
they are compelling – an argument summarized here
and presented elsewhere in more ethnographic detail
(Lie
´
nard & Boyer 2006).
8.1. A capacity for ritual?
We start from the work of Fiske and colleagues. Compar-
ing hundreds of ritual sequences with clinical descriptions
of OCD cases, they showed that the same themes recur
over and over again in both domains (Dulaney & Fiske
1994; Fiske & Haslam 1997). OCD-typical features that
also enter into rituals include specific (lucky or unlucky)
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numbers, use of special colors, repetition of actions,
measures to prevent harm, ordering and symmetry, sty-
lized verbal expressions, washing, concern with contagion,
and so forth (Fiske & Haslam 1997).
Fiske and colleagues speculate that there may be a
human capacity to perform cultural rituals, that is dis-
torted or hyperactive in pathological individual ritual
(Fiske & Haslam 1997). In Fiske’s model, rituals are
used to channel individual anxiogenic thoughts and make
them bearable by providing a broader cultural context in
which they can be shared and make better sense. Fiske
and Haslam did not pursue the psychological and cultural
implications of this hypothesis. It would provide a simple
and elegant way of explaining the similarities in themes
and actions between pathological and cultural ritual.
Moreover, it would do so by connecting both to evolved,
species-specific anxiogenic situations.
However, we consider that cultural rituals may be better
explained in a different way, as partly parasitic on the
Hazard-detection and Precaution systems described
above. Our main reason for preferring this account is
that it is more parsimonious. There is no empirical evi-
dence that humans do have a specific capacity for ritual.
There are no evolutionary grounds to consider that such
a specific capacity would be adaptive (see our discussion
of rituals as possible adaptation in section 9.1.) So this is
a costly hypothesis. By contrast, we have seen that there
is solid evidence for systems specialized in responses to
potential hazard. So if the disposition to perform cultural
rituals is a by-product of these systems, we do not need
to posit additional mechanisms.
8.2. The cultural selection background
The first assumption in our treatment is that cultural
rituals, like other forms of cultural behaviors, should be
treated as the outcome of cultural selection (Boyd &
Richerson 1985; Durham 1991; Sperber 1994). Represen-
tations that we call “cultural” occur with roughly the same
content in other minds among people of a particular
group. Indefinitely many factors (local or universal,
psychological as well as physical) can in principle contrib-
ute to the spread of a particular mental representation.
One type of factor of great interest to us is the set of
general human dispositions that make certain represen-
tations, once they are expressed or conveyed by some
people, particularly attention-grabbing or memorable or
compelling, leading to their cultural transmission
(Sperber 1985).
We observe that people seem compelled to perform
particular ceremonies at particular junctures, and also
that they seem compelled to perform them in (what they
judge to be) the prescribed way. This is what we need to
explain. Now, one way to explain this would be to posit
that there must be a particular urge to perform such cer-
emonies, or that they may fulfill particular needs of the
human mind or of human groups. However, there may
be another kind of explanation, based on the fact that
people who receive information about particular perform-
ances already have sets of mental systems designed to
respond to particular classes of stimuli. The question
becomes: What mental systems would be activated, such
that performing this ceremony in these circumstances
would seem compelling?
8.3. Cultural information, mimicry, and
cognitive capture
Cognitive systems can be functionally described in terms
of their particular input format, their operating principles,
and their output. The input formats of cognitive systems
are, in some cases, well known. For instance, the auditory
stream provides information about pitch and location,
which is then routed to different systems (Kaas et al.
1999; Romanski et al. 1999). The pitch information is
divided into linguistic input and non-linguistic input,
transmitted to different parts of the auditory cortex
(Liegeois-Chauvel et al. 1999). At each step, the transfer
from one system to the other depends on the signals’
format. This extends to higher cognitive systems.
The range of stimuli or internally generated information
that meets the input format of a system is its domain. Now
it is important to distinguish between an evolutionary or
proper domain of stimuli and an actual domain (Sperber
1996). The proper domain includes those objects or situ-
ations that played a causal role in giving the particular
system a selective advantage. The actual domain includes
all objects or situations that trigger activation of the
system. In most evolved cognitive systems, the actual
domain is larger than the proper domain, giving rise to
false alarms. The frog snaps at any small objects whizzing
by in its visual field, not just to actual edible insects.
Anysystemofthiskindisvulnerabletocapture and
mimicry. The terms describe situations in which the
system reacts to an input that matches its input format, is
part of its actual domain, yet is not among the classes of
stimuli that the system was designed to process, its proper
domain. We reserve the term “mimicry” for the situations
in which a particular behavior or physical trait in an organ-
ism gains adaptive value by entering the actual domain of
another organism’s cognitive system. This is what happens
in familiar cases, like that of Viceroy butterflies adopting
the genuine poison-warning garb of Monarchs without
having to manufacture the poison.
A different situation is what we call “cognitive capture.”
Consider a familiar example. Most visual art in humans
(from tattooing to painting to architecture) seems strongly
biased towards vertically symmetrical displays, while other
symmetries are less salient. Vertical symmetry detection
capacity appears in infancy (Bornstein & Krinsky 1985;
Fisher et al. 1981), influences pattern recognition in child-
hood (Bornstein & Stiles-Davis 1984; Mendelson & Lee
1981), and has evolved for purposes other than the appreci-
ation of aesthetic displays, most probably for detecting
facing predators and healthy mates (Thornhill 1998).
Music too is a good example, as it “hijacks” certain parts
of the auditory cortex and provides auditory super-stimuli
(Jerison 2000). Narratives about imagined persons can be,
as we say, “captivating” because they capture our capacities
for mind-reading and the explanation of behavior.
This is not mimicry since in the cases mentioned here
the organism’s Type I error does not benefit another
organism. The important point about cognitive capture is
that a great deal of human culture is acquired and trans-
mitted because of this inevitable propensity of cognitive
systems to “fire” beyond their proper functional range.
Most items of “culture” in the sense of group-specific
sets of norms and concepts depend for their transmission
on cognitive capture of this kind (Sperber 1996).
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8.4. Core ritualization in cultural rituals
To understand the cognitive effects of collective rituals, we
must describe the kinds of information available to the
participants. At first sight, it would seem that most
people who participate in most rituals do not have much
information at all. People do not generally hold a
“theory” of their own rituals – this is what makes ethno-
graphy indispensable and difficult.
However, this is not to say that people participate in a
ritual on the basis of mere imitation, peering at their cul-
tural elders and simply performing similar gestures. This
would be implausible, given that very little human cultural
transmission actually involves such mindless imitation
(Sperber 2000). In this particular case, some behavior acti-
vates some mental templates in the mind of observers, and
triggers non-random inferences about what is accom-
plished by the behavior. This, we contend, may be suffi-
cient to explain the cultural success of Ritualized Behavior.
To make comparisons simpler, we follow in our descrip-
tion the outline of action ritualization processes described
earlier. The individual reaction to a particular cultural
ritual can be functionally described as consisting in the fol-
lowing elements:
1. People receive specific information about the ritual:
a. They are told that a ritual should be performed
and are led to infer that non-performance is a
dangerous option. For instance, one is told that
because of a particular event (someone’s illness, a
death or a birth, the change of seasons, a war with
another group, possible damnation), it is necessary
to go through a particular ritual sequence.
b. People also receive information and produce
inferences about the kind of danger against which
the ritual is supposed to protect the group, for
example, “pollution” by invisible substances, attacks
by invisible predators like witches or spirits, threat
of disease, possible famine, social strife, and so on.
These themes substantially overlap with the
Potential Hazard Repertoire.
2. This triggers a (dampened) activation of Hazard-
Precaution system.
3. People are instructed to participate in the ritual in
particular ways. That is, people are generally not
allowed to just add to their ritual whatever action
they think fit. They are enjoined, more or less expli-
citly, to follow a particular script. Information about
the script has the following properties:
a. Action descriptions include themes that mimic
some of the typical outputs of the Hazard-Precaution
system: actions such as cleansing, washing, checking.
b. Descriptions of prior conditions, particular
taboos, substances to avoid, et cetera, reinforce
activation of security motivation system.
c. There is great emphasis on the details of each
action, inducing low-level parsing of the action flow
during performance, especially because of negative
prescriptions.
d. Description induces goal-demotion, by insisting
on repetition, redundancy, apparently pointless
acts, and so forth.
4. Performance enacted in these conditions temporarily
swamps working memory because of the attentional
demands of the tasks.
5. Performance ironically strengthens the salience of
particular themes associated with gestures or situations
to avoid during ritual.
These various elements and their putative causal
relations are outlined in Figure 4. In the next sections
we present some evidence for these various claims and
for the psychological and cultural effects of the processes.
8.5. Cognitive capture in cultural rituals
Our model suggests that ritualized actions are culturally
successful to the extent that they activate information-
processing and motivation systems made manifest in
other domains of ritualization. In this sense, cultural
rituals result in cognitive capture of the systems described
so far, and this is why they can seem attention-demanding
and compelling to participants.
Many features of collective rituals activate the Hazard-
Precaution system by including cues for potential
dangers of the Evolutionary Potential Hazard Repertoire.
First, occasions for ritual often allude to clues of possible
danger that overlap with the Potential Hazard Repertoire:
for example, threats to fitness such as famine or illness,
invisible germs or miasma, dangerous invisible pollution
present in newborn infants, dead bodies and menstruating
women (Bloch & Parry 1982; Metcalf & Huntington
1991). Second, details of prescribed performance also
include many security-related motifs. As we said pre-
viously, many collective rituals include such operations
as washing and cleaning, checking and re-checking that a
particular state of affairs really obtains, as well as creating
a symmetrical or otherwise orderly environment
(Dulaney & Fiske 1994; Fiske & Haslam 1997), so we
will not comment on this any further.
In our model, precaution systems are activated to the
extent that particular themes (e.g., “this village must be
purified”) and prescribed actions (e.g., “wash hands
three times in this particular river”) trigger activation of
evolved Precaution systems. This, however, does not
entail that the ritual as a whole should be explicitly and
exclusively about these themes. Indeed, there are many
ceremonies in which prescribed behavior is only weakly
related to these themes, while other themes (e.g., procrea-
tion, social exchange, hierarchy) are at the forefront of
people’s attention. Our claim is only that the ritualization
itself is derived from the operation of Precaution and
action-parsing systems.
8.6. Ceremonies, ritualized action, and routinization
This model, in our view, provides at least elements towards
an explanation of why ceremonies that include ritualized
actions are found in most human groups and are generally
stable within traditions. The model also has some impli-
cations that make it diverge from received anthropological
usage and common intuitions about ritual.
Ritualized actions are not “rituals.” Ritualized actions as
described here are only a subset of what people actually do
in what are called “rituals.” For instance, a ceremony may
include a typical example of what we described earlier,
such as, a prescription to turn around a cow three times
clockwise while avoiding to stare above the horizon and
making sure to touch the cow with one’s thumb only.
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But the circumambulation of the cow may be an element
of a larger ceremony that also includes singing, dancing,
feasting, and all sorts of other behaviors that are not pre-
cisely scripted in the sense described here. In other
words, ritualized behaviors are certainly not the whole of
“rituals.”
Ritualization is not routinization. The model has the
slightly counter-intuitive implication, that ritualized
action is described as quite different from routinized beha-
vior, indeed as its opposite. In most ceremonies we expect
to find an alternation between phases of ritualized action
(high control, attentional focus, explicit emphasis on
proper performance) and routinized action (possible auto-
maticity, low attentional demands, lesser emphasis on
proper performance).
Cultural ritual is not individual ritual writ large.We
said that cultural ritualized actions are “derivative” and it
is important to stress that they are a by-product of the Pre-
caution systems and the action-parsing systems, not of
individual ritualized behavior. Given the similarities
between individual and cultural forms of ritual, it is of
course tempting to take one as a scaled version of the
other, as Freud suggested (Freud 1928). But this is
clearly misguided. First, to maintain the parallel, cultural
rituals would need to be behaviors that social groups
initiate because they perceive certain potential dangers.
But groups as a whole do not literally behave or perceive,
only their members do. Also, cultural rituals differ from
individual ones in the way the information about compel-
ling action is acquired – from other agents and from
personal intuition, respectively. Most importantly, what
compels performance is entirely different in the two situ-
ations. While individual ritualists (especially patients) may
feel great anxiety at the prospect of not going through the
ritual sequence, participants in a cultural ritual are likely to
participate (among other reasons) to the extent that the
particular sequence meets a minimal threshold of rel-
evance. The idea of “scaling” would also predict all sorts
of interesting phenomena that are simply not observed;
for example, that people who become more religious
would tend to become more obsessive, or that OCD
patients would tend to be more religious than controls,
that children during early childhood should be more inter-
ested in religious ritual than at other stages of develop-
ment, and so on. Although there are connections
between certain forms of religious practice and obsession-
ality (Fallon et al. 1990; Hermesh et al. 2003), they fail to
support these general conjectures.
Figure 4 (Boyer & Lie
´
nard). A simplified model of action ritualization in cultural rituals. Boxes identity different functional systems in
the same way as in Figure 3. Participants in rituals are provided with two kinds of information, (a) statements about potential danger and
(b) scripted recipes for ritual action, that activate the security-motivation systems. Rules for ritual performance result in both goal-
demotion and low-level action-parsing with the resulting swamping of working memory. These processes result in highly attention-
demanding and compelling performance of rigidly scripted actions. This in turn makes the associations more salient, which should
make subsequent messages about ritual more intuitively compelling.
Boyer & Lie
´
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BEHAVIORAL AND BRAIN SCIENCES (2006) 29:6 17

9. Conclusions
9.1. Ritualization and cognitive adaptations
Our models of individual and cultural ritualization take as
a starting point a specific connection between obsessive
pathology and security motivation (Mataix-Cols et al.
2005; Szechtman & Woody 2004) but also a more
general set of assumptions about the adaptive character
of specialized neuro-cognitive function (Cosmides &
Tooby 1999; Duchaine et al. 2001). We have assumed
that the Hazard-Precaution system was the outcome of
selective pressure for gradually finer-grained inferential
detection of and appropriate response to recurrent
hazards in ancestral environments. This naturally leads
to the question, whether action-ritualization might consti-
tute a cognitive adaptation, in the same way as other
domain-specific capacities do (Cosmides & Tooby 1994).
The question should be more specific and bear on either
individual or cultural rituals, since the cognitive processes
involved are so different.
Let us consider cultural rituals first. In the anthropolo-
gical literature, there are various hypothetical models of
the ways in which participation in collective ceremonial
may have conferred adaptive advantage to individuals
(Burkert 1996; Knight et al. 1998; Rappaport 1999; Sosis
2000; Watanabe & Smuts 1999). This stems from a long
anthropological tradition of construing ritual as crucial to
social organization and cohesion (Durkheim 1947;
Hocart & Needham 1970; Smith 1889). We discuss the
various hypotheses in more detail elsewhere (Lie
´
nard &
Boyer 2006). Suffice it to say that these different models
may well explain a disposition to participate in coordinated
social action, but not why these common endeavors should
include scripted, goal-demoted, redundant scripting of
familiar actions.
The question of individual ritualization is more
complex. In our model, the activation of the Precaution
system normally results in performance of appropriate
actions from the Precaution Repertoire – and this, in
most circumstances, should produce enough of a closure
or satiety experience (Szechtman & Woody 2004) to pre-
clude reiteration. However, the closure experience prob-
ably is the outcome of continuous changes in the
relevant circuitry, leading to various degrees of repetitive-
ness and anxiety about proper performance. So, in our
model, it is not the ritualized behavior but the Precaution
system itself that constitutes a cognitive-motivational
adaptation. It has the hallmarks of such adaptations,
such as a specific class of inputs, a specific mode of oper-
ation, a particular series of fitness-enhancing conse-
quences, a non-trivial functional design – and, in this
particular case, a specific neural implementation as well
as specific impairment.
9.2. Phylogeny: Rituals and displays
What is the connection between human and other animal
“ritual”? We use scare quotes here, as the term is stretched
to encompass highly disparate forms of behaviors
(Gluckman 1975). Nevertheless, one should comment on
the obvious similarities between human rituals and various
forms of animal communication, notably in the context of
agonistic and sexual displays where stylized behavior,
repetition, and redundancy are clearly present. Is this
evidence for the deep phylogenetic ancestry of ritual? In
our view, this question suffers from several ambiguities:
First, although we may sometimes follow a “same
effects, same causes” rule of thumb, this is rather mis-
guided if it leads us to confuse observable behaviors with
the neuro-cognitive systems that support them (Povinelli
et al. 2000). Indeed, even in the limited domain of
human rituals, apparently similar behaviors (in patients
and in cultural ritual participants) actually stem from
very different cognitive processes. This should a fortiori
be expected when comparing widely different species.
Second, the question downplays the extent to which
certain features of behavior are constrained. Consider
OCD patients for instance. They are not motivated by a
positive urge to ritualize. Rather, ritualized behavior
happens to constitute an optimal response to the anxiety
produced by cognitive impairment. Other forms of beha-
vior would not seem appropriate given the anxious con-
cerns; they would not produce temporary relief. So the
redundancy, et cetera, in this case stems from the proper-
ties of action-parsing and precaution systems in humans.
Now consider animal displays. They are strongly con-
strained too, in this case by the logic of signaling processes.
For instance, signals must be clear and distinct enough to
preclude ambiguities, which typically results in redun-
dancy (Rowe 1999). The evolution of attentive receivers
requires that signals maintain a relatively high level of
accuracy (Bradbury & Vehrencamp 2000; Silk et al.
2000) and that the content of the signals be directly
related to the fitness dimensions they advertise
(Zahavi & Zahavi 1997). In other words, in both human
rituals and animal displays, features like stylization, redun-
dancy, and repetition are the outcome of external con-
straints, but these seem to be different in the two cases.
This would support the tentative conclusion that the
presence of “ritual” in both cases is a case of behavioral
analogy rather than the index of similar capacity and pro-
cesses. (Obviously, this is not to deny that humans like
other animals do engage in stereotypical displays, in situ-
ations of courtship or aggression). This is tentative in the
sense that we do not know much about the phylogenetic
history of ritualization (in the precise sense used here) in
the hominin line. The evidence so far simply does not
support the notion of a direct evolutionary homology.
9.3. Epilogue
It is a cognitive and evolutionary puzzle that humans
perform rituals, given the waste of time and resources
involved. We aimed to solve the puzzle by piecing together
the evidence from neuroimaging, neuropsychology, clini-
cal psychology, developmental studies, and evolutionary
anthropology. Ritualization may be seen as an occasional
by-product of specific precaution systems and action-
parsing capacities in humans.
This explanation however compels us to discard the
common intuition that there is a natural kind of phenom-
ena called “rituals.” If valid, our model does not explain
“rituals” but a highly specific form of behavior that is
found in many of them and occurs for different reasons
in the behavior of most normal children and obsessive
patients, on the one hand, and in the context of collective
rituals, on the other.
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18
BEHAVIORAL AND BRAIN SCIENCES (2006) 29:6

Discarding misleading categories of behavior (like
“ritual” – but there are many others) may well be the
inevitable consequence and benefit of proposing inte-
grated explanations. Our model is an attempt to bring
together neural systems, evolutionary background, beha-
vioral manifestations, and developmental trajectory to
the understanding of action-ritualization. We consider
this indispensable. True, much work remains to be done
to understand the phenomenon. For instance, the cogni-
tion of children’s ritual is still largely unexplored; the con-
nections between ritual performance and anxiety relief in
patients need a proper neurophysiological study; the per-
suasive power of cultural rituals is not properly explained.
But we are confident that all these and other puzzles will
be solved by the kind of “general behavioral science”
that transcends fields and discipline boundaries.
ACKNOWLEDGMENTS
We are grateful to Leda Cosmides and John Tooby for initial
inspiration, and to Dan Fessler, Thomas Lawson, Robert
McCauley, Pascale Michelon, Mayumi Okada, Tom Oltmanns,
Ilkka Pyysia
¨
inen, Howard Waldow, Dan Wegner, Harvey
Whitehouse, and Jeff Zacks, for detailed comments on a draft
version of this article.
Open Peer Commentary
Why ritual works: A rejection of the by-product
hypothesis
Candace Storey Alcorta
a
and Richard Sosis
a,b
a
Department of Anthropology, University of Connecticut, Unit 2176, Storrs, CT
06269-2176;
b
Department of Sociology and Anthropology, Hebrew University
of Jerusalem, Mt. Scopus, Jerusalem 91905, Israel.
candace.alcorta@uconn.edu richard.sosis@uconn.edu
www.anth.uconn.edu/faculty/sosis/
Abstract: We argue that ritual is not a by-product as Boyer & Lienard
(B&L) claim, but rather an evolved adaptation for social
communication that facilitates non-agonistic social interactions among
non-kin. We review the neurophysiological effects of ritual and propose
neural structures and networks beyond the cortical-striato-pallidal-
thalamic circuit (CSPT) likely to be implicated in ritual. The
adaptationist approach to ritual offers a more parsimonious model for
understanding these effects as well as the findings B&L present.
Why humans engage in “irrational,” costly rituals is a perplexing
evolutionary question. Boyer & Lienard’s (B&L’s) attempt to
answer this question through the integration of evolutionary,
neuropsychological, and neuroimaging evidence is an important
first step in understanding both the proximate and causal mech-
anisms of ritual. Their inclusion of childhood, life cycle, and
pathological rituals focuses attention on significant developmen-
tal, ecological, and population elements of ritual heretofore
ignored. Moreover, their consideration of underlying neuro-
physiological components offers insights into specific neural
pathways implicated in ritual behaviors. These elements are sig-
nificant advances in the evolutionary study of ritual. Unfortu-
nately, the model developed from this promising foundation
fails to fulfill the potential of their approach. Most significantly,
the authors’ conclusion that “ritualization may be seen as an
occasional by-product of specific precaution systems and
action-parsing capacities in humans” (target article, sect. 9.3)
does not adequately explain the data presented throughout
their discussion or advance our understanding of why ritual
occurs so ubiquitously and frequently across species. We argue
that a more compelling approach views ritual as behavior
evolved for social communication that optimizes appraisal and
learning, and facilitates non-agonistic social interactions among
non-kin.
Laboratory experiments have shown that the core elements of
ritual, that is, formality, pattern, sequence, and repetition,
heighten and focus attention, promote associational learning,
and enhance long-term memory (Rowe 1999). As noted by
B&L, ritualized behaviors are neither routine, nor automatic,
but instead require “high cognitive control.” B&L argue that
such control results in the “swamping” of working memory
which permits the temporary suppression of intrusive thoughts.
They claim, however, that ritual performed on a long-term
basis has the “ironic outcome” (sect. 7.3) of actually strengthen-
ing such thoughts. In contrast, we view this effect of ritual to be a
functional adaptation rather than an “ironic outcome.” Neuroi-
maging studies have shown that tasks of sustained attention or
vigilance increase activation of right hemisphere prefrontal and
superior parietal cortices (Pardo et al. 1991). Increased right
hemisphere activation has several important consequences: it
promotes social-emotional information processing (Tranel et al.
2002); it forefronts negative appraisal systems (Cacioppo et al.
2002); and, it elicits holistic, gestalt thinking. Recent research
has also shown that the right posterior association cortex is par-
ticularly important in the processing of new information, as
well as in anticipating consequences and determining emergency
reactions (Schutz 2005). Ritual’s ability to engage these various
right hemispheric functions, and its promotion of associational
learning and strengthening of long-term memory would be
particularly important in relation to complex social decisions
involving unrelated and potentially dangerous conspecifics. It is
precisely under such circumstances that ritual occurs in
humans and nonhumans alike. In addition to right hemispheric
dominance effects, the core elements of ritual are also likely to
activate neural structures and pathways specific to the brain’s
vigilance and reward systems.
B&L review neuroimaging evidence regarding the cortico-
striatal circuits implicated in obsessive-compulsive disorder
(OCD) ritualization. Although they propose a specialized “Pre-
caution/Hazard” brain module, their discussion of neurophysio-
logical pathways stops short of incorporating mesolimbic and
corticolimbic vigilance and reward networks associated with the
cortical-striato-pallidal-thalamic circuit (CSPT) (Cardinal et al.
2002; Dehaene & Changeux 2000). These pathways encompass
limbic structures, such as the amygdala, which are critical for
evaluating stimuli in relation to both physical and social threat
(Adolphs 2002; Dolan 2000). They also include structures funda-
mental to the brain’s reward system, such as the nucleus accum-
bens. While the amygdala has been shown to be critical for social
judgments of trust (Adolphs 2002; Morris et al. 1998), recent
neuroimaging studies show that the nucleus accumbens and
other reward system structures are activated during episodes of
mutual cooperation (Rilling et al. 2002). Both the amygdala
and the nucleus accumbens are critical components in motiva-
tional pathways for approach/avoidance (Cardinal et al. 2002;
Dehaene & Changeux 2000). These structures also provide eva-
luative input to the orbitofrontal cortex that is critical for both
social judgment and effective personal decision-making
(Dehaene & Changeux 2000; Schoenbaum et al. 2003). The
dopaminergic corticostriatal associational networks that encom-
pass orbitofrontal, limbic, and basal ganglia structures undergo
a developmental shift during adolescence (Spear 2000). As we
have discussed elsewhere (Alcorta & Sosis 2005), these pathways
constitute likely neural networks for learning and emotionally
valencing both the signals and symbols of ritual. These pathways
encompass the neurophysiological counterpart of the “Precau-
tion/Hazard” brain module proposed by B&L. In sharp contrast
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to their model, however, we view ritual as an evolved adaptation
that activates these pathways, rather than as a dysfunctional
by-product of their operation. We propose that ritual activation
of the cortico-limbic-striatal networks kicks socio-emotional
appraisal and learning processes into high gear and initiates
right hemispheric processing of the complex cost/benefit calcu-
lations associated with approach/avoidance decisions that lie at
the heart of non-agonistic social interaction between unrelated
conspecifics.
If the capacity for ritual is an evolved adaptation, then individ-
ual genetic propensities for ritual should display variation
throughout a population. B&L note that just such variation has
been proposed as an explanation of OCD. Ritual also exhibits
considerable ontogenetic and socioecological malleability, as
well (Alcorta & Sosis, forthcoming). The continuum of simple
to complex behaviors found in both human and nonhuman
ritual clearly includes a broad range of both “fixed” and
“learned” elements. Within many species, such as songbirds
(Marler 1999) and baboons (Watanabe & Smuts 1999), learning
is both a necessary and developmentally sensitive component of
ritual. As noted by B&L, and as we have discussed elsewhere, this
appears to be true of human ritual, as well (Alcorta 2006).
Although the capacity and the propensity for learning such beha-
viors is genetically encoded in each individual, the activation and
development of the neural pathways specific to such behaviors
requires that learning occur through social transmission. Such
learning may be optimally accomplished during particular
“experience expectant” developmental periods (Greenough
1986). This model of ritual predicts that ritualized behaviors
will vary across the population, will occur predominantly in
relation to social concerns, and will display a range of intensity
and expression in response to differing individual, developmen-
tal, life cycle, and ecological factors. These predictions are
borne out by the human data presented by B&L and by etholo-
gical research (Ball 1999; Marler 1999; Rogers & Kaplan 2000;
Wingfield et al. 1999).
A robust evolutionary theory of ritual requires that we consider
both human and nonhuman data, and that we shed false
individual/cultural dichotomies, as well. Unlike the by-product
theory of ritual, a theory of ritual as an evolved adaptation for
social signaling and communication provides a parsimonious
and integrated explanation of all the relevant data across disci-
plines and across species. Testing hypotheses derived from this
theory can move us forward in understanding both the proximate
and ultimate causes of ritual.
Compulsions and cultural rituals: The need for
a drive-motivational framework
Ralf-Peter Behrendt
MRC Psychiatry, The Retreat Hospital, York, YO10 5BN, United Kingdom.
rp.behrendt@btinternet.com
Abstract: Instinct theory parsimoniously clarifies the relationships
between emotions, such as fear and anxiety, and perceptions, thoughts,
and actions. Its acceptance allows more elegant insights into riddles of
obsessions and compulsions. Their relationship to anxiety and
dysexecutive function needs to be explained, as does their characteristic
egodystonia, while avoiding the pitfalls of cognitivist, empiricist, and
teleological thinking.
Left to itself, reason is like a ... wonderful system of wheels within
wheels, without a motor to make them go round. The motive power
that makes them do so stems from instinctive behaviour mechanisms
much older than reason and not directly accessible to rational self-
observation. ... These deep strata of the human personality are, in
their dynamics, not essentially different form the instincts of animals,
but on their basis human culture has erected all the enormous
superstructure of social norms and rites whose function is so closely
analogous to that of phylogenetic ritualization.
— Konrad Lorenz (1963/2002, p. 240)
McDougall (1924), who regarded instincts as the “prime movers
of all human activity,” discerned that the operation of each
instinct “is accompanied by its own peculiar quality of experience
which may be called a primary emotion” (p. 128). Fear is the
“characteristic emotional accompaniment” of the “instinct of
escape,” which enacts, first, “a running to shelter” and, second,
“a lying hid when the shelter has been attained” (pp. 150–51).
For gregarious species, shelter may be represented by “the
mass of the congregated herd.” A loud noise “is perhaps the
most nearly universal key” to the “gates of fear,” another being
“the sudden move of a large object” (p. 152). The impulse of
the gregarious instinct is to approach conspecifics. Uneasiness
and restlessness, and a craving to be back in the company of
others, afflict the individual on his absence from the group
(McDougall 1924). The likely emotional accompaniment of the
gregarious instinct – anxiety – may be similar to that of the
instinct of escape, suggesting the two instincts are evolutionarily
related.
Situations or objects are perceived because “they are specific
excitants of these instincts” (McDougall 1924, p. 273). An
object recognised or thought about “evokes in [the subject] an
impulse to effect some change”; conative experience in pro-
portion to the strength of the underlying instinct – as the “felt
impulse to action,” – is integral to all our “sense-impressions”
(p. 265). Thus, certain cues evoke fears of contamination,
which lead to washing or cleaning rituals. Other cues evoke con-
cerns about intrusion by others, leading to checking rituals, but
anxiety indeed forms an important context for compulsive
actions. Perception of threats and ideas about possible threats
may represent displacements – unconscious attempts to
convert overwhelming anxiety into concrete forms of fear that
allow specific responses in form of specific rituals. The subject’s
attention to potential threats may be heightened inasmuch as his
anxiety cannot be resolved through secure interpersonal related-
ness (Heidegger’s [1927/1962] notion of “fleeing anxiety”). Com-
pulsive actions, then, may relieve a specific fear – the immediate
motivational impetus behind these actions – but they would not
substantially alter the background of anxiety. “Goal-demotion”
(see target article) of normal fear responses and their repetition
would be due to the fact that the ultimate motivational
force – existential anxiety – is not addressed.
Although “patients who perform more rituals are typically
more anxious,” this does not mean that anxiety is one of “the
long-term effects of ritual performance” (target article, sect.
7.3). If anxiety does increase in the course of obsessive-compul-
sive disorder (OCD) then this may be due to social debilitation.
Conversely, helping the patient in therapy to develop secure
interpersonal relatedness addresses his anxiety and can reduce
obsessions and compulsions (Gabbard 1990). The key difference
between normal “ritualized action-plans to avoid [...] dangers”
(sect. 7.1, para. 1) and pathological compulsions may not lie in
“appraisal” of dangers but in the presence or absence of back-
ground anxiety. Specific fears can be abreacted under most cir-
cumstances, but anxiety often cannot – because secure social
relatedness may be beyond reach for the individual, particularly
if impulsivity is a confounding problem.
Much of social behaviour is determined from a drive-motiva-
tional perspective by successive impulses of “aggression, fear,
protection-seeking and renewed aggressiveness” (Lorenz 1963/
2002, p. 55). In phylogenesis, ritualisation creates new instinctive
motor patterns by welding together conflicting impulses (Lorenz
1963/2002). The display of such behaviours often acquires signal
function in social situations. Submissive gestures are ritualised
behaviour patterns that elicit in members of the same species
an active inhibition against aggression. Norms of social behaviour
developed by cultural ritualisation started to play an important
part in human society “when invention of tools was beginning
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to upset the equilibrium of phylogenetically evolved patterns of
social behaviour” (p. 249). Social manners represent “culturally
ritualised exaggerations of submissive gestures most of which
probably have their roots in phylogenetically ritualised motor
patterns conveying the same meaning” (p. 77).
Illness or misfortune may provide occasions for complex cul-
tural rituals indeed, but it makes sense to insist that their func-
tion – like that of social manners – is to foster social cohesion
in complex societies. What makes collective rituals attention-
grabbing and compelling is not their presumed ability to “activate
the Hazard-Precaution system by including cues for potential
danger” (sect. 8.5, para. 2); instead, their compelling nature
and stability within traditions may stem from their role as a
socially acceptable outlet for instinctive intraspecific aggression
and culturally appropriate medium for negotiation of rank
order. Participation in cultural rituals – and adherence to social
norms in general – is not compulsive, but compulsory – that is,
demanded by the group – insofar as it deflects instinctive intras-
pecific aggression from the group and signals submission and
conformity. Deviation from norms and rituals is dangerous
indeed because it leads to social rejection; and it is in this
sense that fear plays a role.
Boyer & Lienard’s (B&L’s) suggestion that their attempt to
“explain a disposition to participate in coordinated social
action” stands out from other such attempts in that they resolved
“why these common endeavors should include scripted, goal-
demoted, redundant scripting of familiar actions” (sect. 9.1,
para. 2), attests to today’s ignorance of Lorenz’s work. In contrast
to Lorenz, B&L dispute that “obvious similarities between
human rituals and various forms of animal communication,
notably in the context of agonistic and sexual displays” could be
seen as “evidence for the deep phylogenetic ancestry of ritual”
(sect. 9.2, para. 1). Their model demands that apparently
similar behaviours “actually stem from very different cognitive
processes,” – suggesting, for instance, that in animals “signals
must be clear and distinct enough to preclude ambiguities.”
However, human cultural rituals too have a signal function:
they signal social assertion or submission in aggressively motiv-
ated competition within the group for ranking positions and
resources.
Obsessive and compulsive phenomena are not just exaggerated
versions of risk avoidance behaviour, as B&L maintain. Compul-
sions and obsessions are characteristically egodystonic; they are
accompanied by inner resistance reflecting a conflict between
drives. This is usually between an urge to escape a specific
hazard and fear of aggression. Expectations of punishment,
which relate to patients’ preserved insight into the abnormality
and social unacceptability of their compulsions – psychoanalyti-
cally conceptualised as fear of the superego – are the source of
much of their suffering. Obsessive thoughts about harming or
offending others indeed elicit fears of social ostracism, represent-
ing a conflict between the individual’s aggressive drive and his
fear of becoming the target of others’ aggression.
Rather than linking obsessive-compulsive disorder (OCD) to
“a dysfunction in a satiety signal, plausibly generated in brain-
stem structures” (sect. 3.3, para. 4; emphasis in the original),
we should emphasise the motivational instability between con-
flicting drives, ultimately between existential anxiety urging
human relatedness (transformed into a specific fear) and the
fear of aggression. As B&L recognise, “conflict in groups threa-
tens each member’s access to resources,” so that the motivational
conflict derives its immediacy precisely from the “human depen-
dence on conspecifics for all aspects of survival” (sect. 5.4.3).
These conflicts would be expected to activate the anterior
cingulate gyrus in patients with OCD, consistent with findings
by Fitzgerald et al. (2005), bearing in mind that the anterior
cingulate cortex is more likely a structure representing basic
motivational/emotional states, including fear and anxiety
(Behrendt 2005; Ploghaus et al. 2003), rather than an “error-
detection network” (Winterer et al. 2002). What may be of
greater pathophysiological relevance is the association of OCD
with prefrontal lobe/basal ganglia pathology, given that compul-
siveness is clinically related to impulsivity – part of the dysexecu-
tive syndrome.
What else is driving ritualized behavior,
besides the “Hazard-Precaution system”?
Developmental, psychopathological, and
ethnological considerations
Oana Benga
a
and Ileana Benga
b
a
Department of Psychology, Babes-Bolyai University Cluj-Napoca, 400015
Cluj-Napoca, Romania;
b
Folklore Institute of the Romanian Academy, 400015
Cluj-Napoca, Romania.
oanabenga@psychology.ro ileana_benga@yahoo.it
www.psychology.ro
Abstract: The target article presents arguments for a motivational system
dedicated exclusively to the detection of, and reaction to, particular
threats to fitness, the so-called “Hazard-Precaution System,” which,
according to the authors, drives ritualized behavior. We approach
the issue of a motivational system from three perspectives –
developmental, psychopathological, and ethnological.
The goal of an integrated model of ritualized behavior, put
forward by Boyer & Lienard (B&L) in the target article, is
both ambitious and laudable. Yet the search for commonalities
might sometimes overlook differences between partly or superfi-
cially similar phenomena. Like the authors, we approach from
three perspectives – developmental, psychopathological, and
ethnological – a key aspect in this search: the issue of a motiva-
tional system dedicated exclusively to the detection of, and
reaction to, particular threats to fitness, the so-called Hazard-
Precaution system, driving ritualized behavior.
From a developmental perspective, one of the major claims by
B&L draws our attention: that ritualized behavior cannot be
routine-like or automatic, but rather, requires high-order cogni-
tive control. The distinction between routines and rituals per se is
conceptually a worthy one. However, there is a corollary claim
that rituals involve an explicit emphasis of the agent on his or
her own proper performance of actions – and, at the clinical
end, that rituals even involve a patient’s recognition of his own
irrationality. But this self-reflection or autonoetic consciousness
(Tulving & Markowitsch 1998) involves a degree of metacogni-
tion which is not easily present in the cognitive system of 2 to 4
years old children.
The positing of such self-consciousness is even more proble-
matic with regard to what is the most flourishing period of com-
pulsive behavior in normal children, that is, age 2 to 4 years (see
Evans et al. 1997). Evans and Gray (2000) have suggested that
younger mental age groups (MA) (2–5 years) exhibit a greater
number of ritualistic behaviors than do older ones. Yet, far
from functioning maturely, some “basic ingredients” of self-
reflection are barely emergent during the same age interval:
ingredients such as, self-concept (Howe & Courage 1993;
Povinelli et al. 1996), understanding mental representations
(Perner & Ruffman 1995), and episodic thinking about the
personal past (Nelson 1993; Welch-Ross 1995) and future
(Atance & O’Neill 2005). Therefore, it might be worthwhile to
further explore the very construct of ritualization as proposed
by B&L, in relation to early childhood compulsive behaviors.
In exploring the early beginnings of ritual behaviors, a closer
look at child development suggests a possible link with knowl-
edge structures, for example, scripts and narratives, rather than
with fear management.
Script theory (Schank & Abelson 1977) assumes that people
have generic knowledge structures that reflect an understanding
of the temporal and causal sequences of actions. For early
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childhood, scripts are considered basic building blocks of
cognition (Nelson 1986, 1996). Children easily establish these
forms of knowledge representation when encountering repeated
events (Bauer & Mandler 1990). Already at ages 1 to 2 years,
children can retain and reproduce causal, temporal, and goal-
directed structures of events (Bauer et al. 1998). Scripts
become increasingly abstract or schematized with experience
(Fivush & Slackman 1986). However, Farrar and Goodman
(1992) indicate that younger children (aged 4 versus 7) are
more schema-dependent when encoding an event.
Higher prevalence of ritualistic behavior, synchronized with
the prevalence of script knowledge structures, may signal a
child’s need for cognitive mastery of the environment (see also
Piaget 1952). Computational economy, rather than the notion
of reaction to inferred threats to fitness, could better explain
such a rich cognitive and behavioral canonical repertoire.
Shifting now to child psychopathology, one particular case
unexplored by the target article is that of autistic spectrum dis-
orders. Here again, rituals, as cornerstone psychopathological
features, are performed without any clear connection to threat
avoidance. “Need for sameness,” restrictive interests, and repeti-
tive behaviors are classical autistic symptoms (Kanner 1943). But
autistic rituals are performed out of the realm of consciousness.
And more basic brain mechanisms involved in change detection
seem to function atypically in this case: people with autism have
some difficulty in involuntary attention switching when
processing unexpected infrequent stimuli (Gomot et al. 2006).
Behavioral, ritualistic “avoidance of change” would then be a
secondary dysfunction, an adaptive behavior aimed at keeping
the environment as predictable as required by such an atypical
neural/cognitive system.
The ethnological approach distinguishes coercion within tra-
dition from compulsion within individual threat-responding
ritual behavior.
In order to locate the segment of tradition we are addressing,
we need to temporarily set aside the questions of origins of orally
transmitted cultural facts. These are hardly reducible – in both
shape and content – to sharply and easily recognizable items
such as rituals, customs, and narratives. Therefore, we may
safely hypothesize that their incidence at a given moment in
time, for a certain community, represents far more than the
sole transmission from a previous segment of time, subdued to
rigidity within tradition; a snare of relations that makes both cer-
emonials (individually or collectively performed) and narratives
(individually and collectively produced) be strongly a matter of
active creativity, just as they continue to be a matter of “adher-
ence to script” (see target article, sect. 2.5). Field results we
were able to collect from within what we call Romanian folkloric
culture of today, vividly show a continuum among folkloric
genres of enacted tradition-transmitted knowledge (Benga
2005): to quote but one example, the complex choreutic
therapy performed by the ritual dance of Ca
˘
lus¸ is explicitly
linked to abundant local narrated mythology about the specific
trance-like disease called luatul din iele, and about the mythic
culprits – a category of fairies. Yet, new forms of coercion have
lately replaced the old motivations, in the form of competition
for stage virtuosity on the occasion of socialist-time flavored fes-
tivals. The ethnologist is himself compelled to treat these with
just as much seriousness as he does treat the confessions of old
peasants – because what he witnesses today is precisely one of
several forms of survival of the old ceremonial/ritual dancing:
in other words, a genuine form of cultural transmission.
This is why we favor, as much more fertile, the concept of
“salient memories” in analyzing the transmission of tradition
(Boyer 1990, pp. 8–20), over the somehow restrictive, although
method fueling, framework that delineates religious behavior in
cognitive terms (Boyer 1993, pp. 4–18; cf. target article, sects.
8.2, 8.3). For, whatever learning process our brains might be pre-
pared for, that fact alone shall not provide a religion to the bearer
(Boyer 2001a, p. 13) – which brings us nicely back to the subtle
relation between the “what” and the “how” of transmission, be it,
successively, more orally, or more ritually, salient.
Ritualized behavior in animals and humans:
Time, space, and attention
David Eilam
Department of Zoology, Tel-Aviv University, Ramat-Aviv 69978, Israel.
eilam@post.tau.ac.il http://www.tau.ac.il/ eilam
Abstract: A study of the organization of obsessive-compulsive disorder
(OCD) rituals in time and space illuminates a postulated mechanism
on shifting focus in action parsing, from mid-ranged actions to finer
movements (gestures). Performance of OCD rituals also involves high
concentration rather than the automated, less attended performance of
rituals in normal and stereotyped behaviors in animals and humans.
The target article suggests that two systems may account for the
occurrence of ritualized behavior. One system is of “inferred
threats to fitness,” the second is of “action-parsing.” Manifes-
tation of movement parsing is overt and the actions that comprise
rituals are visible and measurable by virtue of animal behavior
studies that have scrutinized ritualized behavior, developing
conceptual frameworks and analytic tools that are also applicable
in studying ritualized behavior in patients with obsessive-
compulsive disorder (OCD). Indeed, recent utilization of such
an approach in studying OCD rituals (Eilam et al. 2006) revealed
facets that coincide with the question raised by Boyer & Lienard
(B&L). Specifically, the outstanding question is not only as posed
in the target article, “why ritualized behavior,” but also where
and how does ritualistic behavior occur. “Where” refers to the
typical coupling between rituals and specific locations or
objects; “how” refers to the high concentration involved in com-
pulsive performance.
In the target article, action parsing is described at three levels
that correspond to those offered by Zacks and colleagues
(Zacks & Tversky 2001; Zacks et al. 2001b) as: (1) simple gestures;
(2) behavioral episodes; and (3) script. B&L hypothesize that an
excessive focus on the level of simple gestures is what happens
in cultural and individual rituals, in contrast to spontaneous focus-
ing on the mid-ranged behavioral episodes in normal behavior.
Indeed, this is precisely what was revealed when tools derived
from studying the quinpirole-treated rat model of OCD (Ben-
Pazi et al. 2001; Szechtman et al. 1998) were applied in studying
rituals in OCD patients (Eilam et al. 2006). Parsing categories
became obvious when described in the context of the location or
object at which they were performed, especially since OCD
rituals carry a remarkable spatial component with a strong affinity
between compulsion and specific location or object (Eilam et al.
2006). Specifically, the space in which a ritual (¼ behavioral
episode) is carried out may be viewed as the set of sites or
objects at which actions (¼ movements or gestures) are performed.
Behavior can then be scored by notating the movements at each
location/object. This is illustrated in Table 1, describing the
OCD ritual of car-locking.
First, the patient’s ritual was divided into two distinct domains
in which it was executed: acts performed inside the car (Table 1),
and those performed outside the car (not shown here). Then, the
locations at which the patient displayed acts were identified as
the ignition key, light switch, and so on (top rows in Table 1).
Finally, the set of acts in each of these locations was scored in
terms of a verbal description of the acts. The resulting descrip-
tion shown in the table provides the sequence of acts, highlight-
ing the repetitive performance in the OCD patient compared
with a control individual who was asked to execute the same
action (bottom of Table 1). The entire sequence of the control
individual took 11 seconds, compared with 63 seconds taken by
the OCD patient. The excessive duration of the OCD ritual
was thus generated by the repetitive manner of the compulsive
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ritual, which becomes apparent when the number of acts
(¼ gestures) is summed for each location, resulting in 30 acts
(6 þ 4 þ 5 þ 13 þ 2) for the OCD patient, compared with four
acts (2 þ 0 þ 0 þ 1 þ 1) for the control individual who performed
the same task of car-locking (¼ script). Moreover, a comparison
of acts (gestures) at the various locations (episodes) in 14 OCD
rituals revealed that there were 1–3 locations at which acts
were repeated significantly more than any of the control
movements, resulting in the repetitive manner of OCD rituals
(¼ many repetitions of the same few movements). Thus, as
suggested in the target article, OCD rituals consist of excessive
focus on simple gestures (movements). Our current data
(Eilam et al. 2006) add to this a spatiotemporal component: ges-
tures are coupled with specific locations, and gesture repetition
accounts for the extended ritual duration.
A central contention of the target article relates to the high
concentration involved in displaying ritualized behavior.
Indeed, the vigor, precision, and high concentration of OCD
patients when displaying their rituals is striking to a bystander.
B&L suggest that a swamp of working memory and an urge for
precise performance account for the high concentration, result-
ing in the ironic outcome of higher anxiety in patients with
more rituals. Our study adds to this the finding that high concen-
tration is the discriminator of compulsive rituals from other
rituals in animal and human behavior (Serruya & Eilam 1996).
Repetitive, stereotyped, or well-practiced performance in
animals and humans has been suggested as a mechanism for
minimizing the involvement of information-processing systems
that are required for motor performance, enabling the direction
of attention elsewhere (Fentress 1976). For example, when
driving along an unfamiliar road we are required to concentrate
more compared with driving along a familiar road, where we are
more relaxed and may direct attention elsewhere. In animals,
familiar paths enable directing attention to other aspects of the
environment, such as the presence of potential predators
(Serruya & Eilam 1996). Thus, unlike compulsive rituals, other
rituals involve lowered attention.
Nonetheless, the link between attention and performing rituals
is bidirectional and rituals may be constructed in order to con-
centrate and avoid goal-demotion, as, for example, the intensive
religious rituals that enhance concentration during rigorous
prayer, or sportsmen rituals that facilitate concentration in per-
formance and disassociation from spectators. In all, although
some of B&L’s contentions, such as the “threat to fitness” may
remain hypothetical in being hard to assess or quantify, the
data collected during our observations on OCD patients strongly
support several of B&L’s measurable hypotheses.
Contextual features of problem-solving and
social learning give rise to spurious
associations, the raw materials for the
evolution of rituals
Daniel M. T. Fessler
Center for Behavior, Evolution, and Culture, and Department of Anthropology,
University of California, Los Angeles, Los Angeles, CA 90095-1553.
dfessler@anthro.ucla.edu
http://www.sscnet.ucla.edu/anthro/faculty/fessler/
Abstract: If rituals persist in part because of their memory-taxing
attributes, from whence do they arise? I suggest that magical practices
form the core of rituals, and that many such practices derive from
learned pseudo-causal associations. Spurious associations are likely to
be acquired during problem-solving under conditions of ambiguity and
danger, and are often a consequence of imitative social learning.
Boyer & Lienard’s (B&L’s) model describes the underpinnings
of a Sperberian attractor (Sperber 1996, Ch. 5) in the cultural
Table 1. Car-locking ritual in OCD patient (A) and control individual (B)
LOCATION/OBJECT
Ignition key Light switch Steering wheel Gear stick Other actions
A. Ocd Patient
Switch engine off
Take out the key fSwitch on and offg3
Insert the key
Switch on and off Hold it Lock it
fMove it forth and backg4
Press it down
fMove it forth and backg2
Rotate left Press it down
fMove it forth and backg2 Collect handbag
Rotate right
Switch on and off
Take out the key Rotate right
Rotate left
Switch on and off Move it forth and back
Press it down Get out of the car
Total acts:
64 513 2
B. Control Individual
Switch engine off
Take out the key Lock it Get out of the car
Total acts:
20 01 1
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evolution of rituals: the model generates the prediction that prac-
tices that produce the appropriate load on working memory are
more likely to be maintained and spread, as they have an addic-
tive component to them, temporarily ameliorating, but ultimately
exacerbating, panhuman concerns. While this usefully explains
why many rituals share core features, it does not address how
rituals arise. To complement the authors’ model, I therefore sum-
marize here (with no claim to originality) some possibilities in
regard to the latter, based on the premise that magical practices
lie at the root of rituals, and spurious associations lie at the root of
magical practices.
The relationship between actions and consequences is often
difficult to discern. Consequences may be delayed, making the
effects of actions unclear, or actions may be efficacious only in
the presence of an undetectable mediator, such as microbes,
that is sometimes absent. Ambiguity regarding the relationship
between actions and consequences opens the door to learning
spurious associations – people will often erroneously conclude
that a given action produces a given consequence (cf.
Bruner & Revusky 1961). This is particularly likely when no
readily discernable avenues for influencing events exist – when
the solution to a problem is not obvious, people will expand the
scope of prior actions with which they compare a given
outcome (cf. Gmelch 1978). Furthermore, both the acquisition
of spurious associations and their stability over time will be
enhanced when the goal involves avoiding substantial harm, as
this simultaneously increases the benefits of searching for poss-
ibly efficacious actions and the costs of systematically putting
such actions to the test.
Readers will recognize here elements of Malinowski’s (1948)
“theory of the gap”; paralleling aspects of B&L’s model, Mali-
nowski argued that magic arises as an attempt to assuage
anxiety in situations of uncertainty and danger. Disaggregating
the uncertainty of a situation and the anxiety generated by a situ-
ation, Felson and Gmelch (1979) found that both uncertainty and
anxiety increase the use of magic, and that these effects are inde-
pendent; that is, the anxiety attending a situation is a product of
the stakes at issue, not of uncertainty. These findings are consist-
ent with the factors postulated above – uncertainty is equivalent
to ambiguity as to the most effective course of action, while
anxiety reflects the goal of avoiding substantial harm. Note,
however, that whereas Malinowski, like B&L, focuses on the
anxiety-reducing function of the performance of magical
rituals, I seek to highlight the contextual determinants of the
acquisition of spurious associations – although the performance
of magical rituals may indeed serve intrapsychic goals, uncer-
tainty and danger lead to problem-solving strategies likely to
generate spurious associations regardless of their affective
consequences.
B&L stress that, to properly tax memory, rituals must involve
multiple components, to be carried out with precision.
Although spurious associations can be simple (e.g., a lucky
rabbit’s foot), such associations will often achieve the complex-
ity demanded by B&L’s model. All actions are potentially multi-
plex, as even simple motions can be broken down into many
constituent movements. Because the causal contribution of
any given facet of a multiplex action (a) is difficult to discern,
and (b) can only be determined by process-of-elimination
experimentation that is frequently avoided due to cost, actors
will often attempt to reproduce an apparently efficacious
action in its entirety. In turn, attempts to maintain complete
fidelity in subsequent iterations lead to memory-taxing recipes
of minutely specified behavior.
Spurious associations will often be produced by social learn-
ing. Imitating successful individuals can be an effective
problem-solving strategy. Whenever it is difficult to identify
which aspects of a successful individual’s behavior led to her
success, learners benefit from maximal fidelity of imitation,
with the result that many irrelevant behaviors are incorporated
into the action sequence (Richerson & Boyd 2004). The
situation is complicated by the fact that, in the absence of
explicit pedagogy (something frequently missing in small-scale
societies; Fiske, n.d.), even if the target of imitation under-
stands which actions are actually efficacious, this distinction is
easily lost during the process of imitation. Hence, the version
of the action practiced by the learner will often become more
complex than that practiced by the target. Iterated over mul-
tiple generations, the number of spurious associations incorpor-
ated into an action sequence can grow large. As the behavior
becomes more complex, it necessarily also becomes harder to
learn, whereupon mastery of the behavior can become an
index of the intimacy of the learner’s relationship with the pres-
tigious target (see Henrich & Gil-White 2001). Because simi-
larity to the target then generates prestige-by-proxy, a new
goal – prestige acquisition – is introduced; because this goal
is independent of the original pragmatic objective, its introduc-
tion further decreases the likelihood that spurious associations
will be ferreted out and discarded.
The authors note that both completeness and sequentiality are
heavily emphasized in ritual behavior. Both are also often
features of complex behaviors that are efficacious, hence actors
may adopt a quasi-ritualistic approach as a practical strategy –
many rock climbers, for example, always follow the same
sequence in donning their equipment. Observation suggests
that such actions often become imbued with some of the psychol-
ogy of rituals, as faithful reiteration of the specified actions leads
to a reduction in anxiety, whereas interruptions or modifications
enhance anxiety (cf. Gmelch 1978). This likely augments the con-
cretization of a particular form of behavior – although equally
effective alternative methods may exist, their negative affective
entailments preclude their utilization. Although such behavior
constitutes only a nascent ritual (since the actions are goal-
directed and effective), when combined with social learning,
this kernel may become increasingly ritual-like.
Pragmatic features of problem-solving and social learning thus
make it likely that individuals will often acquire spurious associ-
ations. This result is particularly likely among persons having low
evidential criteria (Brugger & Graves 1997) (probably including
most children), making some individuals more vulnerable to
the acquisition of spurious associations than others. Associations
that are sufficiently complex and sequential as to overload
working memory constitute the raw materials out of which
rituals are born; these, in turn, are refined by cultural evolution.
The rituals of explanation
Jeffrey Foss
Department of Philosophy, University of Victoria, Victoria, British Columbia,
V8W 3P4, Canada .
jefffoss@uvic.ca
http://web.uvic.ca/philosophy/aboutus/faculty.php
Abstract: Boyer & Lienard’s (B&L’s) explanation of ritualized behavior is
plausible because it fits so well with elementary facts about evolution of
plasticity in our behavioral repertoire. Its scope, however, may be
broader than its authors explicitly admit. Science itself may be
illuminated as ritual behavior. Science, like other rituals, can sustain
both healthy and pathological forms.
One ritual of scientific explanation is to begin with a grand theory
that later is qualified (sometimes to within an inch of its life) to
yield a modest proposal. As Boyer & Lienard’s (B&L’s) title
announces, they propose to explain “Ritualized Behavior” – and
this is very exciting, Newtonian, one might say, in its scope. Just
as Newton’s physics explained terrestrial and celestial motions in
one theory, so B&L propose to explain the full spectrum of ritual,
from non-pathological forms like religion to unhealthy forms like
obsessive-compulsive disorder (OCD). This heady promise
propels readers through the article, where we observe the
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ritual death by a thousand cuts of the grand theory. It can only
come as a disappointment to discover B&L saying, “Ritualized
actions are not ‘rituals’” and “Cultural ritual is not individual
ritual writ large” (sect. 8.6; B&L’s italics): this is no doubt true,
but what, then, are we to make of their earlier explanation of reli-
gious rituals and cultural ceremonies? And when they urge us to
“discard the common intuition that there is a natural kind of
phenomenon called ‘rituals’” (sect. 9.3), we might wonder what
it is, then, that they take themselves to be explaining. B&L’s
answer is that theirs is merely a modest proposal to explain
only the urge (sect. 8.2, para. 2) of individuals towards ritual,
not its social organization.
This is in no way to say that this is a bad theory. In fact, I think
it is a very good theory, one that illuminates ritual in an interest-
ing way: OCD is a behavioral analogue of an auto-immune
disease, a quite useful protective mechanism that has gone
awry; religion is a harmless, if idle, capture of the same precau-
tionary mechanism during its “calibration” (or recalibration).
What this good science leaves out is itself – or so I will
argue. Science, too, is, (at least in part) a ritual.
The plausibility of B&L’s theory derives not so much from
successful tests of it as from elementary facts about evolution.
For example, complex multi-cellular organisms evolved from
relatively simple single-celled organisms. The behavior of the
simplest organisms is ritualized in the sense defined by B&L
(see target article, Abstract): a single cell, for instance, has
receptors on its surface which swing into action automatically,
transferring materials into the cell stereotypically, rigidly,
repetitively, and mechanically (without rational motivation). By
contrast, the food-seeking, predator-avoiding, competitor-
besting behavior of complex organisms is creative, plastic, orig-
inal, and rational. The evolutionary strategy of Homo sapiens
has been to free behavior from totalitarian genetic control so
that individuals can adapt within their own lifetimes to the con-
ditions that obtain, rather than waiting for the creeping, tectoni-
cally slow, genetic adaptation of behavior. Intelligence and
learning permit a more rapid form of natural selection, namely
selection for adaptability of behavioral repertoire.
So, what really demands explanation is how human behavior
overcame ritualization, rather than how it remains in some
ways ritualized. And yet, despite the fact that that their explana-
tory goal goes in precisely the opposite direction, it is B&L’s pre-
suppositions about the process of overcoming ritual that makes
their explanation of ritualized behavior plausible. History
teaches us that it is the unexpected explanatory dividends of a
theory that convince us it is true, not the specific phenomenon
it was cooked up to explain in the first place. This is the case
with B&L’s model. It assumes that our ancestors’ Precaution
System was a healthy evolutionary product with two components,
a Potential Hazard Repertoire (sensory mechanisms that enabled
the recognition of specific hazards) and an Evolutionary Precau-
tion Repertoire (motor mechanisms that enabled defensive beha-
vior). Though some of the resulting mechanisms are genetically
hardwired (like more primitive creatures we automatically
scratch what itches and spit out what tastes foul), some also
permit “calibration” (sect. 7.4) or learning. Rituals arise during
this learning process, specifically when the hazard repertoire is
queued by an implicit hazard (one not consciously recognized
as a hazard) even when the precaution repertoire contains
nothing to adequately deal with it. This B&L denote, cleverly
and plausibly, as an instance of capture. Capture is the Achilles’
heel of our Precaution System. Because “any system of this kind
is vulnerable to capture” (sect. 8.3), we hardly need be surprised
by the ubiquity of religion or by the existence of OCD. Thus, the
explanatory dividends begin to roll in.
Indeed, I would argue that the scope of this explanation is even
broader than B&L claim. Given that learned responses to
implicit hazards are included, science itself (or at least the scien-
tific urge) is explained. Scientific method is our ritualized
response to the implicit hazard of ignorance.
In religion there is at least the possibility that ritualized
behavior may silence the queuing mechanism: through a reli-
gious ritual one might, for instance, expiate one’s guilt before
God (implicit hazard). But implicit hazards, being not con-
sciously present (by definition?), may persist despite the ritual.
The implicit queuing of the OCD sufferer’s uncleanliness detec-
tion system might persist despite hand washing – permitting
temporary relief only when attending to the washing itself (goal
demotion, sects. 6.2–6.4): a formula for obsession if ever there
was one, and a lovely explanation of OCD. Bravo! But note
well that nothing prevents such pathology in religion: adherents
who cannot shake off the implicit hazard of guilt may tirelessly
repeat religious rituals to get momentary relief.
Running through B&L’s account is an implicit (even uncon-
scious?) distinction between the pathological and the healthy.
Is it because the explanation of religious ritual as pathology is
so implicitly hazardous that B&L ritually back away, protesting
that there is more to cultural ritual than ritual behavior “writ
large”? They point out that religion involves social organization –
but isn’t that an accidental difference? How hard is it to imagine
an OCD religion based on the ideal of cleanliness and prescribing
obsessive rituals to fend off the relentless uncleanliness of this
world?
Darwin, too, hesitated to offend religious sensibilities. No
wonder B&L don’t even mention a more dangerous idea:
science, too, is a ritual. Note well that it is at least capable of sus-
taining pathology – we needn’t mention the arms race or
eugenics to see that this is so. Scientific ritual may also be
healthy, just as the normal ritual of washing before meals is
healthy, only science defends us not from uncleanliness, but
from ignorance – and this is a very good thing.
Multicultural religious and spiritual rituals:
Meaning and praxis
Joan H. Hageman
PsyMore Research Institute, Inc., Tampa, FL 33694.
psymore@verizon.net
Abstract: This commentary argues against the theory that cultural ritual
behavior is meaningless or that ritual action is solely a by-product of fear-
based precautionary and action-parsing systems. Humans demonstrate
the ability to spontaneously change their use of proximate intentions
and attribute ultimate intentions to ritual actions that are not
dependent upon fear or physical and emotional/mental dysfunction.
Boyer & Lienard (B&L) theorize that ritual is not rationally
based, and is an attempt to attain relief from anxiety-based cog-
nitive intrusions. They base their theory on a premise, stemming
from obsessive pathology etiology, security motivation theories,
and neuro-cognitive adaptive functions, that ritualized actions
emerged from an evolutionary fear-based system that acts to
protect the human from inferred threats to fitness. They
propose that ritual actions are a by-product of precaution and
action-parsing systems.
The authors’ stance is reminiscent of Freud’s widely accepted
idea (Strachey 1976) that adherence to a Western religious prac-
tice is a neurotic excursion as “wishing thinking,” in that individ-
uals feel the need: for protection from untamed nature, to
reconcile with the privations of social life, and to fulfill longing
for the lost father figure. Philosophically, these assumptions
surface from the earlier biomedical and current psychobiomedi-
cal model in which the “interiors of the human” (e.g., perception,
beliefs) are now recognized as having at least a semi-causal role in
health. However, neither model allows for the possibility of Car-
tesian duality, which has been rejected by Western science for
some time. Nonetheless, duality is central to most religious
and/or spiritual rituals.
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This raises an ethical issue regarding the arbitrary imposition
of Western ideology upon non-Western belief systems and prac-
tice, in addition to the likely misunderstanding of the non-
Western religious and/or spiritual practice. This imposition
also restricts a delineation of the meaning and teleology of the
rituals employed. Thus, the understanding of ritual becomes con-
strained by the attempt to reduce ritual to neurological events
originating from a built-in “self-protection” system. It severely
limits a comprehension of multicultural rituals that typically
involve varied aspects of duality.
Understandably, the neurological mechanisms that allow for
ritual behaviors are very important in the clarification of a
body-mind interaction, and the potential for the human to self-
heal among other benefits. However, the fact that the neurologi-
cal mechanisms may exist does not explain why they emerged, or
their role in how individuals perceive awe or agency, whether or
not during ritual. In fact, it is reasonable to argue that ritual beha-
vior could not occur if the neurological mechanisms were absent.
The assumption that ritual stems from a fear-based multifunc-
tional neurological system is limiting. It is more plausible to argue
that both fear and pleasure (e.g., joy, awe) are likely motivators in
the occurrence of ritual. Although it is important to understand
ritual independent of esoteric foundations, the understanding
of specific ritual teleology that incorporates some concept of
duality is equally important in the delineation of a body-mind-
spirit (e.g., agency) interaction, especially when both ritual prac-
tice and beliefs are involved in examining health outcomes
(Hageman 2002, 2005).
In support of the idea that ritual reduces anxiety, ritual is fre-
quently employed when physical and emotional/mental health
issues impact self-identity, the relationship to others, and the
relationship to the transcendent (May 1991, p. 9–12). In ritual
and ritual-like activities, liminal experiences engage the sympath-
etic and parasympathetic subsystems that alternatively arouse or
quiet subcortical neural processing and hormonal involvement
(Hogue 2006, p. 231), which may result in emotional engagement
as well.
As an alternative to an “inferred threat-based” theory, it may
be argued that neural mechanisms provide a “container” in
which emotional memories can be encoded, retrieved, rehearsed,
and re-encoded for spiritual formation and transformation
(Hogue 2006, p. 231). D’Aquili and Newberg (1999,
p. 112–16) provide support to this idea in that neural changes
produce a self-reported lack of self-boundaries in the brains of
experienced meditators. R. J. Davidson and colleagues
(J. M. Davidson 1976; R. J. Davidson 2000, 2004; Davidson
et al. 2003) offer support by showing that brain neuroplasicity
and affective style may be significantly affected by meditation.
All of these supportive arguments suggest that individual or
group ritual and religious experiences, such as mystical states
(D’Aquili & Newberg 1993), may result in similar experiences.
Moreover, gesture, movement, posture, and state of arousal
have a “bottom-up” effect on participants’ experiences in which
movement and gesture make use of the somatic subcortical
experiences that deepen the experience of self (Hogue 2006,
p. 237). However, affect or awe is not always fear-based.
Although ritual lacks a precise definition (Bell 1997, pp. xi,
253), ritual activities do have meaning and contribute to the con-
tinuity and the transformation of the personal and of commu-
nities (Hogue 2006, p. 230). It appears that less frequently
performed rituals may require higher levels of pageantry in
order to encode the details and significance of specific rituals.
Participation in ritual strengthens their reliability, whereas the
narrative construction of specific rituals unfolding over repeated
instances serves to establish the extent of a ritual’s meaningful
impact. Others have suggested that the impact of specific
rituals is largely determined by the initial heightened alertness
during the ritual and the subsequent on-going vindication of
the experience (e.g., cognitive alarm hypothesis proposed by
McCauley & Lawson 2002, p. 78).
It is quite apparent that humans have the ability to spon-
taneously change their use of proximate intentions and attribute
ultimate intentions to ritual actions that are not dependent upon
physical or emotional/mental dysfunction. Rituals appear to act
with intention to organize and orient individuals to act on the
lived-in world (Handelman 1998; Sørensen 2005). In this
regard, social factors may explain the form and content of ritual
action. Evolutionary or neurological theories (e.g., precaution
systems, mirror neurons) may explain how emotion and specific
actions interplay in dysfunctional repetitive behavior, or in
experiencing benefits while observing or participating in ritual.
Cognitive theories may elucidate the concept of agency in reli-
gious ritual. These theories only partially demarcate why ritual
emerged, and why it is a consistent phenomenon in normal
human behavior.
In conclusion, a theory of ritual, as noted by Gerholm (1988,
p. 197), should explain the effects of ritual, how ritual works in
its own terms in ways that may not be recognized by indigenous
theory (i.e., the embedded deeper beliefs of a particular culture’s
traditional practice of “being-in-the-world” that is defined during
a specific time of the culture’s history, which includes the esoteric
explanations for how the ritual works), and illuminate the pro-
duction of ritual effects in unknown and unanticipated ways. A
theory of ritual behavior predicated upon the assumption that
rituals lack meaning (e.g., Staal 1979) and a neurological expla-
nation of inferred threat does not fully explicate normal ritual
behavior.
What is the relevance of Boyer & Lienard’s
model for psychosocial treatments?
Jonathan D. Huppert and Shawn P. Cahill
University of Pennsylvania School of Medicine, Center for the Treatment and
Study of Anxiety, University of Pennsylvania, Philadelphia, PA 19104.
huppert@mail.med.upenn.edu scahill@mail.med.upenn.edu
http://www.med.upenn.edu/ctsa/
Abstract: Boyer & Lienard’s (B&L’s) model of obsessive-compulsive
disorder (OCD) rituals does not completely conform to our clinical
experience with patients, and the clinical implications of their model is
not described by the authors. We discuss potential differences of
opinion regarding both the nature of OCD and the mechanisms
involved in the maintenance of symptoms, and how emotional
processing theories can account for treatment effects.
The authors present an interesting attempt to account for
ritualized behaviors across a series of domains, including obses-
sive-compulsive disorder (OCD), from evolutionary, neuro-
physiological, cognitive, and anthropological perspectives. We
are clinical researchers and experimental psychopathologists
who focus on the nature and treatment of anxiety disorders
including OCD. This viewpoint is one of the most underdeve-
loped features of the model presented by Boyer & Lienard
(B&L), evidenced by the devotion of a single sentence to the
issue of treatment (sect. 7.3). In their attempt to understand
repetitive behaviors as disparate as children’s ritualized actions,
cultural rituals, and OCD, the authors contend that certain
aspects of all rituals are similar enough to merit a common expla-
nation. By contrast, as diagnosticians, clinicians, and psycho-
pathologists our goal is to understand these behaviors in order
to help patients eliminate them and improve functioning and
quality of life. Specifically, we are interested in the question,
“How do compulsions differ from apparently similar behaviors?”
One of the basic distinctions between OCD rituals and cultural
rituals are in the functions served by the behaviors, and therefore
in the goals one has in affecting them. Compulsions are triggered
by obsessions, maintain anxiety, and need to be reduced in order
to improve quality of life. Cultural rituals, by contrast, are often
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adaptive behaviors promoted within society, assisting communal
coherence.
Overall, there are some issues raised by B&L that do not
reflect our knowledge of OCD. In fact, the psychosocial treat-
ment of choice for OCD includes exposure and response preven-
tion, which was derived from cognitive and behavioral theories
that do not describe the necessary features of B&L’s model
(Franklin & Foa 2002).
Many of our differences of opinion lie in their characterization
of the features of OCD. Although many fears (OCD obsessions
being no exception) have a level of preparedness (Seligman
1971), it seems that the OCD can take on modern concepts as
well as capturing evolutionarily based threats. For example,
fears of sin and damnation, as well as rituals such as checking
stoves, light switches, appliances are common issues in OCD
(Foa et al. 1995). In addition, the concept of inferred danger
characterizes most anxiety disorders, whereas rituals are more
exclusive to OCD. Thus, it is not clear from the model why indi-
viduals with other anxiety disorders do not typically engage in
rituals. Furthermore, other cognitive characteristics, such as
thought-action fusion and hyper-responsibility, may be more
unique to OCD (Rachman 1993) than other anxiety disorders,
but the model does not clearly account for such important
features.
Rituals are not always conducted in a repeated, systematically
rigid fashion. While caricatures of patients with OCD portray
individuals engaging in explicit, repeated behaviors, the clinical
picture is much more complex. Individuals with OCD often
have varied responses to adapt to a situation. Thus, individuals
who typically use tissues as a barrier to avoid contamination
when opening doors may instead allow others to open the door
or use a sleeve as a barrier when a tissue is not available. Alterna-
tively, they may seek reassurance from others, mentally review
reasons why they are not contaminated, or decide to delay
their ritual while taking measures to limit further spread of the
contaminant along with keeping track of which body parts or per-
sonal items will later need to be cleaned. Patients can be extre-
mely creative in working to obtain relief from anxiety through
subtle reassurance seeking or other means. Our clinical experi-
ence is that patients with OCD are in fact quite flexible with
their utilization of rituals, and elimination of all of the potential
responses is a key to treatment.
The idea that rituals necessitate action parsing, goal demotion,
and swamping of working memory also does not reflect our clini-
cal experience. Contrary to B&L’s suggestion, patients are often
unaware of some of their rituals precisely because they have
become so habitual. Ritual monitoring is the first stage of treat-
ment, and many patients state that the process of recording
their rituals makes them more aware of the rituals in which
they are engaged. For example, a recent patient whose rituals
involved repeatedly saying “I am sorry” reported being quite sur-
prised by the high frequency with which she was offering
unnecessary apologies. Patients also frequently report engaging
in rituals prior to being aware that they are doing them. Further-
more, many OCD patients appear to be quite clear about their
goals and do not lose sight of those goals as they begin to ritualize.
Indeed, they frequently view their rituals as direct attempts to
achieve their goals. Even when action parsing occurs, the ulti-
mate goal of removing danger usually remains very much at the
forefront of their thoughts.
We contend that overt rituals are best understood as a part of a
larger class of avoidance behaviors seen in OCD, along with
mental rituals, overt avoidance, and other emotion regulation
strategies such as thought suppression. All of these behaviors
and mental manipulations promote immediate relief of anxiety
but serve to maintain fear and obsessions over the long run
(Franklin & Foa 2002). The psychosocial treatment of choice
for OCD is the combination of exposure situations and thoughts
that elicit obsession-related anxiety and response prevention of
the various avoidance behaviors, both of which are important
components to treatment (cf. Foa et al. 1980). However,
B&L omit the importance of exposure for treatment, and the
mechanisms through which exposure is thought to work (Foa
et al. 2006). Our view is that OCD, and other anxiety disorders,
reflect the operation of a fear network which consists of patho-
logical associations between neutral stimuli and representations
of danger along with physiological, cognitive, and behavioral
responses associated with fear (e.g., avoidance behaviors).
Psychological treatment requires activation of the fear network
and exposure to disconfirming information. In vivo exposure
and imaginal exposure activate the fear network and the non-
occurrence of feared consequences provides the disconfirming
information. Rituals serve to reduce that activation through the
inaccurate belief that the danger has been removed or elimi-
nated, thereby maintaining anxiety. For example, a patient touch-
ing a doorknob without washing leads to learning that they did
not get a disease and that relief occurred without ritualizing.
The model offered by B&L seems to miss the importance of
obsessions and the functional nature of compulsions in des-
cribing OCD. Consideration of the rich database on the psycho-
logical treatment of OCD serves to inform and constrain theories
of OCD.
Ritualized behavior in sport
Robin C. Jackson and Rich S. W. Masters
Institute of Hum an Performance, The University of Hong Kong, Hong Kong,
SAR, China.
robjacks@hku.hk mastersr@hku.hk
Abstract: We consider evidence for ritualized behavior in the sporting
domain, noting that such behavior appears commonplace both before a
competitive encounter and as part of pre-performance routines. The
specific times when ritualized behaviors are displayed support the
supposition that they provide temporary relief from pre-competition
anxiety and act as thought suppressors in the moments preceding skill
execution.
One domain in which a colorful raft of ritualized behaviors can be
seen is sport. Superstitious behaviors are extremely common
(Neil 1982) and many can be characterized as stereotyped,
rigid, repetitive rituals, lacking in rational motivation. Performers
may feel compelled to “gear up” in a particular order, to tie and
retie their bootlaces, or to perform the same pattern of behavior
each time they run onto the field of play.
Boyer & Lienard (B&L) explicitly contrast ritualized behavior
with commonsense notions of rituals as actions that are per-
formed routinely or without thinking. Ritualized behaviors are
“recognizable by their stereotypy, rigidity, repetition, and appar-
ent lack of rational motivation” (target article, sect. 1, para. 1),
whereas routine actions are performed without thinking but
with motivation. A defining feature of ritualized acts is that
they do not seem to become automatic and remain subject to
high-level cognitive control. B&L further note that ritualized
acts in obsessive-compulsive disorder may swamp working
memory and appear to result in a temporary reprieve from
what may be extremely debilitating state anxiety.
In sport, the outcome of a competitive event – and with it the
achievement of a status for which the performer will typically
have invested many years and many thousands of hours of prac-
tice – often comes down to executing a skill successfully at a
given moment. The resulting pressure leads many performers
to “choke,” or perform well below the level of which they are
capable. There is considerable evidence that skill failure results
from performers focusing on low-level units of behavior and, in
particular, from attempting to exert conscious control over
actions that normally “run off” automatically. Much evidence
for this conscious processing hypothesis (Liao & Masters 2002;
Masters 1992; Maxwell et al. 2003) has emanated from skills in
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which the performer has time to think prior to executing the
skill (e.g., golf putting), but there is also evidence from reactive
skills, such as baseball batting (Gray 2004). It may even be the
case that conscious processing of one’s movements, described
by Masters et al. (1993) as “reinvestment,” is potentially a
mode of ritualistic intrusive thought that, hypothetically, may
eventually mutate to become obsessive compulsive. Golfers
with type II “yips,” for example, are highly compulsive and
analytical (Smith et al. 2003), and “what should be an automatic
unified movement, becomes a complicated problem of con-
sciously coordinating many separate movements” (Cochran &
Stubbs 1968, p. 135).
One of the predictions generated by B&L’s account is that
ritualized behavior may be functional insofar as the temporary
swamping of working memory prevents performers from “rein-
vesting” conscious control (Masters et al. 1993), as well as result-
ing in a temporary reduction in anxiety. Ritualized behaviors
should be evident in abundance in the period immediately pre-
ceding a competitive encounter, as performers attempt to gain
control of their emotions. They should also be present as “mod-
erately efficient forms of thought-suppression” (target article,
sect. 7.2, para. 2; emphasis in original) in the moments immedi-
ately before skill execution, particularly in self-paced skills.
Consistent with these predictions, many performers do appear
to engage in ritualistic behaviors before a competitive event
(Neil 1982) and often include ritualistic elements in pre-perform-
ance routines (Foster et al. 2005).
There are also many examples of performers displaying
ritualized behavior during breaks in competition. In tennis,
Raphael Nadal takes great care to position and align his fluid
replacement bottles at each change of ends, after drinking
from both. Another top player, Justine Henin-Hardenne, reput-
edly avoids stepping on the lines on the court between points.
While behavioral aspects of pre-performance routines, such as
their timing, appear to be controlled at a sub-conscious level
(Jackson 2003), performers often include conscious elements
that may suppress conscious control processes. For example,
Foster et al. (2005) showed, in a study of superstitious behavior
in basketball free-throws, that some of the behaviors players
felt compelled to perform included tapping their head three
times before shooting, and touching their heels alternately
before each throw.
As well as displaying the characteristics of compulsion and
rigidity, other activities also appear consistent with the concept
of goal demotion. A golfer clearly needs to grip the club correctly
but when the player ritually re-grips the club a set number of
times, the behavior becomes divorced from the observable
goal. Indeed, this type of behavior sometimes appears similar
to that of obsessive-compulsive “checkers.” Golfers may be
aware that re-gripping the club over and over is unnecessary
but feel they have little control over their behavior. Similarly,
while it would appear eminently sensible to look at the golf ball
when preparing to putt, focusing intently on each letter of the
manufacturer’s name is not a necessity, though it may well be
an effective way to suppress anxiety provoking or performance
disruptive thoughts. Indeed, B&L suggest that patients may
intuitively produce behaviors that reduce anxiety, and Neil
(1982) has argued that superstitious behavior provides a means
by which performers can cope with the stress of competition
under pressure.
Although much of the evidence is anecdotal, there appear to
be many examples of ritualized behavior in sport that are consist-
ent with B&L’s account. Sporting competition heightens anxiety,
and skill failure often results from attempting to consciously
control actions. Pre-competition ritualized behaviors may
provide temporary relief from heightened anxiety while ritua-
lized elements of pre-performance routines may help prevent
the performer from “reinvesting” conscious control of the skill
itself, a process that is implicated in “choking” or skill failure
under pressure.
Spectrum of child psychiatric disorders and
ritualized behavior: Where is the link?
Roumen Kirov
Laboratory of Cognitive Neurodynamics, Institute of Physiology, Bulgarian
Academy of Sciences, 1113 Sofia, Bulgaria.
ru@bio.bas.bg http://www.bio.bas.bg
Abstract: There is a spectrum of child psychiatric and neurological
disorders, in all of which a comorbidity with obsessive-compulsive
disorder and ritualized behavior is very common. Therefore, they may
appear as a basis for the rituals in children that cross into adolescence
and adulthood. Resolving the nature of these disorders may help us to
better understand “Why ritualized behavior?”
The model proposed by Boyer & Lienard (B&L) is essential in
several respects. First, in that it takes into consideration an
extended data base by engaging diverse domains of ritualization.
Combining evidence from different fields of science, B&L
suggest that a unitary “evolved Precaution System” is responsible
for ritualized behavior, in particular in obsessive-compulsive dis-
order (OCD). Second, the authors’ efforts to conceptualize and
model the neural basis of ritualized behavior should be appreciated;
their model can certainly enhance the understanding of this aspect
of human behavior in both normal and pathological conditions.
What deserves particular attention from fundamental and
clinical points of view, and may require further refinement, are
the neural mechanisms responsible for the evolved Precaution
System suggested by B&L. As emphasized by the authors,
OCD is likely to underlie the pathophysiological mechanisms
leading to deficits of that system in both children and adults. In
this regard, it is of special interest that there is a spectrum of
child psychiatric and neurological disorders such as attention
deficit/hyperactivity disorder (ADHD), tic disorder (TD) and/
or Tourette syndrome (TS), oppositional-defiant disorder
(ODD), pervasive developmental disorder (PDD), nocturnal
enuresis, learning disability, separation anxiety, and depression,
in all of which co-morbidity with OCD is very common
(Banaschewski et al. 2003; Becker et al. 2003; Biederman &
Faraone 2005; Biederman et al. 1992; Geller 2006; Geller et al.
2004; Hounie et al. 2004; Leckman 2002; Leckman et al. 1997;
Lewin et al. 2005; Masi et al. 2004; Nestadt et al. 2001; Peterson
et al. 2001; Rothenberger & Banaschewski 2006; Rothenberger
et al. 2000; Swanson et al. 1998; Yuen et al. 2005). Ritualized
behavior is also frequently observed in girls with anorexia and
abulia neurosa (Kaye et al. 2004; Sodersten & Bergh 2006;
Yohanan et al. 2006).
Therefore, a broad continuum of child psychiatric disorders
appears associated with rituals that may further cross into adoles-
cence and adulthood. However, although still under research, the
neurochemical and neurophysiological mechanisms of particular
disorders are recognized to differ substantially. Various studies
have provided converging evidence that the neuronal substrate
underpinning ADHD is the dopamine deficit in the meso-
limbic and meso-cortical circuits, with the norepinephrine
system also being involved (Biederman & Faraone 2005;
Castellanos & Tannock 2002; Sagvolden et al. 2005; Swanson
et al. 1998). In contrast, tic disorder (TD, TS) is supposed to orig-
inate from an enhanced dopaminergic neurotransmission and a
hypersensibility of dopamine receptors in the striatum
(Leckman 2002; Leckman et al. 1997). Motor system excitability
also differs in these two disorders (ADHD and TD). The appli-
cation of transcranial magnetic stimulation has revealed a
reduced intracortical inhibition in children with ADHD (Moll
et al. 2000), whereas a deficient inhibition of sensorimotor
cortico-subcortical circuits is found in children with TD
(Zieman et al. 1997). In this line, although not definitely known,
dissimilar pathophysiological mechanisms seem to be activated
in ODD, PDD, nocturnal enuresis, learning disability, anorexia
nervosa, and separation anxiety, all combined with ritualized
behavior. In addition, a serotoninergic deficit has been shown
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in depression (Charney et al. 1981; Levinson 2005; Walitza et al.
2002) and selective serotoninergic reuptake blockers are gener-
ally recommended for the therapy of OCD and ritualized beha-
vior (Blier et al. 2006; Pediatric OCD Treatment Team, 2004).
Taken together, such results imply that the mechanisms of the
ritualized behavior can be linked with or facilitated (or even trig-
gered) by very different neural pathogenic sources, meaning that
these mechanisms may be more complex than B&L suppose.
Hence, there are two major open questions. First, what are the
neuropathological mechanisms of the ritualized behavior that
may be common in all these child psychiatric entities; and
second, whether and to what extent a genetic polymorphism
plays a role (Castellanos & Tannock 2002; Leckman 2002;
Rothenberger & Banaschewski 2006).
B&L further propose that cognition plays a role in ritualized
behavior. In this respect, it is very important to note that the
role for sleep in learning and memory is generally recognized.
Hence, it would be of great interest to discuss the possible role
of sleep in ritualized behavior. It is generally accepted that
stage 2 of non-rapid eye movement (non-REM) sleep is associ-
ated with declarative memory consolidation, whereas REM
sleep is supposed to play a role in procedural memory (Gais
et al. 2006; Hobson 2005; Stickgold 2005; Stickgold & Walker
2005). This issue raises at least two questions: (1) whether ritua-
lized behavior occurs in relation to sleep, and, if so, (2) which
sleep stage consolidates it. Consequently, sleep research in chil-
dren, adolescents, and adults who have OCD and/or ritualized
behavior merits attention.
ACKNOWLEDGMENTS
The preparation of this commentary was supported by DFG, Germany
(436-BUL-112/35) and National Council for Scientific Research,
Bulgaria (L-1316).
How far will an account of ritualized behavior
go in explaining cultural rituals?
Robert N. McCauley
Department of Philosophy, Emory University, Atlanta, GA 30322.
philrnm@emory.edu
http://userwww.service.emory.edu/ philrnm/
Abstract: The theory of ritualized behavior should offer insight about
cultural rituals. Considering ritualized behaviors’ scripted actions and
both the frequent absence of anxiety and the routinization of many
cultural rituals, questions remain about how much and what precisely
gets explained. Among religious rituals, ritualized behaviors arise more
strikingly in special agent rituals, but that might be because they
usually include novices.
The dogma that ritual will submit to a unified theoretical treat-
ment has burdened cultural anthropology for decades. Attending
to the psychological foundations of cultural rituals, Boyer &
Lienard (B&L) join myself and Lawson (Lawson & McCauley
1990; McCauley & Lawson 2002) in questioning that presump-
tion. B&L maintain that rituals do not constitute a natural kind
but that individuals’ “ritualized behaviors” are elements in
many (individual and collective) cultural rituals, which other
behaviors of individuals – including the rituals of obsessive-
compulsives, of children, and of normal adults at pivotal points
in their lives – exhibit as well. All such manifestations of ritua-
lized behavior enlist dispositions of the human mind to (1)
attend to potential hazards that were characteristic of ancestral
environments, and (2) undertake associated precautions in
response. B&L develop Boyer’s (2001b) contention that cultural
rituals persist because they exploit these mental dispositions.
Successful cultural rituals approximate a sufficient number of
cues associated with items in the “Potential Hazard Repertoire”
well enough to activate, if not engage, the programs connected
with corresponding items in the “Hazard-Precaution Reper-
toire.” They “cognitively capture” domain specific processing
principles that elicit a narrow range of comparatively regularized
motor (and affective) outputs such as hand washing.
B&L grant that ritualized behaviors are “not the whole of [cul-
tural] ‘rituals’” (sect. 8.6, para. 2). They also reject the view that
differences between cultural rituals and other points on the spec-
trum of ritualized behavior that they envision are simply ones of
degree, as they spurn the Freudian notion that cultural rituals are
a “scaled” up version of individuals’ ritualized behaviors. Still,
they hold that their proposal should explain (a) why cultural
rituals are widespread and compelling, (b) why they so often
incorporate particular themes, and (c) “why these common
endeavors should include scripted, goal-demoted, redundant
scripting of familiar actions” (sect. 9.1, para. 2). Questions
remain, however, concerning just how much and what precisely
about cultural rituals B&L’s account of ritualized behavior
explains. Following are some considerations that may pertain to
sorting those questions out.
B&L argue that cultural rituals seem compelling to partici-
pants because they cognitively capture the machinery of the
potential-hazard detection and precaution systems. At least
sometimes, though, the compulsion to perform cultural rituals
that play on these themes is tepid at best, and the prospect of
facing the consequences of failing to perform them provokes
little, if any, anxiety. The opening ceremonies of the Olympic
Games, the lighting of the torch, the athletes’ recitation of the
Olympic oath, and the head-of-state’s public declaration of the
Games’ beginning, no doubt create considerable excitement
and inspiration; but few would feel much anxiety about the
ensuing two weeks of competition if these events were rained
out, or many athletes were too distracted with taking pictures
of the events to take the oath, or the head-of-state’s inebriation
led to an unrecognizable declaration. Why, as B&L concede, is
the compulsion accompanying cultural rituals, which co-opt the
forms of ritualized behavior, often so thin, and how do they
manage to dispel the anxiety that should result concerning the
possibility of non-performance?
B&L discuss both logical and psychological aspects of goal-
demotion in cultural rituals. Patterns of actions such as reversals
and repetitions undermine those actions’ instrumental coher-
ence, whereas a focus on low level parsing of ritual actions
results in participants’ inattention to either sub-goals or overall
goals (at least in the course of carrying out the actions in ques-
tion). This occasions two comments. First, the duration of any
inattention to goals differs considerably from one ritual and
one context to the next. On B&L’s theory, ritualized behavior
includes comparatively rigid adherance to a script. For
example, in the aforementioned item (c), they twice describe
these actions in terms of scripts, and scripts are typically charac-
terized in terms of goals. Among the non-literate mountain Ok of
New Guinea (Barth 1987), the script and its goal – not just what
people happen to remember – determine what matters enough
to get included in the “remembered pattern.”
Second, B&L contend that goal-demotion prevents ritualized
behaviors from becoming automatic or routinized and insist
that this feature is “essential” to their account of the role of ritua-
lized behaviors in cultural rituals. Perhaps so, but that does not
discredit the commonsense view that cultural rituals often
involve mindless routine. Addressing this matter, B&L speak of
cultural rituals as “ceremonies,” which alternate between non-
automatic ritualized behaviors and routinized, automatic
actions. The proportion and prominence that B&L’s ritualized
behaviors enjoy, at least in religious rituals, can vary vastly. The
frequency with which the Pomio Kivung repeat all of their
rituals has guaranteed that those rituals have become thoroughly
routinized even for the least involved participants (Whitehouse
1995). Participants find these familiar rituals so boring that
they sometimes fall asleep during their performance. Even in
religious ritual systems that include key rituals in which ritualized
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behaviors have a more salient role, at least some priests, in con-
trast to ritual novices, give every evidence of proceeding through
utterly familiar routines automatically. Ritualized behaviors seem
to arise more strikingly, if not more regularly, in what Lawson
and I (see McCauley & Lawson 2002) have dubbed “special
agent rituals,” that is, religious rituals in which agents with
counter-intuitive properties (or their ritually designated repre-
sentatives) do things to participants that bring about permanent
changes in those participants’ religious and ritual statuses.
The crucial point is that these are rituals that participants typi-
cally undergo only once in their lifetimes, so all of the patients of
these rituals are novices. (The most obvious but by no means sole
illustrations are the classic rites of passage.) Since these novices
may be comparatively unfamiliar with these rites or the rites
may simply be so elaborate, in many cases (e.g., bar mitzvahs)
they go through preparations for these ceremonies that can
readily result in actions that display the characteristic earmarks
of ritualized behaviors including goal-demotion and swamped
working memory. Moreover, the publicity of these rituals and
the representations religious systems deploy seem to foreclose
on any pathologies analogous to OCD. The gods seemed to
have mastered the trick of allaying the concomitant anxieties,
since what the gods do, they need do only once.
Ritual pathology and the nature of ritual
culture
Bjorn Merker
Gamla Kyrkv 44, SE-14171 Segeltorp, Sweden.
gyr694c@tninet.se
Abstract: Boyer & Lienard’s (B&L’s) biological model of ritual achieves a
rather straightforward account of features shared by ritual pathology and
the idiosyncratic rituals of children; but complexities accrue in extending
it to human ritual culture generally. My commentary suggests that the
ritual cultural traditions of animals such as songbirds share structural
features, handicap-based origin, as well as the enabling neural
mechanism of vocal learning with human ritual culture.
Boyer & Lienard (B&L) draw a number of convincing parallels
between the phenomenology of ritual pathology and the idiosyn-
cratic rituals developed by young children without apparent
pathology. The family resemblance between the two domains is
a strong point of their perspective, and supports the reality of
the hazard-precaution system they outline for us. But what of
the delightful handclapping and similar rituals of children at
play? These complex, scripted, stereotypic, repetitive, and inter-
active play rituals can be found in diverse cultures around the
world, but go unmentioned by B&L (Opie & Opie [1960]
provide a striking sample from England). The ambience of
merriment and camaraderie that sustains play rituals lies far
from the negative emotions on which B&L’s model turns. More-
over, sequences in play rituals are not idiosyncratic but are
shared by the local or regional playground culture – though
they differ across regions and cultures. The actions these
sequences involve need in no way echo precautionary measures
(e.g., mutual touching of hands without a hint of “washing”);
they are not usually invented by participants but are acquired
by a learning process involving coaching by peers and deliberate
practice in conformity with a local prototype, which, like other
cultural traditions, shows continuity as well as change across gen-
erations; and they typically feature vocal activity in the form of
chanting, rhyming, singing, or recitation. In all these respects
the play rituals of children are perfect miniatures of the normal
human cultural rituals which cause B&L so much difficulty in
the concluding sections of their article.
The reason for the difficulties, I suggest, is that normal human
cultural ritual has a source other than the one suggested by B&L.
The key to its identification is the very “waste of time and
resources” that makes it so tempting to assimilate cultural ritual
to ritual pathology, but which in the light of modern behavioral
biology hints at another source. The point of the elaborateness,
conspicuousness, and persistent repetition (often with variations)
of animal ritual displays (which may require lengthy learning and
practice for proficiency, as in birdsong) is the very waste of
resources such attributes entail. This makes them “costly” and
qualifies them as fitness indicators on the simple principle that
whoever can sustain such waste on a regular basis commands
resources over and above those required for merely “getting
by,” and thus is worth taking seriously. Contrary to B&L (sect.
9.2), these signals are never directly related to the fitness dimen-
sion they advertise. They function as proxies or substitutes for
direct tests of fitness according to the handicap principle
(Zahavi & Zahavi 1997). The length to which such indirectness
can go is demonstrated by the awkwardly named “nutritional
stress hypothesis,” according to which the size of a songbird’s
repertoire, via brain size in turn dependent on early parental
care becomes an indicator of fitness reflected in reproductive
success of the adult singer (see Hasselquist et al. 1996; Nowicki
et al. 2002).
The handicap principle helps us understand the “goal-
demotion” which features so prominently in B&L’s account of
ritual, but remains unexplained there. Genuine cultural tra-
ditions among nonhuman animals (Fragaszy & Perry 2003)
come in two kinds: instrumental culture and ritual culture
(Merker 2005). The behaviors transmitted by an instrumental
tradition pay their way by being usefully arranged to accomplish
an invariant practical outcome (food washing, termite extraction,
and nettle stripping traditions are primate examples). Context-
attuned performance flexibility is the hallmark of instrumental
behavior, whereas literal duplication of the actual details
performed by an observational model is likely to impede rather
than promote instrumental success.
Literal duplication, however, lies at the very heart of ritual.
The need to remember and reproduce essentially arbitrary
details on an obligatory basis burdens behavior with a handicap,
and the ability to sustain that burden is proof of capacity, and
hence tends to impress. Formally, ritual is identifiable by the
fact that a hypothetical pattern substitution – such as a sequence
reversal or inversion – does not on those grounds alone allow one
to conclude that the altered sequence in principle is any less fit
for its ritual purpose qua ritual than the canonical version, yet
performing the altered version counts as ritual error (Merker
2005). The pattern substitution may even be canonical in a differ-
ent subpopulation of the same species (say, of songbirds), thus
proving its ritual adequacy. Ritual adheres to correct form,
while the achievement of an instrumental outcome – assuming
there is one – counts for little if ritual form is violated. Hence
the goal-demotion, even goal-independence (in instrumental
terms), that is intrinsic to ritual.
There is reason to believe that humans by nature are carriers of
ritual culture in the sense just defined. We, in contrast to chim-
panzees – indeed, alone among all the primates (Janik & Slater
1997; Snowdon & Elowson 1992) but like many songbirds and
the humpback whale – are in possession of a neural mechanism
that allows us to duplicate with our voice that which we have
heard with our ears. Most mammals, who excel at learning in
other respects, are incapable of doing so (see review by
Janik & Slater 1997); yet we humans do so with every song we
know how to sing and with every word we know how to pro-
nounce. Through the duplicative logic of this mechanism – tech-
nically termed vocal learning, and supported by a “conformal
motive” intrinsic to it (Merker 2005) – we are equipped with a
natural facility for forms of imitative learning that faithfully dupli-
cate their model to result in the lasting acquisition of formally
patterned behaviors as integral parts of cultural traditions with
ritual characteristics. It is the “watershed adaptation” of vocal
learning (Nottebohm 1976), I suggest, that holds the key to
what makes us – and not chimpanzees – a ritual species.
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Such a perspective helps us understand why ritual form marks
human culture not only in domains touched by precautionary
concerns, but in well nigh every area of human pursuit. Many a
prayer ritual certainly is directed at warding off potential
threat, while others are directed at the acquisition of positive
benefits such as wealth beyond the necessities of life (i.e., unas-
similable to a scarcity context). Innumerable human rituals,
moreover, have a frankly celebratory nature (naming rites, birth-
day ceremonies, and harvest rites – typically performed after
rather than before the harvest – are cases in point). Hope and
affirmation thus join fear in the emotional ambience of cultural
ritual. Note also that a statistical skew in the thematic distribution
of cultural rituals in a precautionary direction is easily accounted
for by the general psychological asymmetry adhering to loss
versus gain in human judgments, an asymmetry by no means con-
fined to ritual circumstances (Kahneman & Tversky 2000). Much
more could be said about the matters touched upon here (the
interested reader may consult Merker [2005] and Merker [in
press] for additional detail), but I conclude by thanking the
authors for providing the occasion for these reflections through
their interesting and timely article.
Useful distraction: Ritualized behavior as an
opportunity for recalibration
John L. Orrock
National Center for Ecological Analysis and Synthesis, University of California,
Santa Barbara, CA 93101.
orrock@nceas.ucsb.edu http://www.nceas.ucsb.edu/ orrock
Abstract: Responding to potential hazards is likely to require precaution-
related recalibration, the extensive integration of complex variables
related to inferred risk and fitness. By swamping working memory with
goal-demoted actions and focusing recalibration on the inferred threat,
ritualized behaviors may serve to increase the efficacy of precaution-
related recalibration. This benefit may be an important mechanism
maintaining non-pathological ritualized behavior.
In addition to the specific actions described in the Potential
Hazard and Precaution model, responding to potential
hazards is also likely to require the activation of specific cogni-
tive pathways for the timely, effective processing of complex,
hazard-related information and the updating of fitness-related
variables, that is, precaution-specific recalibration (Cosmides
& Tooby 2000). The swamping of working memory that
occurs during ritualized behavior may have the additional
advantage of effectively serving to free-up higher-level cognitive
processes that are responsible for integrating and interpreting
complex information (Dijksterhuis et al. 2006). Although
working memory is necessary for making effective decisions,
its role in decision-making is not absolute (Bechara 2004).
Thus, the goal-demoted actions characteristic of ritualized
behavior may represent useful distractions that create a cogni-
tive environment where higher-level cognitive routines may be
effectively freed from the yoke of working memory, facilitating
more effective integration and processing of disparate forms of
information.
By this view, ritualized behaviors have two consequences for
information processing: (1) ritualized behaviors focus back-
ground processing explicitly on the inferred threat from the
Potential Hazard Repertoire, and (2) ritualized behaviors
swamp working memory, serving to further increase the effec-
tiveness of precaution-related background processing. As a
result, an intrusion or compulsion that arises because of inferred
threats from the Potential Hazard Repertoire is also beneficial for
promoting recalibration. This predicts that, in addition to being
triggered by an inferred threat, ritualized behaviors might be
engaged once an information threshold is reached whereby
further computational effectiveness requires extensive
recalibration. This information can take any form related to
fitness – it could be information that modifies the likelihood of
successful mate acquisition, changes the nature of a social con-
tract, provides opportunities for resource acquisition, and so on.
As a result, regardless of the original context in which ritua-
lized behavior arose, it may serve the additional purpose of
improving the processing of complex information and sub-
sequently reinforcing ritualized behavior. For example, compul-
sive cleaning may have arisen primarily to restore symmetry and
reduce contamination, but it may also have the benefit of provid-
ing a time when recalibration occurs. Thus, when faced with situ-
ations requiring recalibration (e.g., failure to get a promotion that
you were sure you were going to get), some individuals engage in
ritualistic cleaning, regardless of whether or not their home is
actually dirty. Similarly, ritualized behavior promoting symmetry
in one’s environment, such as stacking and re-stacking poker
chips while in a heated game, may be useful as a way to access
cognitive routines for assessing complex probabilities relating
to whether or not to call an opponent’s bet.
Ritualized behavior is often associated with particular stages in
life or specific circumstances (e.g., during stressful events, risky
situations) when more efficient precaution-related background
processing may be particularly advantageous. For example, ritua-
lized behavior is often pronounced during early childhood and
pregnancy, stages that are associated with an onslaught of
diverse, fitness-related information and the need to make import-
ant choices. As development occurs and ritualized behavior
becomes more culturally specific, the same ritualized behavior
once enacted in response to a cue from the Potential Hazard
Repertoire may be enacted in response to a situation that
requires extensive recalibration. As the usefulness of situation-
specific recalibration increases due to age or social circumstance,
ritualized behaviors may be entirely motivated by the need for
recalibration. For example, elderly individuals may exhibit
greater ritualized behavior because they are more susceptible
to inferred threats (e.g., less likely to escape a predator or
survive a pathogen). However, such individuals might also
exhibit more frequent ritualized behavior because age-related
changes in social status, ability to acquire resources, or cognitive
ability may require more frequent extensive recalibration.
Although the authors suggest that early cultural rituals may
have parasitized ritualized actions, it is possible that the
changes in background processing promoted by ritualized beha-
viors also promoted their use in cultural rituals. This may be the
case because a tremendous amount of information is available
during cultural rituals which often has direct bearing on an indi-
vidual’s social status, resource acquisition, and reproductive
opportunities (Rappaport 1971). Assimilating and interpreting
this information may require intensive recalibration, and may
serve as an additional explanation for why goal-demoted, redun-
dant behaviors are employed in cultural rituals. During the per-
formance of a cultural ritual, the use of these strictly ritualized
behaviors is typically interspersed with goal-oriented, non-ritua-
lized components (e.g., a display performed by some members of
the group while others observe). Thus, cultural rituals contain
periods of explicit information gathering interspersed with
periods of focused, fitness-related background processing,
mediated by the use of ritualized behaviors.
Recalibration may also play a role in the pathology of obses-
sive-compulsive disorder (OCD) as outlined in Boyer &
Lienard’s (B&L’s) model. In the authors’ model, OCD may
occur when ritualized behaviors are triggered, but doubt exists
that the selected action from the Evolutionary Precaution Reper-
toire was properly executed. This situation creates a positive
feedback loop that encourages continued intrusions and compul-
sions characteristic of OCD. However, if elevated background
processing were part of the system, closure of the system might
also occur once recalibration was sufficient (e.g., the poker
player stops stacking and re-stacking his chips, not because
they are finally in order, but because recalibration has finished).
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As such, in some OCD patients, an impairment in some com-
ponent of recalibration may cause closure to be less frequent.
ACKNOWLEDGMENTS
Helpful comments from D. Pietraszewski greatly improved the
manuscript, as did comments from O. J. Reichman, E. Damschen, and
L. Cosmides. This work was conducted while the author was a
postdoctoral associate at the National Center for Ecological Analysis
and Synthesis, a Center funded by NSF (DEB-0072909), the
University of California, and the Santa Barbara campus.
Does meditation swamp working memory?
Ilkka Pyysia
¨
inen
Academy of Finland and Helsinki Collegium for Advanced Studies, University of
Helsinki, FIN-00014 Helsinki, Finland.
ilkka.pyysiainen@helsinki.fi www.mv.helsinki.fi/home/ipyysiai/
Abstract: Religionists often presuppose that “mysticism” aims at
somehow emptying the mind. In the light of evidence, however,
meditation seems rather to consist of ritualized action without an
explicit emphasis on subjective experience. Boyer & Lienard’s (B&L’s)
theory of ritualized action as “swamping” working memory thus might
help explain the effects of meditation without postulating experiential
goals the “mystics” obviously do not have.
Rituals of meditation exemplify cultural rituals such as the ones
Boyer & Lienard’s (B&L’s) hypothesis is meant to explain.
They are of particular interest here because in religious studies
meditation is a paradigmatic example of an activity that aims at
emptying the mind (see Almond 1982; Andresen & Forman
2000; Tart 1969).
Scholars of meditation and mysticism are roughly divided into
two camps. “Perennialists” (see Huxley 1946/1959) argue that
meditation aims at a “mystical” experience that is everywhere
the same, irrespective of culture and tradition (Forman 1990;
1993; Stace 1960). “Constructivists” argue that all experience is
culturally constructed and that there thus is no pure experience,
apart from its conceptualization (Gimello 1983; Katz 1983; 1985;
Proudfoot 1985).
Many authors also make a distinction between introvertive and
extrovertive “mysticism.” The basic idea is that one can strive for
an experience of unity either by focusing attention on some exter-
nal object, or by “diving inwards” as it were (Almond 1982;
Pahnke & Richards 1969; Stace 1960). RobertQ1 Forman (1990,
1993) argues that the “pure consciousness” that Stace regards
as the outcome of the introvertive way, is a state in which one
is conscious, although one’s consciousness is not directed
towards any object and thus does not have any content.
In the light of neuroscience, it is more probable that what is
known as “pure consciousness event” is an unconscious but
wakeful state (Pyysia
¨
inen 2001, p. 114). One cannot, however,
use contemporary practices as “transparent windows to the
past” in trying to find or reconstruct a timeless “mystical” experi-
ence (Sharf 1995, p. 235). Sharf has amply shown that the wide-
spread idea of Eastern religions as laying a heavy emphasis on
subjective, “mystical” experience is an unfounded Western pro-
jection (Sharf 1995; 1998).
Whether it is Theravada Buddhism, Tantrism, or Zen, histori-
cal and ethnographic reports clearly show that the emphasis is
nearly always on rigid ritual practice and faithful repetition of
the doctrine, not on any “altered states of consciousness” (Sharf
1995; 1998). As RobertQ1 Buswell (1992, p. 219) observes, the “tes-
timony of Korean [Zen] monastic community [...] suggests that a
disciplined life, not the transformative experience of enlighten-
ment” is the most important element in this form of religion.
Stephan Beyer (1973) argues likewise that in the Tibetan
Tantric rites he had observed, the visualization of deities always
took place in a ritual context, while rhythmically reciting a text;
this made visualization so difficult that even high-ranking
incarnate lamas admitted that they really could not master it.
In Theravada Buddhism, the so-called ma
¯
rga-texts (“path
texts”), regarded as meditation manuals, function “more as
sacred talismans than as practical guides” (Sharf 1995, p. 241).
Prior to the 19th century “Protestant Buddhism,” which was a
counter-reaction to colonialism and Christian missionary
efforts, meditation mostly meant the recitation of Pali texts
pertaining to meditation. Even today, most monks consider
nirvana to be unattainable and rarely engage in meditation
(Sharf 1995, pp. 241–42; 1998, pp. 105–106; see also Bond
1988; Gombrich 1988).
Also, in Zen monasteries the monks are primarily interested in
ceremonial repertoires and mastering vast collection of ko
ˆ
ans.
Even the Japanese terms for “experience,” keiken and taiken,
were actually coined at the end of the 19th century to translate
the German Erlebnis and the English “experience.” Words
such as satori do not originally refer to “enlightenment” as an
unmediated experience, but rather, to the full comprehension
of the Buddhist doctrines. Physical discipline and ritual compe-
tence are emphasized at the cost of inner experience (Sharf
1995, pp. 247–49). It is the faithful transmission of bodies of doc-
trine or of ritual practice that is important. The texts that speak of
meditative experience are not first-person reports but rather
elaborations of doctrinal ideals. Buddhist monks are explicitly
forbidden from vaunting their spiritual accomplishments in
public (Sharf 1995, p. 236).
We may thus conclude that in the Buddhist traditions medita-
tion is a heavily ritualized practice. An explicit emphasis on some
kind of transformative subjective experience as the ultimate goal
of this activity is a modern Western idea having its roots in the
Protestant ideal of lived experience at the heart of true religion
(Proudfoot 1985). Sharf, however, says nothing of the effects
that this practice might have on individuals without their
knowing.
B&L’s hypothesis, for its part, is based precisely on the
assumption that ritualized behavior cannot be explained with
reference to persons’ explicit motives. First, rituals have effects
of which the people concerned are not conscious; second,
rituals cannot be explained by their effects alone. Rituals
involve familiar actions (walking, etc.) that have been turned
into difficult tasks requiring such cognitive control which
“swamps” working memory.
It seems that the ko
ˆ
an rituals of Zen might work precisely this
way. A novice is given a paradoxical problem to be solved, such as
the question “what is the sound of one hand clapping.” After pon-
dering the question in meditation, the novice meets with the
master and tries to provide a solution. There is no correct sol-
ution, however; the whole point seems rather to be in that one
keeps going with the ritual process. At some point, the master
may accept some solution as the correct one, but the “correct-
ness” seems to be based on the master wishing to terminate
the process rather than on anything in the details of the solution
itself (see the classic collections of ko
ˆ
ans, Hekiganroku 1961;
Mumonkan 1966; cf. Buswell 1992, pp. 59, 150–58).
Thus, B&L’s theory might help explain some of the psychologi-
cal effects of rituals of meditation, without that we need to
ascribe to people motives and goals they obviously do not have.
Speculative interpretations can be replaced by an empirical
explanatory strategy to explore whether religious rituals actually
do swamp working memory.
One important implication for the study of religion is the effect
such swamping might have for persons’ attitude towards the doc-
trines in question. Sharf (1995, p. 236) points out that the prohi-
bition to vaunt one’s spiritual accomplishments has enabled
Buddhists to attribute spiritual experiences to past masters
without a need to find living masters claiming to have attained
to these experiences. Whitehouse (2004, pp. 67–68) argues in
the same vein that a frequent public rehearsal of religious teach-
ings ensures that persons will not try to provide novel and
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unorthodox interpretations of the doctrine. Whereas Whitehouse
presupposes that such blocking of “spontaneous exegetical reflec-
tion” takes place through a heavy routinization, B&L argue
exactly the opposite: it is precisely the non-routine nature of
rituals that does the swamping of working memory. Whether
this leads to a blocking of unauthorized doctrinal innovation, is
yet another empirical question that deserves to be explored.
Habit formation in Tourette Syndrome with
associated obsessive-compulsive behavior:
At the crossroads of neurobiological
modelling
Aribert Rothenberger, Veit Roessner, and Tobias
Banaschewski
Child and Adolescent Psychiatry, University of Goettingen, D –37075
Goettingen, Germany.
arothen@gwdg.de vroessn@gwdg.de tbanasc@gwdg.de
Abstract: Tourette Syndrome (TS) and Obsessive-Compulsive Disorder
(OCD) are highly associated and often it is difficult to differentiate their
symptomatology. In TS, habit forming neuronal systems may form habits
of their own – sometimes similar to ritualized behavior. However,
whereas in OCD merely the “affect-loop” is touched, in TS the
“sensorimotor-loop” plays the major role, although some overlap can be
seen in the clinical spectrum between TS and OCD. The latter is
mainly related to the “just-right” phenomenon which shows a clear
developmental course. An analogous behavioral model for TS and
OCD with reference to “just-right” is suggested.
Tourette Syndrome (TS) is frequently associated with, and is
pathophysiologically closely related to, obsessive-compulsive
behavior/disorder (OCB/OCD; Roessner et al. 2005). TS, with
its covert drumbeat of sensorimotor urges and its overt motor
and vocal tics (which may give relief from the urges with the con-
sequence of a “just-right” feeling), reveals that in this disorder
habit forming systems may form habits of their own (Leckman
& Riddle 2000; Leckman et al. 2006) – sometimes similar to
ritualized behavior.
Habits are assembled routines that link sensory cues (either
external or internal) with motor actions. Although no direct
causal link between TS/OCD and habits has been established,
there exists some evidence that patients with TS have impaired
habit learning. This is probably because of their striatal deficit,
which is based on a decreased inhibitory influence of the fast
spiking neurons (FSNs) over matrisomal cells (MSs). This
could allow the cortical sensorimotor inputs to more easily acti-
vate MSs, eliciting the premonitory urges experienced by individ-
uals with TS (Banaschewski et al. 2003; Leckman et al. 2006). It is
also suggested that FSNs are instrumental in orchestrating the
oscillatory activity of the MSs in the dorsal lateral striatum.
This seems to be related to normally occurring rhythmic oscil-
latory activity within basal ganglia circuits, which plays a key
role in the emergence and performance of regular voluntary
actions and habits. Further, these oscillations appear to be
linked with oscillations from cortical regions (e.g., prefrontal,
mesiofrontal) during the repetitive performance of learned beha-
viors and tic suppression (overview in Leckman et al. 2006).
Hence, different regions of the basal ganglia seem to oscillate
in synchrony with specific cortical, cerebellar, and thalamic
regions to guarantee neuronal homeostasis. It also implies that
irritations in basal ganglia functions may lead to dysbalanced tha-
lamocortical activity and thus to problems in habit forming and/
or habit execution, as it seems to be the case in TS. This view is
supported by the fact that electrical deep brain stimulation (e.g.,
thalamus) may work by re-establishing more normal tic/OCB
suppressing oscillatory patterns via its effect on striatal neurons
(Leckman et al. 2006). In this respect, the error detection
system of the anterior cingulate cortex (ACC) may play an
important role for the monitoring of such processes. Its activity
is increased in OCD and TS (Fitzgerald et al. 2005; Johannes
et al. 2001; 2002).
In attempting to explain OCB and its abnormal control
processes, Boyer & Lienard (B&L) give an interpretation of
Szechtman and Woody’s (2004) motivational model of OCD,
trying to investigate emotions, perceptions of specific infor-
mation, typical actions, and inhibition or disinhibition of auto-
matic routines. The model is focusing on the “detection of
potential danger” and the following steps. Unfortunately,
B&L’s interpretation of the model did not have a look at the
association of OCB with TS but, fortunately, a slightly modified
version of the model itself can be developed for TS as well
(Fig. 1). The main difference is the first step where in OCB/
OCD the detection system recognizes a cognitive-emotional dis-
sonance, whereas in TS a sensorimotor dissonance is prevailing
without any anxiety. As a consequence, the “affect-loop” is not
touched in TS while disturbances in the “sensorimotor-loop”
are counter-balanced by repetitively acting out the tics which
sometimes may mimic ritualized-compulsive behavior, but do
not reflect activity of a “security-related-program-loop.”
Similarly, this seems to be the case for another core process of
ritualized action, namely safety motivation triggered arousal (see
target article, sect. 3.3). The authors assume that the arousal state
may bias the appraisal system in such a way that “just right” or
“closure” experience is delayed. Although the latter assumption
is close to what happens in patients with TS who show hyperar-
ousal (Kirov et al., in press; Kostanecka-Endres et al. 2003), here
again the aspect of danger/safety does not play any role concern-
ing the “just-right” phenomenon in TS.
Thus, the link between OCB/OCD and TS is quite complex
(Roessner et al. 2005) and it yields that the disorder specificity
of such explanatory models of frontostriatal disorders like TS
and OCD is not easy to grasp. This point is strengthened by
Figure 1 (Rothenberger et al.). Cognitive-Sensorimotor Model
of Tic-performance. Adapted from Szechtman and Woody’s
(2004) Emotional Model on obsessive-compulsive behavior as
interpreted by Boyer & Lienard. White rectangles correspond
to distinct systems activated, light grey boxes to behavioral
results and dark grey boxes to aspects of the processing.
Suppression of tics by activating frontal lobes is possible at any
stage of the process.
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the information that in TS there exists a high frequency of
particular sets of associated repetitive behaviors (e.g., nail
biting, tooth grinding, nose picking) without the typical compul-
sory elements (Roger Freeman, personal communication),
although these behavioral sets might sometimes be included in
more complex OCB and rituals.
Finally, B&L have discussed the developmental aspect of
ritualized behavior and focused on the “just-right” phenomenon.
They have put it in relationship to anxiety, harm, separation and
fears. This might be partly true, especially since many children
and adults with OCD and/or TS report separation anxiety in
early years. However, in the absence of a proper causal or predic-
tor model a merely cognitive developmental framework would be
also tenable. Especially since, in TS, the sensorimotor phenom-
ena and the related behavior show a clear cognitively determined
developmental course independent of the duration of the dis-
order. Usually, children are aware of sensorimotor phenomena
as ego-dystonic around the age of ten only (Banaschewski et al.
2003). Also, children with early-onset of OCD have a higher
association with TS and probably show more special repetitive
behaviors (e.g., nose picking; Roger Freeman, personal com-
munication; Roessner et al. 2005). But it is unclear if they are
at higher risk for ritualized behavior in general. Hence, the
suggested development of “functional calibration” needs to be
included in such models.
To sum up, it may be assumed that in children with TS/OCD
spectrum, the coordination and orchestration function of the
striatum is more labile and patients need early therapeutic
support to successfully calibrate their central nervous habit-
forming systems with growth and maturation.
Rituals are rational for the imperfect
experimentalist
M. D. Rutherford
Department of Psychology, Neuroscience and Behaviour, McMaster
University, Hamilton, Ontario L8S 4K1, Canada.
rutherm@mcmaster.ca
www.science.mcmaster.ca/psychology/rutherford
Abstract: Humans are, by design, imperfect experimentalists. The cost of
testing each step of a process exceeds the benefit of knowing which steps
can be eliminated. To an outsider who knows which steps are superfluous,
the actors appear superstitious, even ridiculous. Nonetheless, the exact
duplication of all steps is rational for the imperfect experimentalist.
The case of ritual in autism illustrates this point.
People are imperfect experimentalists. Indeed, in the face of
uncertain information, people may not seek and may actively
avoid the information that would be necessary to test their
working hypotheses, a phenomenon that has been called the
“confirmation bias” (Wason 1960). Although this bias leads to
inaccuracies, people are imperfect experimentalists by design.
In the processes that are important to humans – cooking, child-
birth, hunting, or warfare, for example – the cost of meticulously
changing each variable to measure its effect on the outcome is
much more than the benefit of that knowledge. If a person
believes that boiling water during childbirth leads to a healthy
birth, there will never be a point at which experimentally elimi-
nating that step is worth the risk of losing a baby. If one believes
that carrying a particular talisman into battle leads to success,
there will never be a case when leaving it at home in order to
test its value will be worth the risk of losing the battle. Humans
are imperfect experimentalists by design, and a result of having
imperfect information is that it is rational to follow a ritual,
even if some steps in that ritual appear far removed from the ulti-
mate goal of the process.
The model proposed by Boyer & Lienard (B&L) explains
the ritualized behavior of humans as a product of a cognitive
Precaution System. In fact, ritualized behaviors are a result of a
more general decision-making process, of which precaution
taking is a specific subset. Ritual is rational in situations where
one has incomplete information. Imagine that one has to
decide whether a precaution has been taken, for example, to
ensure that a door has been locked. Once one is certain that
the door has been locked, one can attend to something else.
While the door is out of sight, one must decide between choice
A (the door has been checked, I can relax) or choice B (the
door may not have been checked, I need to check it.) Formally,
this problem can be represented in terms of Signal Detection
Theory. Deciding to check the door, if it is secure, is a False
Alarm, if not secure, this action is a Hit. Leaving an unlocked
door unchecked is a Miss, and leaving the door when it is
secure is a Correct Negative. Signal Detection Theory describes
how humans make such a decision under conditions of uncer-
tainty, and it is capable of dealing with changes in the relative
cost of each kind of mistake. In the case of the hypothetical Pre-
caution System that B&L describe, the costs of each mistake are
strongly unequal: the cost of a Miss (if one is attacked because of
the unlocked door) is much greater than the cost of a False
Alarm. Therefore, and entirely consistent with B&L’s suggestion,
there may be a natural bias towards checking.
However, the case of precautions is only one extreme type of
decision-making problem, one in which the relative costs of the
two types of mistakes are radically unequal. There are other
more mundane examples of this problem, in which the cost of
each mistake is less unequal, and these cases may also lead to
ritual behaviors if people have incomplete information. Take
cooking as an example. If a recipe has worked for an individual,
for her mother and for her grandmother, it will rarely be worth
eliminating an ingredient (or step) to test whether it was necessary.
The risk is not dire: one stands to lose a meal, but even this rela-
tively lower cost is not worth taking most of the time. Here too,
ritualized behaviors may be maintained, if somewhat less inflexibly.
B&L describe typical behavior and behavior in some neuro-
logical disorders, but they fail to mention one disorder that is
defined by its ritualistic behavior: autism. Can the rituals of indi-
viduals with autism be understood in term of B&L’s model? Yes,
ritual is rational for those with autism but only if we appreciate
that the B&L model is a specific instance of a more general
decision-making strategy. Autism is a developmental disorder
that is characterized by difficulties in social cognition, language
delay, and an unusual attraction to ritualistic behavior. Children
and adults with autism can be extremely tied to rituals that they
feel compelled to perform, and routines become very rigid. A
child with autism may insist that the family remote controls be
lined up in a particular order and be touching each other, or
that the pillows on the couch be in a particular configuration,
or that photos on a shelf be displayed at a particular angle, for
example. Although other developmental disorders such as schizo-
phrenia and some learning disabilities may include ritualistic
behavior, the rituals of autism are distinct in kind (Baron-
Cohen & Wheelwright 1999) and quantity (Szatmari et al. 1989).
In spite of this, B&L do not mention autism in their discussion.
The rituals of autism may be difficult to understand in the rela-
tively narrow view of rituals as a product of a cognitive Precaution
System, but easier to understand if seen as a product of a more
general decision-making strategy, of which precaution is a
subset. Children with autism cannot easily make use of social infor-
mation due to their difficulty understanding and making infer-
ences from the mental states of others, and incomplete
information leads to a dependence on rituals. In the autism litera-
ture, explanations for rituals are offered that describe a homeo-
static mechanism: children with autism perform a ritual to
reduce arousal, or to return to a more comfortable state (Hutt &
Hutt 1970). This explanation is a viable proximal explanation but
lacks any attempt at understanding the ultimate causes of the ritua-
lized behavior. In contrast, we can understand the ritualized beha-
vior of children with autism as an attempt to continue to produce
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acceptable outcomes when those with autism have imperfect
information. Those with autism are dependent upon ritual pre-
cisely because they have imperfect information, particularly
social information. One result of this perspective is the prediction
that those with autism may be even more tied to rituals in
situations that are more socially demanding. Indeed, repetitive
behaviors are more pronounced when children with autism are
in the presence of unfamiliar adults (compared to familiar
adults; Charlop 1983). For imperfect experimentalists with or
without autism, the benefits of adhering to a routine that works
exceed the risks of testing each step.
Universal sex-specific instantiations of
obsessive-compulsive disorder
Gad Saad
Marketing Department, John Molson School of Business, Concordia University,
Montreal, Quebec H3G 1M8, Canada.
gadsaad@jmsb.concordia.ca
Abstract: Numerous sex differences in obsessive-compulsive disorder
(OCD) instantiations are likely universal, as the associated evolutionary
threats and concerns onto which they map were differentially important
to the two sexes. Hence, although some ritualized behaviors or thoughts
are indeed culture-specific, others are both culturally and temporally
invariant as they are rooted in universal Darwinian etiologies (e.g., the
sex differences in OCD symptomatology posited here).
Boyer & Lienard (B&L) have heeded admirably E. O. Wilson’s
call for the development of consilient research paradigms
(Wilson 1998). They have managed to unify disparate research
traditions, operating at both the proximate and ultimate levels
of analyses, into a coherent and parsimonious model of ritualized
behavior. I fully concur with the central premise that obsessive-
compulsive disorder (OCD) involves the over-activation of
warning systems in evolutionarily relevant areas (Saad 2006), a
tenet that is consistent with B&L’s ninth proposition (P9;
target article, sect. 7.5). In their first proposition (P1; sect. 7.1),
B&L posit that fitness-relevant life cycle variables (including bio-
logical sex) should serve as strong predictors of the rate of occur-
rence, the strength, and the contents of intrusive thoughts. This is
a very reasonable proposition whose explanatory power can be
augmented in two ways: (1) recognizing that P1 applies to a
much broader range of OCD instantiations (i.e., it need not be
restricted to intrusive thoughts); (2) positing specific hypotheses
for a given life cycle variable (in this case, biological sex). Specifi-
cally, to the extent that one’s biological sex is a defining human
polymorphism (certainly the case for a sexually reproducing
species), one might reasonably expect sex differences in the
symptomatology of OCD (see Saad [in press a] for additional
details). This point serves as the crux of my commentary.
Although many social and physical ancestral threats are equally
relevant to both sexes (hence no sex differences are expected in
OCD manifestations that map onto these threats), some evolutio-
narily relevant dangers tend to be more sex-specific (and hence
yield sex-specific instantiations of OCD). Intrusive thoughts
related to the harming of one’s infant are more common in
women while sexual compulsions are more frequent in men.
Women’s contamination fears seem to fluctuate as a function of
various important fitness-relevant stages including pregnancy
status and menstrual cycle. Each of the latter sex-specific findings
is perfectly congruent with evolutionary-based predictions. I
would posit that ruminative thinking associated with loss of
social status (e.g., “I am sure that I say idiotic things at
company meetings causing everyone to think that I am a
moronic buffoon”) is more likely to occur in men, whereas that
linked to beauty-related threats (e.g., “I am certain that people
think that I am hideously fat and hairy”) is much more
common in women. In general then, while many ritualized
behaviors might indeed be culture-specific (as per B&L’s tenth
proposition, P10; sect. 7.5), numerous sex-specific forms of
OCD-related ritualized behaviors are likely universal as they
map onto sex-specific evolutionarily relevant threats and con-
cerns. Tangentially, in discussing culture-specific examples of
ritualized behavior, B&L allude to purity of thought concerns
in Islam (sect. 7.5). I am uncertain of this example’s validity
given that this concern is equally inherent to many other reli-
gions. For example, religious and moral scrupulosity has been
documented quite extensively amongst Christians and Jews
(both Inigo de Loyola and Martin Luther were thought to
suffer from religious scrupulosity). Hence, religious scrupulosity
along with its various forms of ritualized behavior is more likely
linked to religiosity per se (irrespective of the religious tradition).
My present point with regard to the evolutionary roots of sex
differences in the instantiation of OCD symptoms applies to
other psychiatric conditions as well (see Kessler [1998] for a dis-
cussion of sex differences across a wide range of psychiatric con-
ditions, albeit void of any evolutionary-based theorizing). I have
argued elsewhere that numerous psychiatric afflictions appear
to have universal sex-specific manifestations either in their
forms and/or their incidence across the two sexes. For
example, pornography addicts and pathological gamblers are
overwhelmingly more likely to be male, whereas compulsive
buyers and individuals suffering from eating disorders are extre-
mely more likely to be females (Saad, in press b). These sex-
specific effects are both temporally and culturally invariant and
hence seem to have a Darwinian etiology. Incidentally, B&L
state that hoarding is a form of OCD that is outside of their evol-
utionary purview perhaps because the ritualized behaviors in
hoarding are not as apparent as those in other forms of OCD. I
should mention that the items that women hoard when
engaged in a compulsive buying binge typically relate to
beauty-enhancing products, hence the evolutionary-based mech-
anisms are apparent in this case (Saad, in press b). Evolutiona-
rily-congruent findings/explanations have been obtained/
proposed for a wide range of psychiatric and medical disorders
including De Cle
´
rambault’s syndrome (Bru¨ ne 2001; Bru¨ne &
Schro
¨
der 2003), erectile dysfunction (Cellerino & Jannini 2005;
Gofrit 2006), perfectionism (Dunn et al. 2005), envy
(Habimana & Masse
´
2000; Saad & Gill 2005), social stress
(Troisi 2001), sexual disorders (Troisi 2003), persecutory delu-
sions (Walston et al. 1998; Zolotova & Bru¨ne 2006), depression
(Mackey & Immerman 2000), body dysmorphic disorder (Phil-
lips et al. 2006), and suicide (Saad, in press a). Generally speak-
ing, key triggers of envy, suicide, perfectionism, social stress,
body dismorphic disorder, erotomania, and persecutory
delusions assort along sex-specific lines precisely because many
evolutionary threats are differentially important to the two sexes.
Two final points: First, to the extent that B&L are applying an
evolutionary-based approach in exploring ritualized behavior
(including OCD), two non-cited albeit highly relevant papers are
those by Polimeni et al. (2005) and Feygin et al. (2006). The
former paper argues for the adaptive benefits of OCD via a
group selectionist argument, whereas the latter article explores
the manifestations of OCD in several domains of evolutionary
import including parental and romantic love. Second, B&L repeat-
edly state that there are no evolutionary/adaptive reasons for
humans to engage in wasteful rituals (e.g., the opening line of
the epilogue, sect. 9.3). This is puzzling given that B&L are well
aware of the costly signaling mechanisms that explain the evol-
utionary roots of such behaviors (cf. Sosis 2003; Sosis & Alcorta
2003; Sosis & Bressler 2003; also, Hagen & Bryant 2003). The
latter point notwithstanding, I accept B&L’s distinction between
ritualized behaviors and rituals.
To summarize, B&L have provided a powerful conceptual
model for exploring ritualized behavior. One proposed area for
future research would be to explore universal sex-specific instan-
tiations of ritualized behaviors (as occurs with OCD), a sugges-
tion directly relevant to B&L’s propositions 1, 9, and 10.
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Morbid jealousy as a function of fitness-
related life-cycle dimensions
Lucas D. Schipper,
a
Judith A. Easton,
b
and Todd
K. Shackelford
a
a
Department of Psychology, Florida Atlantic University, Davie, FL 33314;
b
Department of Psychology, The University of Texas at Austin, Austin,
TX 78712.
lschippe@fau.edu jeaston1@mail.utexas.edu
tshackel@fau.edu http://www.ToddKShackelford.com
Abstract: We suggest that morbid jealousy falls on the extreme end of a
jealousy continuum. Thus, many features associated with normal jealousy
will be present in individuals diagnosed with morbid jealousy. We apply
Boyer & Lienard’s (B&L’s) prediction one (P1; target article, sect. 7.1) to
morbid jealousy, suggesting that fitness-related life-cycle dimensions
predict sensitivity to cues, and frequency, intensity, and content of
intrusive thoughts of partner infidelity.
Jealousy is a universally experienced emotion proposed to be
serving the adaptive purpose of preventing costly partner infide-
lity (Buss 2003). Jealousy mechanisms may exist on a normally
distributed continuum, ranging from extreme hyposensitivity to
extreme hypersensitivity (Buss 2000; Easton et al., in press). Indi-
viduals diagnosed with Delusional Disorder, Jealous Type (Diag-
nostic and Statistical Manual of Mental Disorders; American
Psychiatric Association 2000) or “morbid jealousy” display this
perceptual hypersensitivity and tend to exhibit extreme beha-
viors. These individuals incessantly accuse their partner of infide-
lity and often without actual verification (Kingham & Gordon
2004; Shepherd 1961). They monitor their partner’s whereabouts
by calling them incessantly, following their partner everywhere,
and spying on their partner (Enoch & Trethowan 1979;
Vauhkonen 1968). They show up unexpectedly at their partner’s
workplace or home. They use non-physical and physical abuse
against their partner and may attempt to murder or actually
murder their partner as a result of these intense and persistent
feelings of jealousy (Buss 2000; Kingham & Gordon 2004;
Mowat 1966).
If morbid jealousy is on an extreme end of a jealousy conti-
nuum, we hypothesize that individuals with normal jealousy and
individuals diagnosed with morbid jealousy may experience
many of the same intrusive thoughts and behaviors. As Boyer &
Lienard (B&L) note, an important distinction lies not in the
thought content but in the appraisal of those thoughts. Consistent
with B&L’s Precaution System Model, hypersensitive jealousy
mechanisms may not be dysfunctional in all cases; in fact, by
over-interpreting specific cues to partner infidelity, the mechan-
isms may serve the adaptive purpose of preventing partner infide-
lity. The perception, interpretation, and reaction to cues to
partner infidelity may depend on specific contextual factors. We
argue that the position of an individual along fitness-related life-
cycle dimensions will predict the sensitivity to cues to partner infi-
delity and the frequency, intensity, and contents of intrusive
thoughts of partner infidelity. These fitness-related life-cycle
dimensions are experienced in a number of different ways.
It has been shown that men more than women are upset when
asked to imagine their partner engaging in sexual intercourse
with someone else, whereas women more than men are upset
when asked to imagine their partner falling in love with
someone else (Buss et al. 1992; Buss et al. 1999). Thus, men
are more apt to display sexual jealousy whereas women are
more apt to display emotional jealousy. We expect to find the
same pattern in individuals diagnosed with morbid jealousy,
such that a greater percentage of men than women diagnosed
with morbid jealousy will focus on a partner’s sexual infidelity,
and that a greater percentage of women than men diagnosed
with morbid jealousy will focus on a partner’s emotional infide-
lity. Furthermore, we expect that men diagnosed with morbid
jealousy will obsess on the details of a partner’s sexual contact
with other men and that women diagnosed with morbid jealousy
will obsess on the details of a partner’s emotional contact with
other women.
Research has also shown that men more than women report a
potential rival’s social status/wealth as a jealousy eliciting
characteristic and that women more than men report physical
attractiveness/youth as a jealousy eliciting characteristic in a
potential rival (Brase et al. 2004; Buss et al. 2000). We expect
to find the same thought pattern in men and women diagnosed
with morbid jealousy. In fact, the intensity and frequency of
these thoughts may vary as a function of fitness-related life-
cycle dimensions. For example, a young man with few resources
may be especially likely to focus on a rival’s social status/
wealth. An aging woman may be particularly attuned to the
attractiveness/youth of potential rivals.
We also expect shifts in mate value in one partner relative to the
other partner to predict sensitivity to cues of infidelity, and the
intensity and frequency of jealous thoughts and feelings. Individual
mate value can increase. One partner may experience sudden
financial success, career advancement, or social status enhance-
ment, or perhaps increased physical attractiveness through exer-
cise, dieting, or cosmetic surgery. Individual mate value can also
decrease. One partner may physically age faster than the other,
become seriously ill, handicapped, or infertile. A career setback
or a loss in social status may also decrease mate value. The individ-
ual with the newly acquired lower mate value may feel less attrac-
tive, sexually inadequate, or unworthy as a partner; and may now
be perceived by their partner as an unworthy mate (Buss 2000).
It may benefit those individuals with the lower mate value to
attend to this discrepancy and to be more vigilant in their mate
guarding efforts, including experiencing frequent and intense feel-
ings of jealousy, increasing their sensitivity to cues of partner infi-
delity, and behaving accordingly to prevent partner infidelity.
Finally, we expect rates of actual partner infidelity to reflect the
sensitivity to and the frequency, intensity, and contents of intru-
sive thoughts of partner infidelity. A diagnosis of morbid jealousy
requires that the individual’s partner is not or has not been
unfaithful. However, if jealousy mechanisms are designed to per-
ceive cues to partner infidelity, it is possible that these hyper-
sensitive jealousy mechanisms are functioning as designed, that
is, accurately detecting partner infidelity. Perhaps these persist-
ent and obtrusive feelings of jealousy are grounded in reality.
By not considering the functionality of jealousy mechanisms, clin-
icians may be too quick to dismiss the perception of their patients.
A complete understanding of morbid jealousy may come from
examining morbid jealousy in relation to normal jealousy. We
concur with B&L’s Precaution System Model proposal that intru-
sive thoughts are generally not dysfunctional; and we offer that an
examination of the individual context through fitness-related life-
cycle dimensions may predict sensitivity to cues to partner infide-
lity, and the frequency, intensity, and content of intrusive
thoughts of partner infidelity. The application of this model to
morbid jealousy may help researchers and clinicians enrich
their understanding of the disorder and thereby improve
treatment of individuals diagnosed with morbid jealousy.
Critical developmental periods of increased
plasticity program ritualized behavior
James E. Swain
Child Study Center, Yale University School of Medicine, New Haven,
CT 06520.
james.swain@yale.edu
Abstract: The consideration of humans going through sensitive periods
of life, such as childhood and the early postpartum, may be helpful in
understanding the cognitive and evolutionary puzzle of human rituals.
During such periods, certain brain systems may mediate an increased
susceptibility to learn new behaviors, rational or irrational.
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The apparently irrational ritual behaviors discussed by Boyer &
Lienard (B&L) may be related to the double-edged sword of
having windows of increased plasticity. There is considerable evi-
dence from epidemiology, ontogeny, ethology, and neurobiology
that patterns of “normal” and adaptive ritual through childhood,
romantic love, family life, and religious experience overlap with
obsessive-compulsive disorder (OCD) (Feygin et al. 2006).
During vulnerable periods, the capacity to recruit reward
systems to motivate and learn survival behaviors without
reasoned justification might confer significant evolutionary
advantages. However, these periods might also render humans
susceptible to irrational or psychopathological behaviors
transmitted through the impact of comorbid psychopathology,
culture and family.
Much of human behavior may be thought of as the result of
reward-seeking or harm avoidance so that one might imagine
behavior is based on an overall cost function associated to each
action in which rational decisions are based on the conscious
weighing of “pro’s and con’s.” However, when time is limited,
stress is increased, or dangers are great, perhaps survival has
evolutionarily favored brains that acted without rational
review – that is, that performed rituals. Ritual behavior, then,
would include behaviors that do not stand up to rational
review, such as behaviors in which faith, rather than verifiable
facts, determine actions. Children may represent a developmen-
tal window when threats are greater, cognitive capacity is lower,
and perhaps even reward/learning circuits are primed to accept
whatever they are told, with little rational review. Further, the
behavior of children is influenced by the introduction of false
positives and negatives. For example, children are told, and
they accept, that if they do certain things then fictional entities
such as Santa Claus or religious figures will be pleased and
perhaps reward them. In the case of the Santa Claus myth,
actual material rewards are provided by parents in addition to
other parental caring behaviors. Alternatively, children may be
threatened with negatives such as imaginary monsters or reli-
gious concepts like “hell” for failure to conform to whatever is
required of them. Ideas of harm befalling a parent (reminiscent
of OCD) may also be introduced. The capacity to be irrational,
then, may be programmed during childhood to support a wide
variety of fallacious cognitions that may go on to be part of
rituals and OCD. It appears that a tendency toward magical
thinking may underlie links between superstition and OCD
severity (Einstein & Menzies 2004). In the case of religious
beliefs, the acceptance of patently un-testable hypotheses (such
as the nature of life after death) can even be rewarded, under
the general guise of “faith.” It is an interesting observation that
early-onset OCD is more severe (Rosario-Campos et al. 2001).
It might be interesting to study the converse – that is, would a
delay of ritual-based teachings to mid-late adolescence result in
a decrease in ritual behavior and OCD?
As we might predict, then, increased religiosity (significantly
mediated by childhood instruction) is associated with increased
OCD. For example, Catholics with a high or moderate degree
of religiosity scored higher on measures of OCD-related obses-
sional thoughts, compulsive washing, intolerance for uncertainty,
need to control thoughts, beliefs about the importance of
thoughts, and inflated responsibility, than did less religious
Catholics (Sica et al. 2002). In another study using self-report
questionnaires, differences in OCD-related phenomena
between highly religious Protestants, moderately religious Pro-
testants, and atheist/agnostic participants drawn from an under-
graduate sample were studied (Abramowitz et al. 2004). Highly
religious versus moderately religious Protestants reported
greater obsession symptoms and compulsive washing. Also, com-
pared with atheists and agnostics, the highly religious had more
obsession symptoms, including compulsive washing, intolerance
for uncertainty, need to control thoughts, beliefs about the
importance of thoughts, and inflated responsibility. In another
study of 45 outpatients with OCD, 42% of patients had religious
obsessions (Tek & Ulug 2001). Relationships between religious
practices and OCD have also been reported among Hindus
(Khanna & Channabasavanna 1988), Orthodox Jews (Green-
berg & Shefler 2002), and Muslims (de Bilbao & Giannakopoulos
2005), underscoring the influence of particular religious
affiliations on the expression of OCD.
It is likely that many brain systems are involved in ritual,
including the fronto-striatal networks mentioned by B&L. Also
of particular importance would be the reward systems that nor-
mally motivate various behaviors involved in learning and affilia-
tion (Depue & Morrone-Strupinsky 2005). These might,
however, be vulnerable to hijacking, such as in the acquisition
of irrational, ritualistic, and pathological behaviors in OCD
(Leckman & Mayes 1999), and addictions (Kufahl et al. 2005;
Swain et al. 2005). Some of these systems have been shown to
be activated in parents who are also undergoing a period of
increased stress, learning, and preoccupation in the first few
months after childbirth (Leckman et al. 1999). Several groups
are also contributing to this field using different functional
brain imaging experimental paradigms and populations (Swain
et al., in press). These imaging studies hold the promise of iden-
tifying brain circuits associated with the formation of parent–
infant attachment during the critical postpartum period. Some
of these areas overlap with the ritual areas suggested by B&L
and with OCD regions (Friedlander & Desrocher 2006). For
example, first-time parents responding to their own infant’s
cries versus those of other infants’ at 2 weeks postpartum, had
activated basal ganglia, orbitofrontal cortex and caudate. These
activations were also correlated with measures of OCD-like post-
partum preoccupations.
Certain neurotransmitters may be critical to rituals. For
example, CSF levels of the affiliative neuropeptide oxytocin are
elevated in some individuals with OCD (Leckman et al. 1994).
Another example is serotonin since serotonergic drugs are
commonly used to treat OCD. In addition, serotonin has been
associated with spiritual experiences (Borg et al. 2003), and
OCD-related moral or religious scrupulosity can be effectively
treated with serotonin reuptake blockers (Fallon et al. 1990).
Indeed, much more research is needed on the common and dis-
tinct neural correlates of various OCD symptom dimensions with
symptom provocation paradigms, combined with neuropsycholo-
gical tasks and neuroimaging techniques. Certain groups that
bear particular attention include “normal” subjects during critical
periods such as childhood, or high stress.
ACKNOWLEDGMENTS
J. E. Swain is supported by a grant from the National Alliance for
Research on Schizophrenia and Depression. Thanks to J. D. Swain for
providing valuable comments on an earlier draft of this commentary.
The evolved architecture of hazard
management: Risk detection reasoning and
the motivational computation of threat
magnitudes
John Tooby
a
and Leda Cosmides
b
a
Department of Anthropology, Center for Evolutionary Psychology, University
of California, Santa Barbara, CA 93106-3210;
b
Department of Psychology,
Center for Evolutionary Psychology, University of California, Santa Barbara,
CA 93106.
tooby@anth.ucsb.edu http://www.psych.ucsb.edu/research/cep/
cosmides@psych.ucsb.edu
http://www.psych.ucsb.edu/research/cep/
Abstract: The architecture of the hazard management system underlying
precautionary behavior makes functional sense, given the adaptive
computational problems it evolved to solve. Many seeming infelicities
in its outputs, such as behavior with “apparent lack of rational
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BEHAVIORAL AND BRAIN SCIENCES (2006) 29:6 37

motivation” or disproportionality, are susceptibilities that derive from the
sheer computational difficulty posed by the problem of cost-effectively
deploying countermeasures to rare, harmful threats.
Boyer & Lienard’s (B&L’s) landmark work represents a decisive
advance in our understanding of the evolutionary psychology of
ritual behavior, viewed as a byproduct of adaptations for avoiding
danger. We strongly endorse the view that there is an evolved,
species-typical suite of neurocomputational adaptations designed
to deal effectively with dangers and the deployment of countermea-
sures – what we have called hazard management or precaution
systems (Fiddick et al. 2000). We also agree that the themes of
ancestrally recurrent danger (e.g., contagion, danger to offspring)
that pervade obsessive-compulsive disorder (OCD) ideation,
together with the hyperactivation of precautionary checking sub-
routines, indicate that OCD results from breakdowns in these
evolved systems (Cosmides & Tooby 1999). In particular, we
have been pursuing the hypothesis that there is an evolved
domain-specific inferential specialization designed to reason
about whether an appropriate precaution has been taken, con-
ditioned on the presence of the danger it protects against. A
growing body of evidence suggests that such a risk detection
specialization exists (somewhat parallel to the cheater detection
system) and is cognitively distinct (Fiddick et al. 2000), neuropsy-
chologically dissociable (e.g., from reasoning about social contracts;
Stone et al. 2002), and involves distinct patterns of neural acti-
vation, as judged by neuroimaging findings (Ermer et al., in press).
This risk detection reasoning (and attentional) subsystem
appears to use cognitive primitives at the level of hazard
i
(present/absent), countermeasure for i (in effect, not in effect),
and it draws attention to conditions in which a danger may be
present but its appropriate precaution may not have been
taken. We believe that when this checking subroutine produces
the inference that a specific hazard
i
might be present in the
absence of its specifically associated countermeasure, this
output potentiates the regulatory circuitry governing motivations
to take associated safeguards. We suspect that this same system,
to accomplish its detection function for evolutionarily prepared
dangers, accesses what B&L call the Potential Hazard Reper-
toire, and the Evolutionary Precaution Repertoire. We therefore
view these as evolutionarily prepared subsets of two more
encompassing repertoires that include all represented hazards,
and all represented countermeasures, respectively. That is, the
risk detection subsystem not only functionally links “innate”
countermeasures (e.g., washing) to ancestral hazards (e.g.,
disease exposure), but also links evolutionarily novel countermea-
sures (e.g., backing up) to evolutionary novel dangers (e.g., hard
disk crashes).
The adaptive computational problems posed by reasoning,
however, are dwarfed by the magnitude of the design problems
posed by the task of computing valuations in a fitness enhancing
way (Tooby et al. 2004). The selective intensity of an adaptive
problem is a function of the frequency of the selective event, mul-
tiplied by the magnitude of its fitness consequences. Events that
(1) happen frequently over the lifespan, (2) where outcomes
follow rapidly, and (3) where outcomes can be readily assayed
for their value allow the evolution of feedback systems that
shape and weight actions reliably (allowing, e.g., motor skill acqui-
sition). In contrast, a selectively significant set of detrimental
events (threats) will be sufficiently harmful (e.g., disease, preda-
tion, ambush, social disgrace) to make it potentially cost-effective
to take countermeasures even when their incidence is low.
Because their incidence is low, however, sampling error and a
paucity of observations will make uncertainty great, accurate ascer-
tainment of their true probabilities difficult, and the change in
their probability associated with a given countermeasure or pre-
dictive cue even harder to determine. Indeed, a successful precau-
tion may preclude a harmful event from happening, so that it is
never observed by an individual. How can the observer tell
whether a threat has disappeared, whether the precaution
remains necessary, or whether good luck was responsible for the
apparent disappearance of a threat that remains real? The rarer
an event is, the more its true probability will be hidden from an
observer among a large range of possible values.
Indeed, because many threats are produced by design by
antagonistically co-evolving organisms, selection often makes
threats maximally unpredictable to their victims. Yet the motiva-
tional system, in order to allocate effort among possible precau-
tionary actions and other fitness-promoting activities, must
compute and assign to each threat (given a set of cues) a value,
as an approximate function of its expected cost and its expected
probability. That is, for each represented threat, the system
must compute a regulatory variable: a threat index. It also
needs to compute values for cues that predict changes in the
probability of the threat, as well as values for the effectiveness
of countermeasures. (The categorization of threats ought not to
be just a function of their “objective” external resemblance to
each other, but more importantly of how similar their counter-
measures are: That is, “pollution” is an evolved idea not
because it represents a single kind of threat – it does not – but
because the environmental threats it lumps together can be atte-
nuated using the same kinds of countermeasures.) Because of
their different evidentiary bases, threat indices cannot be com-
puted in the same way in which positive payoffs driving
reward-seeking decisions can be. Accordingly, the precautionary
system is adaptively designed to produce feelings of “compul-
sion” (action motivated in a way that is divorced from any proxi-
mate goal or confirmatory payoff – unlike, say, foraging).
Normally, precautionary compulsions should be trumped when-
ever situations invite alternative actions whose payoffs exceed the
threat index. Although what might be called optimal defense
theory has some powerful analogies with optimal foraging
theory, it also has disanalogies which would have selected for
the hazard management system to become a computationally
differentiated part of the motivational architecture.
A well-engineered system should supplement observations of
the incidence of rare costly events and countermeasures with
other sources of information. These include (1) correlated cues
to conditions of heightened threat (Neyman-Pearsonian decision
theory suggests that the system ought to be biased to overinter-
pret the diagnosticity of candidate predictors, as in post-
traumatic stress disorder [PTSD]); (2) non-frequentist causal
models of countermeasures (e.g., physical barriers to threats);
(3) decoupled imaginative simulations (Tooby & Cosmides
1990) and quasi-counterfactual representations such as “near
misses” (when dysregulated, these recalibrations constitute
obsessions); (4) possible transgenerational epigenetic reweight-
ing (see Tooby et al. 2003); (5) genetic inheritance (the heritable
personality dimension psychoneuroticism may exist as an
adaptation to allow local and transgenerational recalibration of
threat indices through genetic or epigenetic reweighting (see
Tooby et al. 2003); and (6) social sources of information.
The social dimension especially illuminates collective ritual
behavior. Observations gathered by multiple conspecifics
provide more accurate estimates of actual threat magnitu-
des – the adaptationist rationale for circuits that reset threat
indices partly based on observed fear reactions in others (Cook
& Mineka 1987). Moreover, the high uncertainty hovering over
incidences and countermeasure effectiveness leaves the hazard
system susceptible to error, volatile reweighting, individual
differences, and social entrainment (including manipulation).
Seeing others devote considerable effort to a collective ritual
presented as a countermeasure advertises their threat indices,
inducing observers to reweight. Finally, because of human
improvisational intelligence (Tooby & DeVore 1987), we think
there is a proper domain for some precautionary ritual behavior,
where it functions as preparation for complexly managed, instru-
mental activity in dangerous and unpredictable environments
whose negotiation necessitates high levels of skill acquisition,
rapid reaction time, and organized material readiness. Aspects
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of military training, seamanship, katas, mountain climbing –
even medicine concoction and some cooking – exemplify
aspects of functional precautionary ritual behavior. This minor
caveat aside, B&L have powerfully illuminated underlying
commonalities in ritual behavior.
Ritual: Meaningful or meaningless?
Robert Turner
Wellcome Department of Imaging Neuroscience, Institute of Neurology,
University College London, London WC1 N 3BG, United Kingdom.
r.turner@fil.ion.ucl.ac.uk http://www.fil.ion.ucl.ac.uk/Turner/
Abstract: In conflating opposing meanings of the term “ritual,” arising
from historical Western cultural conflicts regarding church and state,
this target article begs fundamental questions. Its appeals to cognitive
science concepts such as “working memory” are poorly informed and
obfuscate what could have been a far more penetrating and less biased
discussion of stereotyped human action.
In English, it is not unusual for the same word to come to possess
two almost opposite meanings – for example, the word “sanc-
tion” – which require careful distinction. The term “ritual” is
similar, denoting pointless actions and also those with great
meaning for participants. Boyer & Lienard (B&L) (and Cosmides
and Tooby, whom they acknowledge as inspirations for this
study) seem to have been foxed by this etymological quirk. Other-
wise, their use of the term “ritual” to refer simultaneously to both
opposite meanings might be regarded as disingenuous.
Much ethnography has been devoted to teasing out authentic
interpretations of the rituals that are found universally in every
culture (even those of university academics). Cultural anthropol-
ogists’ definitions of the term “ritual” are indeed vague, for excel-
lent reasons. Because the meanings of rituals are generally deeply
embedded in the local network of social institutions and collec-
tive representations, which are to a large extent taken for
granted by participants in a given culture, it is often difficult to
find simple interpretations for specific component actions of
any given ritual. For instance, Sperber (1975) found it quite
impossible to understand why members of the tribe he studied
applied butter to their hair. But absence of evidence is not
evidence of absence, as all good scientists are aware.
B&L have adopted their compatriot Sperber’s rationalistic bias
and are content, at least at the outset of their article, to fully
equate cultural ritual with the pathological and apparently
irrational behaviour of humans suffering from obsessive-
compulsive disorder (OCD), and with the repetitive actions of
small children (who perhaps delight in their freshly-acquired
ability to give order to their personal space and time). But they
do not appear to appreciate that their definition of “ritualized
behavior” as “stereotypy, rigidity, repetition and apparent lack
of rational motivation” (target article, sect. 1), applies precisely
as well to more approved, adult, and non-pathological cultural
forms such as theatre, music, and poetry. It is not at all clear
how these latter forms might relate to “inferred threats to
fitness” arising from a “Hazard-Precaution System” (as the
authors call it, perhaps using the term “system” to distance them-
selves from Pinker’s wholesale misuse of the term “module”; see,
e.g., Pinker 1997). In any case, cultural ritual clearly serves many
purposes, such as worship, dedication, marking a social commit-
ment, enacting a rite of passage, which it would be ridiculous to
associate with inferred threats to fitness. Ritual is often effective
in these contexts because of its dramatic power, bringing together
in a choreographed and synergistic process symbols that have
great resonance in the cultural understanding of its protagonists
(cf. Victor Turner 1969). Perhaps B&L have had no personal
experience of this power, which would explain how easily they
have confused the two opposite senses of the term “ritual.”
It is also important to stress that religious ritual, like other
performative genres, is rarely rigidly repetitive. On the contrary,
it is often tailored to suit the occasion and/or the individuals con-
cerned, particularly in rituals that are intended to be curative.
Ritual experts frequently draw from an extended repertoire of
approved variants, as do Western medical practitioners
(e.g., E. L. B. Turner 1992). The relatively invariant form of
the proceedings can easily be seen to provide an acceptable
context or frame (see Goffman 1974) for social actions, enabling
the participants to interpret them appropriately.
Far from “swamping working memory,” repetitive ritual actions
are typically easily memorized, and thus rapidly become over-
learned, relieving any potential burden on working memory and
allowing a greater focus on the affective and cognitive content
of the ritual context. The reader should be aware that “swamping
working memory,” a favourite phrase of Boyer, is not an accepted
cognitive science concept – perhaps the authors mean “increased
attentional load” (e.g., Lavie 2006). Over-learning is also a vital
aspect of musical performance. Indeed, humans very often rely
on over-learned behaviours, consciously or unconsciously fitting
themselves into predictable and thus interpretable roles. Ritual
action is thus a particularly striking example of role-play.
To argue that such adherence to custom results from a narrowly
defined brain Hazard-Precaution System is question-begging and
has limited explanatory power, like Molie
`
re’s virtus dormitiva.In
my view, this aspect of human social behaviour is supported by a
more “domain-general” brain system (or systems!) for planning,
scenario development, and prediction, which uses Bayesian com-
putational algorithms to imaginatively assess the potential benefits
and costs of a range of possible actions. Cognitive scientists are
familiar with this system as the “central executive” (Baddeley
1990; Norman & Shallice 1980). It is obvious that the ability to
acquire, learn, and represent stereotypical patterns for action
greatly increases the efficiency of such neural computations by
limiting the range of possibilities, and could thus increase
evolutionary fitness. B&L are tendentious in separating out
actions which they happen to believe are “pointless,” as the
products of a special evolutionary module which could give rise
to the pathological behaviour of patients with OCD.
The appeals to brain science made in this target article are also
unconvincing. The authors ascribe a major role in the production
of ritualized behaviour to the anterior cingulate cortex (ACC),
and ascribe the symptoms of OCD to its defective performance.
However, this is one of the largest anatomically defined cortical
areas, and recent studies (e.g., Chein & Schneider 2005) show
that regions within it support a wide variety of functions, such
as domain-general learning, emotional response, placebo effect,
and internally directed attention. While indeed part of the sub-
genual ACC might possibly support the postulated Hazard-
Precaution System (Van Laere et al. 2006), this area has also
been firmly implicated in mood disorder (Mayberg et al. 2005).
The functional anatomy of the ACC is an area of intensive
research, and the authors have reached premature conclusions.
Ultimately, B&L reveal their disdain for what quite clearly
gives most of us our major motivation, delight, and satisfaction –
participation in social rituals such as weddings, funerals, christen-
ings, sporting occasions, graduations, and other initiation
ceremonies – by referring to them as a “waste of time” (sect.
9.3). Such an elitist viewpoint undermines the credibility of
much of this article.
Ritualized behavior as a domain-general
choice of actions
Hongbin Wang
a
& Paul Bello
b
a
School of Health Information Sciences, University of Texas Health Science
Center at Houston, Houston, TX 77030;
b
Air Force Research Laboratory,
Information Directorate, Rome, NY 13441.
Hongbin.Wang@uth.tmc.edu http://www.shis.uth.tmc.edu
Pello.Bello@rl.af.mil http://www.pbello.com
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Abstract: Although we agree that ritualized behavior is a mystery that
calls out for an explanation, we do not think that the proposed domain-
specific two-component system offers an empirically well-justified and
theoretically parsimonious description of the phenomena. Instead, we
believe that the deployment of domain-general mechanisms based on
choice of actions could also explain the essential features of ritualized
behavior.
Fully recognizing that ritualized behavior manifests itself in
vastly diversified forms, Boyer & Lienard (B&L) have taken a
bold and admirable step in proposing to find a common mechan-
ism that is capable of explaining what they claim to be “core
features” across different manifestations of ritual: from pathology
in obsessive-compulsive disorder (OCD) to routinely invasive
thoughts in adults to various elaborate cultural rituals. Based
on various pieces of neuropsychological evidence that link the
ritualized behavior observed in OCD sufferers to specific brain
pathology in the basal ganglia and cortico-striatal loops, a
domain-specific two-component system account has been
suggested.
While the account seems quite reasonable in the case of OCD
(as well as in other motor and cognitive disorders such as Parkin-
son’s disease), we wonder how far it can be extended to explain
ritualized behavior in more complex personal and cultural
rituals. In particular, we are not fully convinced by the suggestion
that the relatively low-level motor control functions of basal
ganglia are primarily responsible for the higher-level ritualized
behavior demonstrated in various cultural rituals such as reli-
gious ceremonies, ancestor worship, and death rituals. Even
the authors constrain their definition of “ritualized behavior” to
be “a precisely defined way of organizing a limited range of
action” (sect. 1, last para.) (i.e., action ritualization); the gap
between motor control functions and ritualized behavior seems
too wide to be easily filled. Ritualized behavior in various social
scenarios clearly involves more than a failure of motor control,
though it may be manifested by rigid, stereotypic, and aimless
action sequences.
The authors’ proposal for a domain-specific “Hazard Precaution
System” for ritualization is also partially based on their observation
that most, if not all, ritualized actions have to do with dangers,
threats, and hazards that somehow impair individuals’ fitness or
survival. They argue, for example, that “washers” compulsively
seek purity while “checkers” desire security. On their account,
when adequate satiation of these desired states is not perceived
to have been achieved, precautionary actions have to be taken to
correct the situation and from this ritual behavior often arises.
Although intuitively appealing, these arguments are difficult (if
not impossible) to falsify. First, even from an evolutionary point
of view, fitness-related features are quite diversified – food, sex,
and pleasure-seeking, to name a few of many, can all be motivating
forces for certain types of behavior. It seems that those most com-
monly observed ritualized actions, such as “washing” and “check-
ing,” only cover a tiny subset of these features. To adequately link
fitness and ritualized actions, one has to explain this “asymmetry,”
that is, why some types of fitness features (e.g., “purity” for
“washers”) are more important (and thus more commonly ritua-
lized) than others. Second, it seems that there is a conflict in the
authors’ arguments that ritualized actions are often fitness-
driven, on one hand, and goal-demoted, on the other. Seeking
health and security, which arguably motivates ritualization in the
first place, is clearly goal-oriented. The compulsiveness and rigid-
ity demonstrated in ritualized actions may seem senseless on the
surface but may not be so beneath. A theory of ritualization has
to strike a balance between ultimate fitness-seeking and superficial
goal-demotion.
Finally, hazard detection and precaution taking are basic and
general neuropsychological mechanisms. In a certain sense, all
forms of human behavior can be cast as results of this detec-
tion-and-reaction operation. Supplementing this point, many
production rule based cognitive architectures, such as ACT-R
(Anderson & Lebiere 1998) and Soar (Newell 1990), actually
model large domains of human cognitive functions using
domain-general rules that are just condition-action pairs. If we
conceive of conditions as hazard-related features and actions as
precautions plans, these systems, with certain additional con-
straints, seem to be capable of explaining most of the ritualized
behavior mentioned by the authors. In order to claim that
hazard detection and precaution generation are specialized
systems responsible for ritualized actions, one has to explain
why such domain-general mechanisms are insufficient or implau-
sible explanatory devices.
We tend to believe that such domain-general mechanisms are
sufficient and may offer a more parsimonious and flexible account
for ritualization than the domain-specific two-system proposal. A
large body of neuropsychological evidence has suggested that the
human brain be viewed as a holistic modular system – while indi-
vidual modules possess functional specialties embodying rich
cognitive functions, causing behavior to emerge when all
modules are unified in principled and constrained ways (Farah
2000; O’Reilly & Munakata 2000). The difficulty lies in defining
sufficiently rigorous criteria for claiming that some of these
modules are part of our evolutionary inheritance, rather than
using them as convenient explanatory devices when one doesn’t
sufficiently consider other alternatives. A striking example con-
cerns the function of Broca’s area. Whereas it has long been
accepted that Broca’s area is specialized for language, it has
recently been discovered that the area also plays a role in hier-
archical event processing and planning (Koechlin & Jubault
2006). Therefore, it is at least conceivable that contextualized
usage of domain-general mechanisms implicated in reasoning
and making decisions about simple (but survival-necessary)
domains, such as navigating the physical world, could adequately
account for ritualization behaviors without sacrificing parsimony.
In particular, if we accept that human behavior is generally goal-
oriented and that goals are naturally multifaceted due to genetic,
evolutionary, social, and cultural constraints, then it is plausible
to assume that different modules are evolved to emphasize differ-
ent types of goals and therefore value actions differently. When
the choice of actions preferred by different systems differs,
they compete to determine the final decision. Note that this
account has been the essence of reinforcement learning
(Sutton & Barto 1998) and is supported by a body of neuropsy-
chological and neurocomputational studies (Daw et al. 2005;
Sanfey et al. 2003; Wang et al. 2006). Since this account empha-
sizes the role of executive control in choice of actions, it more
closely associates ritualized behavior with the domain-general
functions of executive control rather than domain-specific
mechanisms.
Uncertainty and rituals
Erik Z. Woody
a
and Henry Szechtman
b
a
Department of Psychology, University of Waterloo, Waterloo, Ontario, N2L
3G1, Canada;
b
Department of Psychiatry and Behavioural Neurosciences,
McMaster University, MUMC 4N82, Hamilton, Ontario L8 N 3Z5, Canada.
ewoody@uwaterloo.ca
http://www.psychology.uwaterloo.ca/people/faculty/ewoody/
index.html
szechtma@mcmaster.ca http://szechtman.com
Abstract: Boyer & Lienard (B&L) elegantly elaborate the links between
normal motivational systems and psychopathology and address the
evolutionary and cultural context of ritualized behaviors. However,
their model omits a key property of the security-motivation (hazard-
precaution) system, and this property suggests that ritualized behavior
may generate an alternate satiety signal by substituting, in place of
uncertainty, a problem that is verifiably solvable.
In the target article, Boyer & Lienard (B&L) build elegantly
on our theory that absence of negative feedback in a
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security-motivation system generates the symptoms of
obsessive-compulsive disorder (OCD) (Szechtman & Woody
2004; Woody & Szechtman 2005). Their article makes contri-
butions to the important theme of conceptualizing psychopatho-
logical disorders as dysfunctions of motivational systems
(Szechtman & Woody 2006). It does so by elaborating on the
normal properties of the security motivation system. In particu-
lar, the authors address several important issues, including the
evolutionary context of potential danger cues and relevant
species-typical behaviors, the developmental and cultural
origins of relevant variations in normal behavior, and the
importance of learning and cognitive processes in elaborating
the workings of the motivational system.
The authors frame their article with the intriguing question,
“Why ritualized behavior?” From our perspective, a crucial
part of the answer stems from what we consider to be a key prop-
erty of the security motivation system, but one that was not fea-
tured in the authors’ interpretation of this system. Namely, the
problem addressed by the security motivation system is potential
threat, and this problem is inherently open-ended in the follow-
ing sense: Once the system is activated, there are no stimuli in the
external world that provide unequivocal assurance that potential
danger is absent. In fact, it is logically impossible to demonstrate
that there is no potential danger. Hence, the external environ-
ment cannot provide cues for terminating the activity of the
security motivation system. It is for this reason that we proposed
that the system relies on the performance of security-related
behavior itself to provide a satiety signal (which we termed yeda-
sentience) as feedback to shut down the system.
The problem of potential threat is also open-ended in the
sense that it concerns the prospect of future events, which are
inherently uncertain. The issue of uncertainty provides a per-
spective on the reasons for ritualization that contrasts with
those advanced in the target article. In particular, rather than
serving to demote goals and swamp working memory, as empha-
sized by the authors, ritualized behavior may serve to substitute a
clearly defined, closed-ended task for the uncertain, open-ended
problem of potential threat. A crucial aspect of ritualized beha-
vior is that the question of whether it was performed “just
right” is logically answerable, because there are clearly defined
rules governing performance of the behavior. Working memory
is fully engaged to make sure the behavior is being done cor-
rectly, accounting for the high level of concentration during the
ritual. In essence, when security-related behaviors do not
readily generate the satiety signal in the usual fashion, ritualized
behavior may substitute a goal that is verifiably solvable, and
thereby generate a substitute satiety signal.
What empirical tests would differentiate the view we are
advancing from the authors’ interpretation of ritualized beha-
vior? If the function of ritualized behavior is to swamp working
memory, then deviations from the ritual should not reduce the
effectiveness of the ritual or interrupt its flow. In contrast, if
ritualized behavior functions to generate a “just right” satiety
signal (yedasentience), then deviations from the ritual should
interfere with its effectiveness and provoke starting over from
the beginning.
The issue of uncertainty inherent in managing potential danger
raises some unique challenges for any organism. One important
challenge is how much time to allot to security-related behavior
rather than to other survival-related activities. This trade-off
admits of no straightforward solution, because it is always poss-
ible that further investment in security-related behavior would
have been worthwhile, given future events. And yet, an over-
investment in security-related activity may deplete resources
necessary to cope with danger when actual danger does materia-
lize. For example, consider a grazing animal. The more time it
spends being vigilant for potential predators, the less time it
has to graze and nourish itself (Mooring et al. 2004). Paradoxi-
cally, if it over-invests in vigilance, it may be insufficiently
nourished to cope when real danger does materialize.
Humans are faced with similar uncertainties and a similar
trade-off in the allocation of time and resources to being vigilant
for potential dangers versus engaging in other survival-related
endeavors. Although a rational analysis of potential dangers
would take account of their probabilities, our natural, intuitive
evaluations are quite different from this (Kahneman et al.
1982). For example, according to Suskind (2006, p. 62), Vice-Pre-
sident Cheney articulated the position that potential threats,
rather than being evaluated on the basis of “our analysis, or
finding a preponderance of evidence,” should instead be evalu-
ated according to a one-percent doctrine: If there is a one
percent chance of the reality of the threat, “we have to treat it
as a certainty in terms of our response.” In essence, if the prob-
ability of the threat is more than zero, we need to respond as if it
were a certainty. Such a doctrine seems to be a misappropriation
of the security motivation system, in the sense that it indicates we
should act, once the system is activated, as if the danger were real
rather than potential.
It is a trap to seek a sure answer to the question of the absence
of potential danger. Nonetheless, in the face of stimuli suggesting
potential threat, the security motivation system is readily acti-
vated. In this context, we would propose that rituals are more
important than B&L suggest in their summary characterization
of them as an “occasional byproduct,” involving a “waste of
time and resources” (sect. 9.3, Epilogue). Rather, rituals, both
individual and collective, may serve a necessary role in limiting
counterproductive vigilance toward potential threats and provid-
ing closure in response to a security-motivation-driven focus on
unresolvable uncertainty. We need rituals, even today. More-
over, this potential usefulness of rituals lends considerable
importance to further research on the issues advanced in the
target article.
Authors’ Response
Precaution systems and ritualized behavior
Pascal Boyer
a
and Pierre Lie
´
nard
b
a
Departments of Psychology and Anthropology, Washington University in St.
Louis, St. Louis, MO 63130;
b
Department of Psychology, Washington
University in St. Louis, St. Louis, MO 63130.
pboyer@artsci.wustl.edu http://artsci.wustl.edu/ pboyer
plienard@artsci.wustl.edu http://artsci.wustl.edu/ plienard
Abstract: In reply to commentary on our target article, we
supply further evidence and hypotheses in the description of
ritualized behaviors in humans. Reactions to indirect fitness
threats probably activate specialized precaution systems rather
than a unified form of danger-avoidance or causal reasoning.
Impairment of precaution systems may be present in
pathologies other than obsessive-compulsive disorder (OCD),
autism in particular. Ritualized behavior is attention-grabbing
enough to be culturally transmitted whether or not it is
associated with group identity, cohesion, or with any other
social aspect of collective ceremonies.
R1. Introduction
Apart from uncertainties caused by the word “ritual,” most
commentators provided useful suggestions and much-
needed additions to our theory of ritualized behavior on
several fronts, in particular with regard to the compu-
tational and neural requirements of a hazard-management
system; the process of ritualization in patients; the
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BEHAVIORAL AND BRAIN SCIENCES (2006) 29:6 41

question of a possible comparison between ritualized
behavior in obsessive-compulsive disorder (OCD) and in
other pathologies; and the dynamics of cultural cer-
emonies that include ritualized behavior. We discuss
each of these themes in turn.
R2. Why no theory of “rituals”?
From the outset, we knew that it would be of some import-
ance to characterize in the most precise terms the domain
of behavior we were trying to explain in the target article.
This is why we clearly stated (sect. 1 of the target article)
that our model was not at all about the vague category of
“rituals” but about “ritualized behavior,” a precisely ident-
ified form of behavior. It is not too uncommon in empirical
research programs to abandon ordinary language and create
terms that cut across its common categories. So we thought
that particular move should be unproblematic – especially
given how heavily, explicitly, and repeatedly we labored
the point. But the lure of ordinary language is powerful,
perhaps irresistible, together with the illusion that its
categories must correspond to genuine kinds of objects in
the world. This may explain why, for instance, Turner
sets great store by the etymology of the word “ritual,” admit-
tedly a topic of immense interest, although perhaps not for
us as we tried to explain behavior. Also, Hageman and
Turner chide us for saying that (cultural) rituals are mean-
ingless, while Merker, Hageman,andFoss are appalled
by the notion that all rituals are about fear and anxiety.
But, again, we did not make any claims about “rituals.”
We do not even believe it is possible to say anything specific
and explanatory about this vague and confusing category.
Let us just reiterate, then, that “ritual” is a category we
can and should dispense with. Instead, we chose to focus
on a set of behaviors characterized by goal-demotion,
scriptedness, redundancy, and compulsion. These beha-
viors may or may not be present in any particular situation
that we want to call “ritual.” What matters to us is why
ritualized behavior is compelling and intuitively natural,
why it appears at particular points in typical child develop-
ment, why it becomes pathologically inflated in some con-
ditions, and, most important, why it centers around
recurrent themes such as contagion-contamination,
assault-predation, and coalitional psychology. Whether a
model of this intriguing phenomenon squares with stan-
dard or historical understandings of the word “ritual” is a
question that can be safely ignored, or left to the philo-
logically minded.
R3. The functional logic of hazard-management
The Hazard-Precaution model starts with the assumption
that indirect threats to fitness create a specific adaptive
problem: (1) they are quite diverse – as Eilam and
others point out, it is difficult to see where such threats
begin and end; (2) there is no straightforward feedback
demonstrating that a threat has been removed, as
Woody & Szechtman point out, since it is in the nature
of such threats that they are not directly observable;
(3) appropriate measures cannot be mapped one-to-one
on to physically different classes of threats, since each of
the latter may require very different precautions
depending on the situation, as Tooby & Cosmides
emphasize. The cognitive systems underpinning such
appropriate responses must be (a) smart and (b) special-
ized, two points that we should emphasize here.
The responses should be smart. In our view, precaution-
ary behavior requires complex computation rather than
simply a collection of “instincts” (in the sense of straight-
forward, unsophisticated reactions to restricted classes of
stimuli) as Behrendt suggests. Avoiding charging preda-
tors may require a unique response, but avoiding potential
detection by predators requires context-dependent
measures. The same applies, a fortiori, to more complex
sources of fitness-threats like contaminated substances or
social threats.
The responses should be specialized. It is a consequence
of their ecology and fitness effects. A distinction between
specific precautions systems may be necessary, as they
may have different learning logics and calibration processes
during cognitive development. For instance, there seems to
be in humans a general preference for open landscapes with
plenty of potential refuge and escape routes but also good
visibility, which may be interpreted as an evolved precau-
tion against predators (Orians & Heerwagen 1992; Silver-
man & Choi 2005). There is also a general distaste for
festering meats, most probably as a prevention against
pathogen ingestion (Fessler 2002; Fessler & Navarrete
2003b). We would assume that these two forms of precau-
tionary processes are handled by distinct specific systems,
which orient attention to different cues, trigger specific
reactions, and allow learning of associated aspects of situ-
ations in different ways. More generally, precautionary
behaviors probably correspond to the operation of a
variety of systems geared to such special threats as, for
example, predation by large animals, assault by conspecifics,
social exclusion and status-loss, contamination, and others
(we are obviously in no position at this stage to determine
the exact contents of this “catalogue”). These different
systems have different input formats, follow inferential
principles, and produce different outputs.
So, to reformulate what may have been ambiguous in the
target article, we did not assume that one should expect to
find a unique, integrated Precaution-System in the cognitive
architecture of our species. We use the term “precaution
system” in the same general way as one would talk about a
“mating preference system” or a “foraging system,” without
specific presumptions as to the diverse neuro-cognitive
systems that may support such large functions.
As Tooby & Cosmides emphasize, it may make sense
to start by considering two encompassing repertoires, of
all represented hazards and all represented counter-
measures, respectively. But the role of specific inference
systems is to establish the particular connections
between these repertoires. Functional diversity may be
relevant to explaining differences in the extent to which
precaution systems are flexible, context-dependent, and
open to cultural input. In particular, while some systems
seem to take environmental cues as input (e.g., a position
in a landscape is intuitively perceived as protected or vul-
nerable), others require vast amounts of calibration to
local conditions or norms (e.g., preserving friendships
and coalitions).
Importantly, as Tooby & Cosmides point out, each
domain of threat is cognitively defined. That is, there are
no definite physical features that would necessarily mark
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off social exclusion threats from assault threats. It is only
by interpreting accessible information in a specific way
that the organism can identify a particular situation as an
example of the former or latter kinds of threat. So the
different precaution systems are not specialized in phys-
ically distinct types of situations, but in types of situations
that represent different kinds of threat and require differ-
ent appropriate counter-measures for agents at specific
stages of their development and belonging to specific
social categories. As such we should expect systematic vari-
ations in agents’ appraisal, between females and males
(Saad), infants, children, adolescents, and adults. Social
threats, for instance, may consist in a huge variety of utter-
ances, gestures (or in the absence thereof), which only a
long chain of inferences can convert into threats to the
person’s fitness. There may be an infinite number of
ways to diminish someone’s status – ways that, moreover,
differ according to the person’s status – but an efficient
precaution system should associate them with the unique
threat of status-loss. This is why, as Huppert & Cahill
point out, some pathological obsessions and their normal
counterparts often include “modern” themes (e.g., car
accidents), which shows that precaution systems are learn-
ing systems, not situation-driven fixed responses.
Such flexibility and complexity does not entail the oper-
ation of domain-general, all-purpose reasoning processes,
as Wang & Bello propose. In our view, the general
reasoning models proposed are less than compelling
descriptions of the computations required. Production-
rules are only as good as their fit to particular domains
of action, and the problem here is, precisely, that specific
rules are required to nudge organisms towards the most
appropriate precautions. Moreover, our aim was to
model, not the way computational systems in general
could handle information about threats and precaution,
but how specific biological systems actually do it. Evidence
from selective phobias and obsessions, as well as neuro-
functional evidence, suggest specialization rather that
the operation of general reasoning.
R4. Ritualization process and satiation in OCD
The Hazard-Precaution model does not require a strict
demarcation between normal and pathological situations,
contrary to what Foss contends. Indeed, we emphasized
the continuum between normal, sub-clinical, and clinical
manifestations. We are content with the assumption that
ritualization is pathological to the extent that it constitutes
“harmful dysfunction” (Wakefield 1992; 2003), which
implies no straightforward demarcation between pathol-
ogy and the normal case. Also, it is certainly true, as
Huppert & Cahill point out, that ritualized behavior as
described here is not the sole component of OCD sympto-
matology. But our aim was to describe a specific form of
behavior, not to provide a unified account of “OCD” as a
clinical construct (which may be a futile pursuit in any
case). However, these confusions may result from our
own description, as we did not specify to what extend
ritualized behaviors could be expected as outcome of the
activation of precaution systems.
The main point in the model is that precaution systems
trigger particular, species-specific, and contextually appro-
priate precautionary behaviors. Among these could be
included a great many intrusive thoughts and other appar-
ently “irrational” manifestations common in non-clinical
populations (Rachman & de Silva 1978). In general, these
behaviors span the entire range from elementary actions
to highly scripted precautionary sequences. Humans
perform many precautionary behaviors on account of the
socially transmitted information that such behaviors are
appropriate (e.g., burning the sheets and clothes of infected
patients), and they often take care to perform these actions
in the precise way prescribed. People do not care to modify
the established recipes, either because it is simply efficient
to adopt the process without much scrutiny or because
there is no effective means of verification. What marks off
the pathological extreme of precautionary behavior from
intricate precautionary behavior recipe are such features
as the intensity of the compulsion, the anxiety level in
case of non-performance, the compulsion to repeat the pre-
cautionary behaviors, and the extend to which the beha-
vior’s ritualization is felt as intrusive and overbearing.
Obviously, the pathology can include many other responses
to obsessive intrusions, as Huppert & Cahill emphasize.
Those symptoms that do not include ritualized behavior
fall outside the scope of this model. In the case of OCD,
Huppert & Cahill also point out that the compulsive
aspect of ritualized behavior is often driven by hyper-
responsibility, typical in the “thought-action fusion”
observed in many patients (Foa et al. 1993). This last
feature, in precaution-based interpretations, may well be
an outcome rather than a cause of the pathology. To the
extent that precaution systems orient attention and motiv-
ation to potential unwanted effects of own actions, their
impairment might result in such inflated construals of
one’s responsibility.
As we noted above, precautionary behaviors, by their
nature, cannot be terminated by the perception that the
precaution has been effective. You cannot decide
through observation that you have reduced the probability
of an event that never happened, as Eilam , Woody &
Szechtman, Rutherford,andTooby & Cosmides
point out. So it is likely that precaution systems include
some termination mechanism, which limits the fitness
cost of taking excessive precaution. In principle, this may
reside in the precaution scripts themselves as self-
terminating processes. However, it would then be difficult
to understand why OCD patients, who have the same
scripts as normal individuals for precaution actions, still
cannot help repeating the actions.
On the basis of animal models and neuro-psychological
evidence, Szechtman and Woody proposed that a special
circuit provides a satiety signal (Szechtman & Woody
2004) which itself allows a shift to other, non-
precaution-related goals. We did include this in our
model of the neural circuitry involved in ritual, but
perhaps did not do justice to this important component
of the neural processes involved.
This may be why Woody & Szechtman criticize us for
not providing a clear explanation of the use of ritualized
behaviors. They also highlight the contrast between the
respective predictions of their model and ours. In our
view, there is not such a great discrepancy. We accept
the central contention of the Szechtman-Woody (hence-
forth SW) model, that security motivation results (in the
normal case) in behaviors that themselves trigger some
satiety or just-right signal. We also accept that this signal
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is not produced by feedback about the objective elimin-
ation of threats, since the system’s only possible effect is
to reduce the likelihood of threats. We agree that the
absence or weakness of such a signal is a fundamental
piece of the OCD pathology. The real contrast is in the
account of the ritualization process in OCD pathologies.
In the SW model, the ordinary satiety signal is provided
by visceral systems, with input to the limbic system. In
cases of excessive ritualization, SW suggest that there is
displacement, in the sense that a controllable routine is
substituted for the appropriate precaution behaviors, and
the fact that it is accomplished as planned triggers the
satiety signal. The picture we propose is both a refinement
of this idea and a slightly different interpretation.
In our view, the OCD pathology comprises two manifes-
tations that are not usually distinguished in the theoretical
models:
(a) Unstoppable reiteration. The behaviors cannot be
stopped because they are not felt to be completed: for
example, as with patients who incessantly wash their
hands or check their door locks. The action is reiterated
until (usually) some external occurrence forces the
patient to stop, or the satiety signal finally saturates the
appraisal system.
(b) Scripted behavior, for example, tapping several
pieces of furniture with a particular hand in a particular
order, before leaving the room, or washing each body
part a certain number of times in a certain order. In this
case, the action is terminated once the script is properly
performed.
Obviously, the actual symptomatology in most cases
includes many combinations of these two types. But it is
important to keep this distinction in mind, because it
may provide the elements of a (speculative) reconstruction
of the dynamics of ritualization. The evidence suggests
that unstoppable reiteration is generally concentrated on
actions (washing, checking) that are directly relevant
to the security concerns of hazard-management systems,
such as assault-predation and contamination. On the
other hand, at least some of the scripted behaviors
escape from this domain. This is why, for instance, some
patients have rituals in which the prescribed behavior
(e.g., tying one’s shoe laces a certain number of times)
ends up being detached from the usual precautionary
repertoire.
Woody & Szechtman are of course right that one
should explain why patients persist in their rituals and
why performance must be rigid. In our view, this is not
because a substitute satiety signal is provided. Indeed, in
cases of unstoppable reiteration, there is no just-right
feeling (or it exists in an inefficient or too attenuated
form to succeed in decreasing at once the level of
anxiety). A solution might be at hand if we follow Swain
in suggesting the involvement of a reward. What ritualized
behavior produces, on the other hand, seems to be a
specific reward, in the form of a lowered anxiety level,
which we interpreted as the result of making intrusive
thoughts less accessible for the duration of the precaution
system’s activation. So in our view the “substitution” is the
replacement of a (absent or inefficient) just-right or satiety
signal by a positive reward. The latter is associated with
attentional focus on the rules governing exact performance,
and therefore reinforces adherence to these rules. In this
sense, then, we would include in the model decision-
making considerations of the kind suggested by Cavedini
and colleagues, consistent with excessive discounting
observed in many OCD patients (Cavedini et al. 2006).
R5. Comparison of ritualistic pathologies
Since OCD is characterized by compulsive repetition of
apparently unmotivated behaviors, it makes sense to
compare it to other pathologies with unwanted or purpose-
less repetition and stereotypy, notably autism and Gilles de
la Tourette’s syndrome as well as some forms of Parkin-
son’s disease and schizophrenia. This seems all the more
relevant as there is a clear comorbidity between some of
these conditions and OCD.
However, we should introduce a caveat here, concern-
ing the use of such terms as “stereotypic” or “ritualistic”
in the clinical literature. These terms, when used for symp-
tomatologies as diverse as Huntington’s chorea, Tourette’s
syndrome, and OCD, denote vastly different ways of orga-
nizing action. For instance, stereotypy in Tourette’s syn-
drome concerns an idiosyncratic but restricted domain
of gestures and utterances, repeated in various situations,
outside the patient’s control. Autistic repetition also con-
cerns gestures and utterances, but within a larger reper-
toire, and these are not perceived as alien by the patient.
Both Tourette’s syndrome and autism contrast with the
unstoppable behaviors of OCD patients (generally about
evolutionary threats) and their scripted rituals (with high
cognitive control). To bring together these disparate
phenomena under the umbrella term “stereotypy” may
be more misleading than illuminating.
This being said, the problem of stereotypy in autism,
underlined by Kirov, Rothenberger, Roessner, &
Banaschewski (Rothenberger et al.), Benga &
Benga, and Rutherford, is of great interest to models
of OCD. About 90% of adolescent and adult autistic
patients display abnormal repetitive behaviors, both
stereotyped and purposeless (Seltzer et al. 2003). Do
these constitute ritualized behavior in the sense describe
in our model? Autistic stereotyped behavior (and to
some extent similar behaviors in schizophrenia) differs
from typical OCD manifestations: (1) The former are
highly variable (all sorts of gestures or movements are
used) rather than concentrated (on such themes as check-
ing and cleaning). (2) They are non-motivated (the subject
is not aware of any reason for acting stereotypically) rather
than motivated (e.g., to prevent accidents or disasters).
And, (3) as we discuss further on in this response,
though the autistic patient might often be motivated to
rehearse precise sets of acts in particular situations felt
as threatening or challenging, behaviors and threats
seem not to be conceptually linked in autism, whereas
the linkage is more often than not the case in OCD.
Despite these differences, it makes sense to notice the
overlap in the compulsion and repetition and to try and
make sense of its possible neural correlates in both
disorders.
This is difficult because the neural underpinnings of the
autism spectrum are much less circumscribed than those
of OCD. In terms of anatomical differences, structural
imaging has shown differences between autistic patients
and controls in the orbitofrontal cortex (Carper & Courch-
esne 2000; 2005) and in the cerebellum (Allen et al. 2004).
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Functional differences are also numerous, from the
orbitofrontal-amygdala connection (Bachevalier & Love-
land 2006) and the activation of the Broca and Wernicke
language areas (Harris et al. 2006), to more clearly social
circuits like medial prefrontal areas (Frith 1996; Happe
et al. 1996) and superior temporal sulcus (STS) (Pelphrey
et al. 2005). That functional imaging finds so many specific
activations in autism is not surprising as the condition
typically develops from infancy and therefore affects the
overall brain development. In comparison, OCD is often
a late developing condition in a partly- or fully-formed
brain.
Despite all this, the comparison is highly informative.
There are relevant differences between autistic patients
and controls in caudate volumes (Sears et al. 1999), as
well as hemispheric differences in the caudate in patients
(Hollander et al. 2005). Furthermore, the divergence from
controls in basal ganglia volume correlates with the sever-
ity of stereotypic behavior (Hollander et al. 2005). Specific
alteration of the striatum would be consistent with stereo-
typy symptoms. This would suggest that part of the typical
impairments associated with autism might consist in a
similar failure to reach closure after performance of
particular actions.
There may be deeper similarities, too. The evidence
suggests that some aspects of autistic stereotypy may be
very close to an impairment of security systems. Benga
&Bengastate that in autism rituals seem to be per-
formed without any clear connection to threat avoidance.
In terms of conceptual content, it seems indeed that beha-
viors and threats are not linked. Note, however, that
stereotyped behavior in many autistic patients is triggered
or intensified in anxiogenic situations, such as the pre-
sence of strangers or forced social interaction (Ahearn
et al. 2003). Systematic studies of the onset of stereotypy
show that it generally follows the occurrence of an aver-
sive stimulus, and the offset correlates with appearance
of attractive stimuli (Gal et al. 2002). Also, one of the
major symptoms of autism is reduced exploration of the
environment, correlated with restricted growth in particu-
lar cortical structures and the cerebellum (Pierce &
Courchesne 2001). This would suggest that, for the autistic
patient, at least a subset of the stereotypy symptoms are
proximally triggered by situations we identified as typical
of indirect fitness threats: the presence of strangers, and
the need to explore one’s environments beyond familiar
confines. This certainly does not contribute to an expla-
nation of autism, but may help clarify the true and the
misleading similarities.
In this view, then, stereotypy may be a specific distor-
tion of behavior that may or may not be associated with
the other features typical of OCD. This also makes it
easier to understand the presence of stereotypy in other
animal species. Similar pathologies are observed in
animals, especially in caged animals that develop stereoty-
pic and purposeless behaviors. One interesting point is
that these behaviors are invariable taken from the
normal range of (predatory, exploratory, sexual, precau-
tionary) behavior typical of the species. Second, the
appearance and severity of the symptoms depend on
external factors. For instance, stereotypy is greatly
reduced when caged animals are provided with security
cues (a covered place out of sight) and with later
weaning (in lab rats) (Wurbel et al. 1998).
R6. Ritualized behavior and cultural material
Many commentators focused on our description of
ritualized behavior in the context of what are generally
called collective ceremonies or rituals. Since this was the
least-developed part of the model, we welcome the oppor-
tunity to make it more specific. First, we must reiterate
that the model is not about “cultural rituals” in general,
for the same reason that it is not about “rituals” in
general, as explained earlier. According to Hageman,
and to some extent by Alcorta & Sosis and Merker, the
model proposed carries the assumption that collective
ceremonies (to use a fairly neutral term) in general
consist in ritualized behavior. But we are only concerned
with the occurrence of ritualized behavior, its effects,
and its conditions of transmission.
Now, one feature of ritualized behavior is goal-demotion,
a disconnection between action-sequences and goal-
representations. To the extent that ceremonies include
ritualized behavior, they include actions for which an
overall goal can be formulated but without the hierarchy
of sub-goals that usually accompany parts of the action
(Zacks & Tversky 2001). While a sequence of actions is
associated with a goal, its components or sub-actions are
not related to sub-goals. Consider a typical blessing ritual
among the Turkana of Eastern Africa, in which the elders
smear chyme on the bodies of juniors (Lie
´
nard & Boyer
2006). By such smearing elders are said to bestow their pro-
tection unto the young men. But why would the operation
have to follow a very specific and precise sequence (ritua-
lized behavior) to make that person safer? The overall
goal, to protect a person, is not accompanied by sub-goals
that would correspond to each of the sub-actions required,
namely smearing the forehead first, then the shoulders and
the chest repeatedly, then plucking a small quantity of
chyme between the big toe and the next toe. The overall
goal of the ceremony does not explain why all this should
be precisely scripted and rigidly performed. Nor will it be
of much use, as most anthropologists know, to invoke the
idiosyncratic rationalizations for ritual sequences – rationa-
lizations that people in small-scale societies sometimes
provide after much prodding – or the literate theological
justifications produced by literate theologians. These
justification and rationalizations are fascinating cultural cre-
ations, but they do not explain the scriptedness and rigidity
which are our object.
Goal-demotion is difficult to understand and may easily
lend itself to misinterpretation, if one tries to frame it
within everyday categories. For instance, Turner
seemed distressed by our alleged description of collective
rituals as “meaningless,” apparently under the influence of
our “compatriot” [sic] Dan Sperber. This would be very
bad indeed. But we certainly eschew any claims about
“meaning” or its absence – the sort of issues we would
rather leave to professional philosophers. To ask whether
any action has “meaning” or not seems to us even more
nebulous than asking whether or not the action belongs
to a “ritual.” What people understand by the “meaning”
of actions is so unconstrained that participants in cer-
emonies can state either that their actions are extremely
meaningful (Bell 1992), or that they are utterly meaning-
less (Humphrey & Laidlaw 1993); and both can be right,
as it is unclear what these claims amount to in terms of
cognitive processes, the object of our model.
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Features of ritualized behavior include not just goal-
demotion and compulsion, but also internal redundancy
and rigidity in repetition. In our view, the co-presence of
these different features suggests a specific way of processing
action-representations. This is why we would resist analo-
gies with other forms of behavior in which we find, singly,
either rigidity, or goal-demotion, or other features. For
instance, as Fessler points out, many recipe-like behaviors
would seem to show goal-demotion. True, most people who
follow long cooking recipes may do so without representing
the particular goals achieved by each step of the recipes.
This might count as goal-demotion, but the comparison
between cooking and ritualized behavior is not very infor-
mative, as it does not say much about the crucial differ-
ences: the presence of compulsion, rigidity and internal
redundancy in the latter, but not in the former.
This is also why we beg to differ from Fessler’s tempt-
ing suggestion that most cultural ceremonies may be
founded on “magical” associations. The anthropological
evidence does suggest that many ceremonies do trigger
some spurious causal associations. That is, some action is
presented and its result is assumed to obtain. Fessler
sees this as a fundamental feature of ritualized action.
This would suggest an alternative to our model. In that
view, people would be likely to represent spurious causa-
tion for uncertain outcomes, and act accordingly (in a
“magical” way). The presence of precaution themes
would be only a consequence of that process, unsurprising
since precautionary thinking is itself generally based on
imagined (if not imaginary) causation. However, a
problem for that view is to explain why the spurious associ-
ations represented should invariably center on the themes
of predation, attack, social threat, and contagion.
From our point of view, it seems more parsimonious to
see the “magical” flavor of many ceremonies as a predict-
able consequence of the activation of precaution systems,
in itself triggered by precaution themes (invisible danger,
for instance). Since precaution systems always combine
the representation of a distant threat with the represen-
tation of a preventative action, they necessarily suggest
courses of action for which there is no easy demonstration
of efficacy. You cannot demonstrate that the absence of
predator attacks was caused by your camouflage, since
the former is a null effect, as it were.
This goes to the heart of the distinction between
“rituals,” a loosely organized category of actions, situations,
and behaviors, and the specific phenomenon of ritualized
behavior that we described in our model. Note that ritua-
lized behaviors can be found outside of the realm of cul-
tural ritual, for example, in sport, as a way of alleviating
anxiety prior to a competition, as Jackson & Masters
propose. Interactions that comprise ritualized behavior
may also include all sorts of other phenomena. Indeed,
some forms of cultural transmission may easily piggyback
on the attention-grabbing potential of ritualized behavior,
and even share some features with it. As Pyysia
¨
inen
points out, the effects of ritualized behavior on working
memory may be found in a whole variety of techniques,
including some forms of meditation and mysticism. We
certainly concur that the cultural effects of ritualized beha-
vior – for instance, enhancing the salience of particular
associations, or making particular events memorable if
not explicable – are usually accompanied by a host of
other manipulations of mental processes, from music to
dancing to alterations of consciousness. These, however,
are secondary from the point of view of our discussion in
the target article and here: that is, to provide an expla-
nation for the recurrence of ritualized behavior. The fact
that ritualized behavior is associated with, for example,
magical claims, or hierarchy displays, or the reinforcement
of ethnic affiliation, does not explain the compelling nature
and rigidity of the ritualized behavior itself.
Our model suggests that ritualization is really diametri-
cal to routinization. In actual ceremonies, one is bound to
find both highly routinized and highly ritualized behavior.
The Precaution model also suggests that, inasmuch as
there is ritualized behavior in collective ceremonies, one
would find activation of precaution systems. Now, as
McCauley points out, the commitment of some partici-
pants in most ceremonies or of most participants in
some of them is minimal. This entails that, as far as
those participants are concerned, the sequence of beha-
vior does not constitute ritualized behavior as defined
here, and is therefore outside the scope of this model.
For that same reason, the model does not entail that col-
lective ceremonies in general are about “anxiety” or “pre-
caution,” as Foss and Turner imagined. Many forms of
collective action are indeed a source of innocent merri-
ment as much as anguished precaution. But that is
clearly irrelevant. What our model implies, in a more
precise manner, is that, inasmuch as there is ritualized
behavior in rituals and ceremonies, it is liable to activate
precaution systems in at least some of the participants,
and thereby enjoy some transmission advantage.
This is intrinsically an epidemiological claim (Sperber
1996). We are not making claims about the “origins” of
particular cultural institutions or the ultimate “reason”
why people perform ceremonies – indeed we are not
sure that these questions make much sense. We are only
considering transmission, and arguing that transmission
is intrinsically entropic, as it depends on imperfect acqui-
sition and communication processes. Against this, the pre-
sence of highly recurrent features in many collective
ceremonies (Dulaney & Fiske 1994) requires an
explanation.
We proposed that ceremonies that include such precau-
tion-relevant themes would be more likely to be trans-
mitted than those that do not. Also, as Orrock points
out, an important effect of ritualized behavior may be to
allow recalibration of defenses against indirect threats,
which is why we should and do observe connections
between particular points in the life-cycle and particular
forms of individual and collective ritualization. As Schip-
per, Easto n, & Shackelford (Schi pper et al.) suggest,
the specific stage of the life-cycle at which an agent is
indeed predicts that agent’s sensitivity to specific pro-
blems. All this, obviously, is not the same as saying that
“low-level motor control functions of basal ganglia are pri-
marily responsible for higher-level ritualized behavior
demonstrated in various cultural rituals,” a claim that
Wang & Bello find odd – perhaps because it could not
be found in the target article.
R7. Ritualized behavior as adaptation
A central question is whether evolved mental capacities
are specifically geared to the production of collective
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action with ritualized behavior. As we said in the target
article, most functionalist accounts of ritualized behavior
so far flounder because they provide an account of social
or cognitive outcomes that would be optimally provided
without scripted, rigid, goal-demoted, et cetera, action-
sequences. If “rituals” convey religious knowledge or
maintain social identity, many non-ritual forms of inter-
action do that just as well.
By contrast, Merker and Alcorta & Sosis offer a more
refined explanation, centered on the costly nature of many
ceremonies – costly not only in terms of resources but also
in pain and danger – suggesting that a deliberate dimin-
ution of one’s own fitness is the point of the whole exercise.
In this sense human ceremonies could be compared to
various traits and behaviors that impose a handicap on
their bearers and therefore advertise a surplus of fitness
potential (Zahavi & Zahavi 1997). They could be more
precisely defined as a strategic form of costly signaling
(Grafen 1990).
We briefly – perhaps too briefly – discussed this poss-
ible interpretation. We think Merker and Alcorta &
Sosis suggest something both plausible and important,
namely, that some forms of social behavior may constitute
self-imposed fitness-losses, and that we may have evolved
dispositions for identifying such behaviors and interpret-
ing them as paradoxical fitness-signals, according to the
handicap principles (Zahavi & Zahavi 1997). However,
we have reservations on two fronts.
First, the association between ritualized behavior and
costly performances do not explain the features of ritua-
lized behavior. We agree that ritualized behavior may be
co-present with various forms of signaling, including
costly, handicap-based signaling, in a great many social
ceremonies. However, as we said in the target article, a
whole variety of social interaction processes are contin-
gently associated with specific episodes of ritualized beha-
vior in specific groups. That is, it is certainly impossible to
engage in ritualized behavior with other people without, at
the same time, communicating some information about
status, or about commitment, or about conflicts, and so
forth. In our view, however, these processes – including
the occurrence of costly signaling – are not good candi-
dates for a general model of ritualized behavior because
(a) they are not invariably associated with the latter, and
(b) even if they were frequent enough, they would not
explain why the behavior is ritualzed. For example,
blood letting (through penile incisions, for instance) can
be done ritualistically (in the precise sense adopted
here) or matter-of-factly in front of everyone. Both beha-
viors could be conceived of as costly signaling. But this
would not account for the differences between the two
kinds of behavior.
Second, our challenge was to explain why ritualized
behavior is so consistently associated with such themes
as contagion, assault, and other fitness threats. This is
where the association with signaling, even if it was
general, would be of little explanatory help, without
additional specific hypotheses.
We have similar reservations about the various uses of
“ritual” as described in cultural anthropology. For
instance, Alcorta & Sosis are probably right in
suggesting that, in many cases, an outcome of ritualized
behavior is that particular conceptual associations are
strengthened as a result of attention-grabbing experience.
However, we should also note that in many situations of
ritualized behavior, the main focus of possible query
would be the connection between goals and recipes,
and that is precisely what remains obscure to most
participants. Most rituals do not communicate much or
communicate very well, in terms of transmitting unam-
biguous norms or concepts (see reviews in Bloch 1974;
Lawson & McCauley 1990; Lie
´
nard & Boyer 2006;
Sperber 1975; Staal 1990).
R8. Outstanding questions
Our aim was to contribute to an integrated explanation of
ritualized behavior, starting from deep models of neuro-
cognitive function (Szechtman & Woody 2004) and of
hazard-management (Cosmides & Tooby 1999). Although
there has been substantial progress in the neuropsychol-
ogy and neurophysiology of such conditions as OCD,
there remain great lacunae in our understanding of
normal and pathological threat-management. Some of
these uncertainties stem from a lack of relevant evidence,
particularly in the description of OCD (and other con-
ditions’) symptomatology.
First, theoretical models, such as the one put forward in
our target article but also most current interpretations of
ritualization, would require specific descriptions of symp-
tomatic evolution in patients, from the first manifestations
to the clinical presentation observed by the therapist or
neuropsychologist. The paucity of detailed case histories
makes it very difficult to test any claims about the
dynamics of ritualization, which is crucial to validating
models in terms of security-motivation or working
memory processes.
Second, we have only rather vague, impressionistic
descriptions of what we call ritualized or stereotypic beha-
viors in the various pathologies, from Tourette’s syndrome
to OCD, schizophrenia, and autism. As noted above, there
are important differences between purposeless reiterated
gestures, unstoppable goal-directed behaviors, and com-
plexly scripted precautionary measures. But this distinc-
tion is only the beginning. Very few clinical descriptions
provide us with a detailed account of who does what,
when, and how often. A brilliant exception is Eilam ’s
research into the parameters of ritualized behavior in
some OCD patients (Eilam et al. 2006). We consider
that such highly specific ethological descriptions of
patient presentation should constitute a major element
in our understanding of the underlying impairment.
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