In: Causes and Risks for Autism ISBN: 978-1-60456-861-5
Editors: A. C. Giordano et al. © 2009 Nova Science Publishers, Inc.
“No Time Like the Present”:
Time Perception in Autism
Melissa J. Allman*
and Iser G. DeLeon
1 The Kennedy Krieger Institute and Johns Hopkins University
School of Medicine
2 The Kennedy Krieger Institute and Johns Hopkins University
School of Medicine
The terms ‘autism’ and ‘autistic’ derive from the Greek word autos
meaning self. This is appropriate to describing the autistic behavioral
phenotype in which there is a pathological impairment in socialization and
verbal and nonverbal communication, in addition to behavior and interests
that are often highly restricted and repetitive (the triad; American Psychiatric
Association, 1994). The autistic individual often appears isolated, and unable
to make sense of the world around them. They often reveal an inability to
predict and understand the behavior of others, and perceptions of the world
remain fragmented and are not embedded into a coherent pattern or structure.
Time is part of the fundamental intellectual structure in which we make
sense of the events in our lives. ‘Timing and time perception allow us to
unite action sequences and events occurring separately in time, to adapt to
* Address correspondence to: Melissa J. Allman; Department of Behavioral Psychology ; Kennedy
Krieger Institute; 707 N. Broadway; Baltimore, MD 21205
Melissa J. Allman and Iser G. DeLeon
reoccurring situations, and to predicate behavior on what is expected to
occur’. Timing and time perception are essential for adaptation and learning,
memory and attention, cognitive development, and social synchrony and
communication (see Meck, 2003). Firsthand accounts of people with autism
often report a need to adhere to rituals or routines to compensate for a failure
to predict events, and to their disorientation in time. They reveal a general
lack of understanding about the passage of time, and appear stuck in the
present. It is for these reasons that the issue of timing and time perception in
autism is particularly intriguing. We will review empirical evidence that
collectively suggests time perception may be disordered in autism, and
postulate that fundamentally, a disturbed ‘time sense’ may contribute to
features of the autistic behavioral phenotype.
Time is an omnipresent feature of the human experience, and accordingly has
been the subject of enquiry since the dawn of civilization (e.g., Saint Augustine,
397/398 AD) and the advent of modern psychology (e.g., James, 1890; see
Fraisse, 1963 for a review of debate about time perception over 25 centuries).
Time is so fundamental to our understanding of the world that it is difficult to
imagine a world without it. Imagine if you could not represent the length of a
minute, a year, or were unable to anticipate the impending change of a traffic
light, or the length of a movie (how would you know that once started it would
come to an end?). ‘Our capacity to perceive temporal structure and our sensitivity
to time on multifarious scales; from short durations (i.e., milliseconds and
seconds) to long durations (e.g., hours and days), at perceptual, conceptual and
linguistic levels, is central to our adaptive functioning, and all behavior is
ultimately under the control of time’ (Michon & Jackson, 1985). These authors
assert that time “occupies a central position in our cognitive representations of
reality” (1985, p. 3), and time is widely regarded as the most important dimension
by which we make sense of the world (Navon, 1978).
Relatedly, there are anecdotal and clinical reports that individuals with autism
experience difficulty in comprehending the passage of time, and this has a
significant impact upon how they perceive the world (see Boucher, 2001).
“Concepts of time have always puzzled and fascinated philosophers but most
people are born with the ability to understand it in everyday terms. People with
autistic disorders seem to lack this understanding to a degree that is markedly
discrepant with their level of intelligence” (Wing, 1996: 89). Remarkably, very
“No Time Like the Present”: Time Perception in Autism 67
little empirical attention has been paid to examining time perception in autism
(but see Boucher, Pons, Lind & Williams, 2007; Szelag, Kowalska, Galkowski &
Poppel, 2004). This chapter will introduce elements in the typical development of
time perception during infancy and childhood, and will review evidence that
indicates these may be impaired in autistic individuals. It will speculate on how a
disordered ‘time sense’ may contribute to the triad of autistic impairments.
Typical Development of Time Perception During Infancy
Developing an understanding of temporal structure has been postulated to
depend upon any number of ‘time experiences’, a comprehensive discussion of
which is beyond the scope of this chapter (but see Friedman, 1982; Lewkowicz,
1989; 1992; Poppel, 1978). Suffice to say here, that duration, synchrony, order,
and ‘past and present’ appear to be key elements that lay the foundation for the
perception and representation of time. Each of these elements will now be
discussed in relation to autism.
The developmental psychology of time perception postulates that awareness
and knowledge about temporal duration emerges from intrinsic biobehavioral
rhythms and early action (Lewkowicz, 1989). The temporal regulation of
rhythmic stereotypies displayed by infants (see Thelen, 1981) has been postulated
to facilitate their adaptation to the temporal contingencies of their physical and
social environments (Droit & Pouthas, 1992). Furthermore, especially in the early
years, repetitive motor actions may themselves serve to measure the duration of
events. Pouthas (1985) observed that when typically developing 10-24 month olds
were required to withhold responding for a target delay (i.e., 5 s), they did so by
adopting repetitive actions during the interval (i.e., they engaged in body-rocking
or moved around the room in a certain fashion), but in older children between the
ages of 4-7 yrs, manifestations of this ‘behavioral clock’ were significantly
reduced (Pouthas & Jacquet, 1987). It appears that reliance upon motor actions to
estimate duration may be supplanted (during development) by more cognitive
processes. In a similar vein, mentally retarded children aged 6-17 (with an IQ
between 29 & 48) can reproduce a given duration as accurately as typically
developing children aged 3-6 years, if they are allowed to engage in repetitive
Melissa J. Allman and Iser G. DeLeon
behaviors (and have rhythmic structure) during the interval (see Fraisse, 1982).
Perhaps then, a failure to acquire an understanding of duration and temporal
contingencies accounts for the persistence of stereotypic behaviors in autistic
individuals into adult life. This tenet is strengthened by empirical evidence
(Szelag et al., 2004) that high-functioning children with autism (9-16 yrs) are
severely impaired in their ability to reproduce target durations (between 1-5 s)
compared to age-matched typically developing controls. These authors explicitly
attribute such failures to deficits in the autistic internal timing system. An
impaired understanding of duration is also revealed by the autistic “lack of
awareness that an event, once started, will come to an end” (Wing, 1988, p. 88).
Synchrony is considered one of the first features of temporal experience to be
differentiated by an infant (Lewkowicz, 1992). Here, we will refer to two aspects
of synchrony: interactional synchrony (the ability to adapt to a temporal structure
or coordinate with external events), and intermodal synchrony (the ability to
perceive temporal synchrony in events occurring at the same time), both of which
can be acquired during parent/infant interactions. It has been postulated that the
temporal patterning of a parent’s communication toward the infant is the most
important aspect of these interactions for the child, and allows them to acquire an
understanding of temporal expectancies and structure (Stern, Beebe, Jaffe &
Bennet, 1977). An infant’s ability to temporally coordinate his or her behavior
with that of another person is key to preverbal and verbal interactions, in which
turn-taking must be accurately timed (Trevarthen & Aitken, 2001). From birth,
infants are typically able to synchronize with certain aspects of their parents’
communication (Malloch, 1999), and exquisite reciprocal behavioral rhythms and
regularities are observed during parent/infant interactions (for details, see Lester,
Hoffman & Brazelton, 1985). However, asynchronous social coordination (during
these interactions) has been retrospectively observed in 11-month-old autistic
infants (Trevarthen & Daniel, 2005; see also Kubicek, 1980). Moreover, the
discrimination of temporal synchrony between intermodal events (i.e., the sight
and sound of the parent’s speech) during parent/infant interactions “may be the
first step in developing a capacity to discriminate more complex and specific
forms of language” (Bebko, Weiss, Demark & Gomez, 2006, p. 96). These
authors report that autistic children (aged 4-6 yrs) reveal atypical responding to
mutimodal temporal asynchrony with language-specific stimuli. Collectively,
“No Time Like the Present”: Time Perception in Autism 69
these findings lend support to the suggestion that an understanding of temporal
synchrony may be impaired in autistic individuals.
Order and ‘Past and Present’
The order of successive or serial events is a fundamental aspect of temporal
structure, and also provides information as to the causal relationships between
events. Harner (1982) asserts that two types of seriation exist. The first is the
relative position of two events on a time continuum (i.e., one event precedes the
other). This form of knowledge about temporal order is likely spared in autism, as
paired-associate learning and linear sequencing of successive items is typically
intact (Kanner, 1943; Minshew, Goldstein & Siegal, 1997) and is commonly
evidenced by echolia, and rote learning for phrases or songs (Boucher, 2001).
This type of ‘temporal stringing’ has been argued to depend upon linear (or
circular) visual representations of temporal order (Friedman, 1990). This is
interesting in relation to autism, as Temple Grandin, one high profile autistic
individual reports “my mind is like a…quick access videotape. But [in order to
remember an aspect of an event] I have to play the whole part—no fast forward”
(Sacks, 1995, p. 269). However “it seems that people with autistic disorders have
severe problems coping with sequential events that have no independent, concrete
existence” (Wing, 1988, p. 89), so a child may have difficulty understanding the
concepts of ‘yesterday’, and ‘tomorrow’, unless these are concretized by showing
them a calendar and the relevant dates. This is evidenced by the popularity and
success of picture schedules (of temporally sequenced events) in the training and
treatment of children with autism (e.g., Lalli, Casey, Goh & Merlino, 1994;
MacDuff, Krantz & McClannahan, 1993). The second aspect of seriation is the
position of events in the overall time continuum; although two events will
maintain a consistent relation to one another, their inclusion in the before or after;
or past, present and future categories of experience is transitory (e.g., tomorrow
becomes yesterday). A sensitivity to this more complex form of sequential
structure is considered crucial for action knowledge, object use, drawing
inferences from others actions, and planning one’s own behavior (Baldwin, Baird,
Saylor & Clark, 2001; Zalla, Labruyere & Georgieff, 2006). This type of
hierarchical temporal coding is likely deficient in autism (see Boucher, 2001, p.
113). For instance, it has recently been reported (Boucher et al, 2007) that
children with autism (7-16 yrs) reveal marked impairments in diachronic thought.
That is, they are unable to i) think about past or future stages of current situation,
Melissa J. Allman and Iser G. DeLeon
ii) understand that things can change or evolve over time but are still the same
thing, and iii) that successive events are part of a unitary process (see also
How a Disorder of Time Perception May Contribute
to the Autistic Behavioral Phenotype
It is difficult to know with any degree of certainty how a disordered sense of
time might impact behavioral and cognitive function, but is easy to speculate.
That the products of this speculation so closely resemble features of the autistic
behavioral phenotype is particularly striking.
Restricted and Repetitive Behaviors
Janet (1928) noted that one of our earliest experiences with time (duration)
arises during periods of waiting, when there is an imposed delay between our
desires and their satisfaction. An inability to wait represents a deficit in linking
the passage of time with ongoing activities, and is a common problem for autistic
children and adults (Wing, 1988). “Impatience is common in all young children
but in people with autistic disorders it can continue for years, even into adult life”
(1988, p. 88). Recall that in one study (Pouthas, 1985), waiting in young children
was facilitated by their adoption of repetitive behaviors (e.g., stereotypies) that
functioned to parse the delay interval. That stereotypies can function as a
‘behavioral clock’, suggests that a failure to understand the passage of time
(duration) may account for the persistence of certain repetitive behaviors in
autism. Stereotypies are typically produced in repeating cycles, and may be
seperated by (often short) intervals in time—continually measuring intervals in a
repeating cycle requires less attentional resources (Lewis & Miall, 2003), and so
repetitive motor behaviors may be a particularly effective time-parsing stratergy
for autistic individuals, and might function to concretize and reduce the stressor
of an imposed disorientation in time. Peeters and Gillberg (1999, p. 87) report that
“most people with autism feel lost in a sea of time…they will often try to develop
routines and rituals by way of compensation. They want all activities to be
undertaken in the same sequence every day…and if the sequence of activities
changes on a certain day, then they have behavior problems” [which can include
rhythmic lower-order motor behaviors, e.g., head-banging, self-injury]. To
“No Time Like the Present”: Time Perception in Autism 71
reiterate the main point here, an autistic impairment in the perception of duration
may be compensated for by the production of repetitive motor behaviors (such
collateral behaviors are often observed during superior temporal performance in
animal studies), and an overreliance upon intact abilities, such as sequencing and
order, and the stringing together of temporal units of perseveration or habits.
One very interesting possibility was considered by Boucher (2001). In her
own words, “try to imagine periods of time longer than the lifetime of the
universe…in fact, one cannot imagine a period of time longer than the lifetime of
the universe except by thinking of a temporal succession of universes with
cumulative lifetimes” (2001, p. 121). She suggests that there may be a close
correspondence between the length (and complexity) of repeating behavioral units
(e.g., stereotypies, rituals) and the ability to imagine extended time frames in
autism. As shorter and less complex stereotypies are usually observed with lower-
functioning autistic individuals, and more complex, rigid routines are observed in
those who are higher functioning, it follows that the ability to perceive duration
might account for quantitative and qualitative differences in repetitive behaviors
across the autistic spectrum (Boucher, 2001).
Language and Social Communication
Selective impairments in the autistic child’s’ ability to temporally coordinate
to their social environment and to represent the temporal structure of their social
and physical world, may explain the lack of interest in social interaction from the
first year of life which parents of autistic children typically report (Wing, 1988).
It may also contribute to these individuals retreating into their own ‘inner world’
(aloofness), and explain their preoccupation for repeating or rhythmical sensory
stimulation (e.g., Grandin, 2005). Autistic deficits in acquiring knowledge from
these early ‘time experiences’ (e.g., synchrony, duration) might produce a cascade
of other autistic deficits (a full discussion of which is beyond the scope of this
chapter). For example, we have seen that “in speech perception, temporal factors
such as synchrony, duration, rate and rhythmic structure play an important role in
the integration of the visible and audible aspects of the signal” (Lewkowicz,
1992, p. 34). Generative language production and comprehension is heavily
dependent upon a multitude of temporal competencies, and with its immanent
references to time (e.g., past, present and future tenses), language may become an
irreconcilable code for an individual who lacks temporal fluency, as we postulate
Melissa J. Allman and Iser G. DeLeon
The Autistic Perceptual Experience
Our subjective experience of duration is fallible, and can be influenced by a
variety of factors (such as the content of the interval, drugs, and body
temperature, e.g., see Meck, 2003). The popular phrase ‘time flies when you’re
having fun’ is testament to this quality of duration perception. There is also a
debated phenomena known as ‘time dilation’. This refers to the sensation that
time can appear to slow down, or pass by in slow motion (particularly during
periods of heightened arousal). When Alice fell down the rabbit hole at the
beginning of her adventures in Wonderland, “either the well was very deep, or
she fell very slowly, for she had plenty of time as she went down to look about
her, and to wonder what was going to happen next" (L. Carroll, 1992). We might
be familiar with a similar experience when our car starts to skid off the highway
at speed. This phenomenon of time ‘warping’ is believed to be the product of an
increase in the speed of the internal timing apparatus (and is currently being
investigated by D. M. Eagelman and colleagues). It may be biologically adaptive,
as it appears to produce a hypersensitivity to sensory events, and prompts an
elemental rather than configural processing bias that serves to facilitate decision-
making ability. During these moments, the individual is also ‘stuck’ in the
subjective time present. In light of the fact that autistic individuals appear to
experience qualitative differences in sensory perception (Grandin, 2005) it is
possible that the subjective experience of time is more mercurial to intrinsic
and/or extrinsic variables in people with autism; with the ‘speed’ or function of
the internal timing apparatus being different or more variable in these individuals.
Within this conceptual framework, lower-order rhythmic motor behaviors may
function to regulate and stabalize the subjective perception of duration.
Furthermore, if the perception of duration is anomalous between different sensory
modalities in autism (i.e., visual and auditory; see Penney, Gibbon & Meck,
2000) then this may produce problems with intersensory integration (and
intermodal synchrony), and the binding of external inputs into meaningful
information (e.g., see Brock, Brown, Boucher & Rippon, 2002).
The interest in understanding time perception in normal and patient
populations (including conditions co-morbid with autism) is growing rapidly
“No Time Like the Present”: Time Perception in Autism 73
(e.g., Toplack, Dockstader & Tannock, 2006), yet the paucity of empirical data
relevant to autism is particularly striking (Boucher et al., 2007) given anecdotal
reports that ‘whatever it is that typically developing individuals posses that gives
them a sense of timing we, as individuals with autism certainly lack it’ (Lawson,
2001, p. 43). This chapter, and those studies which it cites, have elucidated how
deficits in the experience of time may contribute to the autistic behavioral
phenotype (the triad; APA, 1994). Pursuing this line of enquiry may enhance our
understanding of this perplexing disorder, and advance extant interventions and
strategies designed to concretize the passage of time for autistic individuals. An
autistic preoccupation with timetables, clocks and calendars is common and may
be particularly useful in helping autistic individuals to understand time (Wing,
1988). For example, it would be of particular interest to examine whether devices
such as the Time Timer™ are effective in reducing repetitive behaviors during
periods of waiting. Given that sensitivity to the temporal parameters of experience
can be evidenced within the first year of life, it may also be worthwhile to
incorporate assessments of temporal competence into early-year studies of at-risk
autistic infants, in the hope that they may provide some predictive power as to
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