ArticlePDF Available

Lateralized Direct and Indirect Semantic Priming Effects in Subjects with Paranormal Experiences and Beliefs

Authors:

Abstract and Figures

The present investigation tested the hypothesis that, as an aspect of schizotypal thinking, the formation of paranormal beliefs was related to spreading activation characteristics within semantic networks. From a larger student population (n = 117) prescreened for paranormal belief, 12 strong believers and 12 strong disbelievers (all women) were invited for a lateralized semantic priming task with directly and indirectly related prime-target pairs. Believers showed stronger indirect (but not direct) semantic priming effects than disbelievers after left (but not right) visual field stimulation, indicating faster appreciation of distant semantic relations specifically by the right hemisphere, reportedly specialized in coarse rather than focused semantic processing. These results are discussed in the light of recent findings in schizophrenic patients with thought disorders. They suggest that a disinhibition with semantic networks may underlie the formation of paranormal belief. The potential usefulness of work with healthy subjects for neuropsychiatric research is stressed.
Content may be subject to copyright.
Original Paper
Psychopathology 2001;34:75–80
Lateralized Direct and Indirect Semantic
Priming Effects in Subjects with
Paranormal Experiences and Beliefs
D. Pizzagalli D. Lehmann P. Brugger
The KEY Institute for Brain-Mind Research, University Hospital of Psychiatry, and Department of Neurology,
University Hospital, Zurich, Switzerland
Dr. Diego Pizzagalli
Laboratory for Affective Neuroscience
Department of Psychology, University of Wisconsin
1202 W. Johnson Street, Madison, WI 53706 (USA)
Tel. +1 608 263 5072, Fax +1 608 265 2875, E-Mail dpizzag@psyphw.psych.wisc.edu
ABC
Fax + 41 61 306 12 34
E-Mail karger@karger.ch
www.karger.com
© 2001 S. Karger AG, Basel
0254–4962/01/0342–0075$17.50/0
Accessible online at:
www.karger.com/journals/psp
Key Words
Associative processing
W (Indirect) semantic priming W
Hemispheric differences W Schizotypy W Paranormal belief
Abstract
The present investigation tested the hypothesis that, as
an aspect of schizotypal thinking, the formation of para-
normal beliefs was related to spreading activation char-
acteristics within semantic networks. From a larger stu-
dent population (n = 117) prescreened for paranormal
belief, 12 strong believers and 12 strong disbelievers (all
women) were invited for a lateralized semantic priming
task with directly and indirectly related prime-target
pairs. Believers showed stronger indirect (but not direct)
semantic priming effects than disbelievers after left (but
not right) visual field stimulation, indicating faster appre-
ciation of distant semantic relations specifically by the
right hemisphere, reportedly specialized in coarse rather
than focused semantic processing. These results are dis-
cussed in the light of recent findings in schizophrenic
patients with thought disorders. They suggest that a dis-
inhibition with semantic networks may underlie the for-
mation of paranormal belief. The potential usefulness of
work with healthy subjects for neuropsychiatric research
is stressed.
Copyright © 2001 S. Karger AG, Basel
Introduction
Inappropriate, ‘loose’ associations have long been con-
sidered a key feature of the language of patients with acute
schizophrenia [1]. It has been suggested that this ‘loosen-
ing’ of associations may be a consequence of a decreased
inhibition of the spreading activation within semantic
networks [2]. Spreading activation theories of the func-
tional architecture of semantic memory [3] assume that
concepts are represented as nodes, and are interconnected
by a network of links along which activation proceeds
automatically. In a properly working cognitive system,
closely related semantic concepts are more strongly inter-
connected with each other than distantly related concepts,
and will be coactivated with a high probability. On the
other hand, in schizophrenia, the activation in these net-
works, rather than spreading from one concept to a neigh-
boring concept in a focused manner, is supposed to pro-
ceed along new links, reaching several widespread, only
loosely interconnected nodes (i.e. associative intrusions
arise; see [4–7] for the electrophysiological and pharmaco-
logical mechanisms involved).
In schizophrenia research, the paradigm of semantic
priming has repeatedly been employed to measure the
‘spread of activation’ within semantic networks. In this
paradigm, subjects are required to decide whether the sec-
ond of two consecutively presented letter strings is a real
word. Semantic priming effects refer to shorter reaction
76
Psychopathology 2001;34:75–80
Pizzagalli/Lehmann/Brugger
times to the second (target) word when it is preceded by a
semantically related (prime) word as compared to a non-
related prime. Compatible with the postulated mecha-
nism of disinhibition, increased semantic priming effects
(‘hyperpriming’) in schizophrenic patients was demon-
strated in some studies [8–13]. However, no hyperprim-
ing was observed in other experiments [14].
More recent studies employed the paradigm of indirect
semantic priming [15] and significantly extended these
results. In this paradigm, prime (e.g. lion) and target
(stripes) words are indirectly related, i.e. they are both
related to a third, mediating concept (tiger or zebra). In
healthy persons, indirect priming effects are smaller than
direct priming effects, a finding which corroborates the
view that the amount of spreading activation is inversely
related to the semantic distance (i.e. the number of asso-
ciative steps) between two concepts [15]. Interestingly,
indirect as compared to direct semantic priming allows a
better monitoring of presence or absence of thought disor-
der in schizophrenic patients [11–13, 16]: whereas pa-
tients with thought disorder treated indirectly related
prime-target pairs as directly related, several control
groups of non-thought-disordered subjects treated them
as unrelated. Taken together, these studies on direct and
indirect semantic priming presented evidence of a faster
and farther-spreading activation in the semantic network
of patients with schizophrenia.
The concept of ‘schizotypy’ proposes the presence of
schizophrenia-like signs in healthy subjects [17, 18].
These include hallucination-like experiences and delu-
sion-like, ‘paranormal’ beliefs [18, 19]. Qualitatively,
there are considerable commonalities in the performances
of schizophrenic and schizotypal individuals on tasks rel-
evant to associative processing [20–23]. For instance, one
recent study employing a verbal fluency task demon-
strated that healthy subjects with a high frequency of
paranormal experiences and beliefs produced a high per-
centage of uncommon word associations [21], a finding
paralleling previous observations in patients with produc-
tive symptoms of schizophrenia [24].
To understand the mechanisms underlying this en-
hanced availability of specifically ‘distant’ associations,
we propose to integrate results from two hitherto uncon-
nected neuropsychological research fields. First, lateral-
ized semantic priming tasks presented evidence for a right
hemisphere (RH) preference for coarse as opposed to
focused semantic analysis [25–28]. Second, as recently
reviewed by Crow [29] and Leonhard and Brugger [30],
one prominent feature of both schizophrenia and schizo-
typy is an absence of a clear dominance of the left hemi-
sphere for linguistic processing. Taken together, these two
observations suggest that a reduced left hemisphere (LH)
participation may favor the emergence of ‘loose’ associa-
tions by a relative overreliance on unfocused activation
within RH semantic network (see [30] for the experimen-
tal evidence).
The present experiment examines spreading activation
processes as a function of the stimulated hemisphere in
subjects differing in their declared belief in paranormal
phenomena. Based on the literature reviewed above, we
predicted that (1) specifically for indirectly related prime-
target pairs, believers show larger semantic priming than
disbelievers, and (2) this effect is more pronounced after
left visual field (LVF)/RH stimulation than after right
visual field (RVF)/LH stimulation.
Method
Subjects
Three hundred and fifty-two undergraduate psychology students
of the University of Zurich were given a 6-item questionnaire assess-
ing belief in and experience of paranormal phenomena (mainly tele-
pathy and precognition) on a 4-point scale (possible score 0–18 [31,
32]). Subjects were also asked about their willingness to participate in
an experiment on ‘neuropsychological and electrophysiological cor-
relates of belief in extrasensory perception’. Among the 117 students
(91 women) returning the questionnaire and indicating their willing-
ness to participate, 12 individuals scoring in the highest 25% of the
questionnaire (‘believers’ 16.3 B 1.2, mean B SD) and 12 scoring in
the lowest 25% (‘disbelievers’ 3.3 B 2.9) were contacted. Since there
were only 5 men among the believers, and we had planned to investi-
gate subjects of one gender only (because gender is a confounding
variable in laterality research; see Beaton [33] for overview), only
women were asked to participate.
All participants were right-handed [34] native Swiss-German
speakers, and had no history of psychiatric or neurological disorders.
Believers and disbelievers did not differ with respect to age (26.3 B
6.2 vs. 26.8 B 4.3 years), handedness score (13.7 B 1.3 vs. 13.2 B
0.6 [34]) and parameters of menstrual cycle (duration 29.3 B 2.9
days vs. 28.3 B 1.2 days; days after last menstruation 16.3 B 7.4 vs.
16.7 B 10.7 [35]). The study was approved by the Ethics Committee
of the University Hospital Zurich, and each subject gave informed
written consent. Subjects received CHF 40.00 for their participation
in the experiment.
Stimuli
All stimuli were letter strings between 3 and 7 characters. There
were 240 prime-target pairs divided into 4 categories of prime-target
relations. While all primes were nouns (n = 240), the target was either
a directly related noun (n = 40), an indirectly related noun (n = 40),
an unrelated noun (n = 40) or a pronounceable nonword (n = 120).
Several word pairs of the first two categories were selected from prior
priming experiments [15, 26, 27]. Prior to the experiment, the
semantic relatedness between prime and target words was rated on a
7-point scale (1 = unrelated, 7 = strongly related) by 18 independently
recruited subjects. In order to diminish the overlap between catego-
Semantic Priming and Paranormal Belief
Psychopathology 2001;34:75–80
77
ries, 18 word pairs were replaced, and a rerating by another 21 sub-
jects was done. Eventually, the prime-target pairs of the three catego-
ries were higly significantly different according to their semantic
relatedness (ANOVA F = 581.8, d.f. = 2, 78; p ! 0.001), with mean
values of 6.4 (B 0.4), 3.4 (B 0.9) and 1.7 (B 0.4) for directly related,
indirectly related and unrelated word pairs, respectively.
Words of the different categories did not differ with respect to
word length and frequency of occurrence in German texts [36]. They
were also comparable with respect to emotionality and imaginability
as rated on a 7-point scale by another 24 students who did not partic-
ipate in the final experiment.
Stimulus Presentation
There were 8 stimulus blocks (separated by 30-second breaks),
each consisting of 60 trials (prime-target pairs) belonging to 4 catego-
ries: 10 directly related, 10 indirectly related, 10 unrelated pairs and
30 word-nonword pairs. While all prime words were presented in the
center of the visual field, half of the target words within each category
were presented on the LVF/RH, the other half to the RVF/LH. Stim-
uli were presented white on a gray background. Target eccentricity
was between 2
°
and 4.8
°
of visual angle.
Each trial consisted of three displays following each other without
time gaps: for 1,000 ms, a centered fixation cross, for the next 200 ms
a centered prime and for the last 150 ms the centered fixation again,
simultaneously with a lateralized target. Thus, prime-target stimulus
onset asynchrony (SOA) was 200 ms, ensuring automatic rather than
controlled processing [37]. The screen remained blank until the sub-
ject’s manual response initiated the next trial. Manual responses con-
sisted in pressing two lateral keys simultaneously with both thumbs
(on detecting a real word) or in pressing a third key with the right
thumb (on detecting a nonword). Speed and accuracy were equally
emphasized in the instructions.
After 20 practice trials, each subject received the same pseudo-
random sequence of trials, with the constraints that (1) no more than
three trials of the same category were presented consecutively, and
(2) no more than three targets in the same visual field were presented
consecutively.
A PC with ERTS software (BeriSoft Cooperation, Frankfurt, Ger-
many) was used for stimulus presentation and reaction time (RT)
recording. A chin and head rest kept the distance between subject’s
eyes and the PC screen constant (100 cm).
Questionnaire
Before the priming task, subjects were administered the Magical
Ideation scale [19], a commonly used schizotypy inventory that con-
sists of 30 true/false items on hallucination-like experiences and delu-
sion-like beliefs.
Results
Reported RTs are in milliseconds. All p values are two-
tailed.
Magical Ideation
The two subject groups differed in their Magical Idea-
tion scores (believers 13.75 B 4.14; disbelievers 4.25 B
2.93; t = 6.56, d.f. = 1, 22; p ! 0.0005).
Fig. 1.
Mean reaction times for believers (open circles, n = 12) and
disbelievers (closed squares, n = 12) as a function of side of target
presentation and of the semantic relation between prime and target
(direct, indirect, unrelated).
Priming Task
A three-way ANOVA with ‘Group’ (believers, disbe-
lievers) as between-subject factor, and ‘Visual Field’ (VF;
LVF, RVF) and ‘Category’ (directly related, indirectly
related, unrelated prime-target relation) as repeated mea-
sures was performed on individual mean RTs of correct
lexical decisions, after removal of outliers (!400 ms,
12,400 ms; 2.3% of the data). Alternative strategies for
outlier removal (calculated as suggested by peer review)
did not affect the statistical results (first step: removal of
RTs exceeding 3,000 ms as not reliably reflecting pro-
cesses of semantic priming; second step: removal of RTs
exceeding twice the mean RT [11, 12] for every combina-
tion of VF and Category). The same three-way ANOVA
on accuracy scores did not reveal any effects or interac-
tions with Group; therefore, further analyses concentrate
on RT data. Three significant effects were observed: a
main effect for VF (LVF 972 1 RVF 896; F = 17.02, d.f. =
1, 22; p ! 0.0004), a main effect for Category (direct 844 !
indirect 948 ! unrelated 1,010; F = 21.73; d.f. = 2, 44;
Greenhouse-Geisser corrected p ! 0.0001; post hoc com-
parisons, Neuman-Keuls, all p ! 0.02) and a three-way
interaction Group ! VF ! Category (F = 5.11, d.f. =
2, 44; p ! 0.01; fig. 1).
To further explore the significant triple interaction,
separate two-way (Group ! VF) ANOVAs were per-
formed for directly related, indirectly related and unre-
lated word pairs. Apart from the main effect for VF (p !
0.05 for all categories), these analyses revealed a signifi-
cant Group ! VF interaction only for indirectly related
targets (F = 6.32, d.f. = 1, 22; p ! 0.02). Believers had
significantly shorter RTs than disbelievers when the indi-
78
Psychopathology 2001;34:75–80
Pizzagalli/Lehmann/Brugger
Fig. 2.
Mean direct and indirect semantic priming effects for believ-
ers (open bars; n = 12) and disbelievers (closed bars; n = 12) as a
function of side of target presentation. Significance of priming effects
according to post hoc tests of the three-way ANOVA of the mean
RTs. Arrows illustrate significant differences between groups (heavy
line), within groups (thin lines) and between visual fields (dashed
line) according to the three-way ANOVA of the priming effects. * p !
0.05; ** p ! 0.001.
rectly related target was in the LVF (p ! 0.0003), but not
when it was in the RVF (p 1 0.3).
Post hoc tests assessed direct and indirect semantic
priming effects comparing RTs for directly related, indi-
rectly related and unrelated targets. For disbelievers, the
following results emerged: (1) within each VF, RTs to
directly related targets (LVF 900 B 90; RVF 846 B 109)
differed from both RTs to indirectly related (LVF 1,081
B 209; p ! 0.001; RVF 924 B 160; p ! 0.05) and to unre-
lated targets (LVF 1,058 B RVF 1,004 B 177), i.e. direct
semantic priming was significant in both VFs (fig. 2);
(2) RTs to indirectly related targets differed from those to
unrelated targts only in the RVF, i.e. indirect semantic
priming was significant only in the RVF (fig. 2). For
believers, it was found that: (1) within each VF, both RTs
to directly (LVF 864 B 146; RVF 766 B 114) and to indi-
rectly related (LVF 912 B 177; RVF 875 B 199) targets
differed from those to unrelated targets (LVF 1,014 B
256; RVF 961 B 271), i.e. both direct and indirect seman-
tic priming were significant in both VFs (fig. 2); (2) RTs to
directly related targets differed from those to indirectly
related targets only in the RVF (p ! 0.005).
In order to closely compare our results with those of
prior studies [11–13], direct and indirect semantic prim-
ing effects (i.e. RT differences) were subjected to a three-
way ANOVA with Group, VF and ‘Type of priming’ [di-
rect semantic priming = RT (unrelated) RT (direct);
indirect semantic priming = RT (unrelated) RT (indi-
rect)] as factors. This analysis revealed a significant main
effect for Type of priming (direct semantic priming 166 1
indirect semantic priming 62; F = 21.40, d.f. = 1, 22; p !
0.001) and a significant Group ! VF ! Type of priming
interaction (F = 10.74, d.f. = 1, 22; p ! 0.005). Post hoc
tests (fig. 2) showed that (1) for disbelievers, direct seman-
tic priming (LVF 158 B 214; RVF 158 B 112) differed
from indirect semantic priming (LVF 23 B 92; RVF 80
B 80) within each VF; (2) for believers, direct semantic
priming (LVF 151 B 184; RVF 196 B 180) differed from
indirect semantic priming (LVF 103 B 153; RVF 87 B
100) only in the RVF; (3) for disbelievers, VF differences
were significant only for indirect semantic priming, and
(4) the only group effect was in the LVF and exclusively
for indirect semantic priming.
Discussion
Semantic priming, a paradigm developed for the study
of automatic spreading activation within semantic net-
works [3], is increasingly used within a neuropsychiatric
framework (see Spitzer [4] for review). It is argued that the
‘oblique’, ‘distant’ or ‘indirect’ associations observed in
the language of patients with thought disorder [1] are a
direct consequence of a disinhibited spreading activation
(i.e. a faster and farther spread of semantic activation)
and may manifest themselves as increased semantic prim-
ing effects [2, 10]. More recently, the technique of ‘indi-
rect semantic priming’ (which uses prime-target pairs
exclusively related through a semantically mediating con-
cept) was recognized as more sensitive for the differentia-
tion between thought-disordered and non-thought-disor-
dered schizophrenic patients; while indirect semantic
priming was enhanced in patients with thought disorder,
direct semantic priming was not [11–13, 16].
The aim of the present study was to investigate, in
healthy volunteers, direct and indirect semantic priming
as a function of one particular aspect of ‘schizotypal’
thought, i.e. a belief in ‘paranormal’ phenomena. Such
belief is assumed to be a consequence of ‘seeing’ connec-
tions between remotely (or even randomly) associated
concepts or events, which results in an attribution of
‘meaningfulness’ to coincidences [20, 38–40]. A relative
preference for distant over close associations may reflect
an overreliance on semantic processing characteristics of
the RH (i.e. a coarse as opposed to focused analysis [25–
Semantic Priming and Paranormal Belief
Psychopathology 2001;34:75–80
79
28]). Since believers in paranormal phenomena repeated-
ly showed an enhanced RH participation in a variety of
lateralized verbal tasks [30, 41, 42], we predicted that
believers would show enhanced indirect semantic prim-
ing specifically when targets were presented to the LVF.
This hypothesis was confirmed; in our sample of presel-
ected high and low scorers (all women) on a brief paranor-
mal belief scale [31], we found that the two subject groups
differed only in their RTs to indirectly related prime-tar-
get pairs and exclusively after LVF/RH presentation.
Believers showed stronger indirect (but not direct) seman-
tic priming effects than disbelievers after LVF (but not
RVF) stimulations, indicating a faster appreciation of
specifically distant semantic relations which was, how-
ever, confined to the RH. In fact, after LVF/RH stimula-
tion, believers treated indirectly related prime-target pairs
like directly related pairs, while disbelievers treated them
like unrelated pairs. The RT pattern displayed by the dis-
believers is thus similar to that of the normal control sub-
jects in previous studies of indirect semantic priming in
patients with schizophrenia [11–13]. The believers’ RT
pattern to directly and indirectly related prime-target
pairs, on the other hand, is comparable to the one found
in groups of thought-disordered patients [11–13]. One
discrepancy to a previously published study concerns the
interaction between type of priming and the visula field of
presentation. Weisbrod et al. [13], in a lateralized direct
and indirect semantic priming experiment with thought-
disordered and non-thought-disordered schizophrenic pa-
tients found indirect semantic priming also in the LH of
thought-disordered subjects. Procedural differences be-
tween these authors’ and the present experiment may
account for this discrepancy. First of all, all subjects in
Weisbrod et al. [13] were men, while we tested only
female subjects. As a rule, the regular LH superiority for
the processing of linguistic material is more pronounced
for men than women [33]. Also, all patients in the pre-
vious study were on neuroleptic medication, and neuro-
leptics are known to stabilize hemispheric asymmetries,
in particular by a normalization of LH functioning [43].
Finally, with respect to the parameters of stimulus presen-
tation, we note that differences between the two studies in
SOAs are unlikely to account for the LH contribution
observed in the Weisbrod et al. study; both these authors
(SOA = 250 ms) and ourselves (SOA = 200 ms) used val-
ues well below those considered to tap controlled rather
than automatic semantic processes [37]. On the other
hand, we presented the lateralized target words for
150 ms, while Weisbrod et al. used an exposure time of
200 ms. RH participation in lexical decision processes
generally increases as exposure time decreases [44, 45].
Nevertheless, while the minor discrepancy between the
two studies with respect to LH participation may thus be
explained by procedural differences, we would like to
emphasize that, with respect to the main point of interest,
i.e. RH participation in the processing of specifically indi-
rect semantic associations, the findings between the two
studies were identical ‘in that the most pronounced indi-
rect priming effect was found in the right hemisphere of
thought-disordered subjects’ [13, p. 146] (‘thought-disor-
dered subjects’ to be replaced by ‘paranormal believers’ in
the case of the present study).
In view of these findings, we propose that both para-
normal and delusional forms of ‘seeing’ connections be-
tween remotely associated concepts or ideas rely on an
increased spread of activation within semantic networks.
However, the same mechanisms may also be responsible
for a creative style of thinking, i.e. the ability of ‘forming
associative elements into new combinations’ [46, p. 221].
(For the electrophysiology of loosened connectivity in
schizophrenia see [4–7].) A disinhibition of semantic net-
work functioning may indeed by the physiological basis of
the commonalities between ‘genius and madness’, noted
for over a century [47]. Crow [29] recently pointed to the
longstanding puzzle how ‘genes predisposing to schizo-
phrenia survive in all populations without a balancing
advantage being apparent’ [29, p. 339]. The view of a con-
tinuum of associative loosening seems to provide a solu-
tion to this puzzle: while a pronounced disinhibition may
lead to maladaptive, disordered thought, more moderate
forms can lead to creative insights and thus constitute an
obvious evolutionary advantage.
While our findings provide insight into the formation
and maintenance of paranormal belief, their implications
for neuropsychiatry may be much broader. They illustrate
the usefulness of testing healthy subjects for the under-
standing of the neuropsychobiological mechanisms po-
tentially underlying psychiatric symptoms. This approach
has considerable advantages over testing patients, a pro-
cedure often meeting serious problems with respect to
patients’ compliance, interpretation of medication effects
and, in priming studies, of RT baseline differences be-
tween patient and control groups [9].
Acknowledgments
The authors thank L. Gianotti, MA, and C. Mohr, MA, for tech-
nical assistance. This study was supported by the Institut für Grenz-
gebiete der Psychologie und Psychohygiene, Freiburg i. Br., Germa-
ny (Grants #67 13 10 and #67 08 06).
80
Psychopathology 2001;34:75–80
Pizzagalli/Lehmann/Brugger
References
1 Bleuler E: Dementia Precox or the Group of
Schizophrenias (translated by J. Zinkin). New
York, International Universities Press, 1911/
1950.
2 Maher BA: Language and schizophrenia; in
Nasrallah HA (ed): Handbook of Schizophre-
nia: Neuropsychology, Psychophysiology and
Information Processing. Amsterdam, Elsevier,
1991, vol 5, pp 437–464.
3 Collins A, Loftus E: A spreading activation the-
ory of semantic processing. Psychol Rev 1975;
82:407–428.
4 Spitzer M: A cognitive neuroscience view of
schizophrenic thought disorder. Schizophr Bull
1997;23:29–50.
5 Koukkou M, Lehmann D, Wackermann J,
Dvorak I, Henggeler B: Dimensional com-
plexity of EEG brain mechanisms in untreated
schizophrenia. Biol Psychiatry 1993;33:397–
407.
6 Friston KJ: Theoretical neurobiology and
schizophrenia. Br Med Bull 1996;52:644–655.
7 Saito N, Kuginuki T, Yagyu T, Kinoshita T,
Koenig T, Pascual-Marqui RD, Kochi K,
Wackermann J, Lehmann D: Global, regional
and local measures of complexity of multichan-
nel EEG in acute, neuroleptic-naive, first-break
schizophrenics. Biol Psychiatry 1998;43:794–
802.
8 Henik A, Nissimov E, Priel B, Umansky R:
Effects of cognitive load on semantic priming
in patients with schizophrenia. J Abnorm Psy-
chol 1995;104:576–584.
9 Kwapil TR, Hegley D, Chapman LJ, Chapman
JP: Facilitation of word recognition by seman-
tic priming in schizophrenia. J Abnorm Psy-
chol 1990;99:215–221.
10 Manschreck TC, Maher BA, Milavetz JJ, Ames
D, Weisstein CC, Schneyer ML: Semantic
priming in thought disordered schizophrenic
patients. Schizophr Res 1988;1:61–66.
11 Spitzer M, Braun U, Hermle L, Maier S: Asso-
ciative semantic network dysfunction in
thought-disordered schizophrenic patients: Di-
rect evidence from indirect semantic priming.
Biol Psychiatry 1993;34:864–877.
12 Spitzer M, Braun U, Maier S, Hermle L, Maher
BA: Indirect semantic priming in schizophren-
ic patients. Schizophr Res 1993;11:71–80.
13 Weisbrod M, Maier S, Harig S, Himmelsbach
U, Spitzer M: Lateralised semantic and indi-
rect priming effects in people with schizophre-
nia. Br J Psychiatry 1998;172:142–146.
14 Henik A, Priel B, Umansky R: Attention and
automaticity in semantic processing of schizo-
phrenic patients. Neuropsychiatry Neuropsy-
chol Behav Neurol 1992;5:161–169.
15 Balota DA, Lorch RF: Depth of automatic
spreading activation: Mediated priming effects
in pronounciation but not in lexical decisions. J
Exp Psychol Learn Mem Cogn 1986;12:336–
345.
16 Spitzer M, Weisbrod M, Winkler S, Maier S:
Ereigniskorrelierte Potentiale bei semantischen
Sprachverarbeitungsprozessen schizophrener
Patienten. Nervenarzt 1997;68:212–225.
17 Claridge G, Broks P: Schizotypy and hemi-
sphere function. I. Theoretical considerations
and the measurement of schizotypy. Person
Individ Differ 1984;5:633–648.
18 Thalbourne MA: Belief in the paranormal and
its relationship to schizophrenia-relevant mea-
sures: A confirmatory study. Br J Clin Psychol
1994;33:78–80.
19 Eckblad M, Chapman LJ: Magical ideation as
an indicator of schizotypy. J Consult Clin Psy-
chol 1983;51:215–225.
20 Brugger P, Regard M, Landis T, Graves RE:
The roots of meaningful coincidence. Lancet
1995;345:1306–1307.
21 Duchêne A, Graves RE, Brugger P: Schizotypal
thinking and associative processing: A response
commonality analysis of verbal fluency. J Psy-
chiatry Neurosci 1998;23:56–60.
22 Merten T: Word association responses and psy-
choticism. Person Individ Differ 1993;14:837–
839.
23 Miller EN, Chapman LJ: Continued word asso-
ciation in hypothetically psychosis-prone col-
lege students. J Abnorm Psychol 1983;92:468–
487.
24 Reilly F, Harrow M, Tucker G, Quinlan D, Sie-
gel A: Looseness of associations in acute schizo-
phrenia. Br J Psychiatry 1975;127:240–246.
25 Anaki D, Faust M, Kravetz S: Cerebral hemi-
spheric asymmetries in processing lexical meta-
phors. Neuropsychologia 1998;36:353–362.
26 Beeman M, Friedman RB, Grafman, Perez E,
Diamond S, Beadle Lindsay M: Summation
priming and coarse semantic coding in the
right hemisphere. J Cogn Neurosci 1994;6:26–
45.
27 Chiarello C, Burgess C, Richards L, Pollock A:
Semantic and associative priming in the cere-
bral hemispheres: Some words do, some words
don’t.... sometimes, some places. Brain Lang
1990;38:75–104.
28 Faust M, Chiarello C: Sentence context and
lexical ambiguity resolution by the two hemi-
spheres. Neuropsychologia 1998;36:827–835.
29 Crow TJ: Schizophrenia as failure of hemi-
spheric dominance for language. Trends Neu-
rosci 1997;20:339–343.
30 Leonhard D, Brugger P: Creative, paranormal,
and delusional thought: A consequence of right
hemisphere semantic activation? Neuropsy-
chiatry Neuropsychol Behav Neurol 1998;11:
177–183.
31 Mischo J, Boller E, Braun G: Fragebogenunter-
suchung zur Erfassung von okkulten Glaubens-
haltungen und Merkmalen schizotypischer
Verarbeitung. Freiburg, Institut für Grenzge-
biete der Psychologie und Psychohygiene,
1993.
32 Schienle A, Vaitl D, Stark R: Covariation bias
and paranormal belief. Psychol Rep 1996;78:
291–305.
33 Beaton A: Left Side, Right Side: A Review of
Laterality Research. London, Batsford, 1985.
34 Chapman LJ, Chapman JP: The measurement
of handedness. Brain Cogn 1987;6:175–183.
35 Chiarello C, McMahon MA, Schaefer K: Visual
cerebral lateralization over phases of the men-
strual cycle: A preliminary investigation. Brain
Cogn 1989;11:18–36.
36 Ruoff A: Häufigkeitswörterbuch gesprochener
Sprache. Tübingen, Niemeyer, 1990.
37 Collins M: Differences in semantic category
priming in the left and right cerebral hemi-
spheres under automatic and controlled pro-
cessing conditions. Neuropsychologia 1999;37:
1071–1085.
38 Blackmore S, Moore R: Seeing things: Visual
recognition and belief in the paranormal. Eur J
Parapyschol 1994;10:91–97.
39 Brugger P, Graves RE: Testing vs. believing
hypothesis: Magical ideation in the judgements
of contingencies. Cogn Neuropsychiatry 1997;
2:251–272.
40 Brugger P, Regard M, Landis T, Cook N, Krebs
D, Niederberger J: ‘Meaningful’ patterns in
visual noise: Effects of lateral stimulation and
the observer’s belief in ESP. Psychopathology
1993;26:261–265.
41 Broks P: Schizotypy and hemisphere function.
II. Performance asymmetry on verbal divided
visual-field task. Person Individ Differ 1984;5:
649–656.
42 Poreh AM, Whitman DR, Ross TP: Creative
thinking and hemispheric asymmetry in schi-
zotypal college students. Curr Psychol 1993/94:
12:344–352.
43 Tomer R, Flor-Henry P: Neuroleptics reverse
attention asymmetries in schizophrenic pa-
tients. Biol Psychiatry 1989;25:852–860.
44 Pring PT: The effects of stimulus-size and ex-
posure duration on visual field asymmetry.
Cortex 1981;17:227–239.
45 Regard M, Landis T: Dissociated hemispheric
superiorities for reading stenography vs. print.
Neuropsychologia 1985;23:431–435.
46 Mednick SA: The associative basis of the cre-
ative process. Psychol Rev 1962;69:220–232.
47 Galton F: Hereditary Genius. London, Mac-
millan, 1892.
... As with the production of more original responses in fluency tasks, increased false memory responses could be argued to result from enhanced spreading of activation from stimulus words to unpresented but semantically related critical words, a transmission of activation that is sufficient to trigger false positives in response to recall or recognition tests. Crucially, in accordance with previous observations with schizophrenia patients (see Pomarol-Clotet et al., 2008), some authors argue that this mechanism could also underlie the presence of atypical speech patterns or ideas of reference associating unrelated events in schizotypal individuals (Mohr et al., 2001;Pizzagalli, Lehmann & Brugger, 2001). Nevertheless, other studies have failed to obtain significant associations between the originality of fluency responses (Hori et al., 2008;Rodríguez-Ferreiro & Aguilera, 2019) or semantic-based false memory rates (Corlett et al., 2009;Kanemoto et al., 2013;Rodríguez-Ferreiro, Aguilera & Davies, 2020) and differences on schizotypal traits, so the reliability of these observations is unclear. ...
... Our study focused on examining the possible association between variability in semantic processing and differences in thought disorder as measured by cognitive disorganization scales of schizotypy questionnaires in sub-clinical volunteers. However, some authors have suggested that disturbances in semantic processing could also be associated with individual differences in positive traits such as dissociative experiences (Dehon, Bastin & Larøi, 2008;Winogard, Peluso & Glover, 1998) hallucinations (Kanemoto et al., 2013;Sugimori, Asai & Tanno, 2011) or paranormal beliefs (Meyersburg et al., 2009;Pizzagalli, Lehmann & Brugger, 2001). Our study is also informative in relation to this hypothesis because we employed the questionnaire measures (SPQ-B and sO-LIFE) to estimate individual differences not only in disorganized traits, but also in positive and negative traits. ...
... Ambilaterality has been associated with schizotypal traits such as magical thinking (Barnett & Corballis, 2002), and functional hemispheric asymmetry, which is known to be associated with handedness (Bourne, 2006), has been suggested to share a neural basis with schizotypy (Schmitz et al., 2019). Along these lines, previous studies have reported stronger priming effects in paranormal believers, compared to disbelievers, only after left visual field presentation of the words (Mohr, Landis & Brugger, 2006;Pizzagalli, Lehmann & Brugger, 2001). Taking these observations into account, recruitment of homogeneous right-handed samples or samples including comparable groups of right-handed and left-handed participants and left-lateralized presentation of priming stimuli might be more adequate to capture the relation between schizotypal traits and semantic processing and should be considered in further studies. ...
Article
Full-text available
The term schizotypy refers to a group of stable personality traits with attributes similar to symptoms of schizophrenia, usually classified in terms of positive, negative or cognitive disorganization symptoms. The observation of increased spreading of semantic activation in individuals with schizotypal traits has led to the hypothesis that thought disorder, one of the characteristics of cognitive disorganization, stems from semantic disturbances. Nevertheless, it is still not clear under which specific circumstances (i.e., automatic or controlled processing, direct or indirect semantic relation) schizotypy affects semantic priming or whether it does affect it at all. We conducted two semantic priming studies with volunteers varying in schizotypy, one with directly related prime-target pairs and another with indirectly related pairs. Our participants completed a lexical decision task with related and unrelated pairs presented at short (250 ms) and long (750 ms) stimulus onset asynchronies (SOAs). Then, they responded to the brief versions of the Schizotypal Personality Questionnaire and the Oxford-Liverpool Inventory of Feelings and Experiences, both of which include measures of cognitive disorganization. Bayesian mixed-effects models indicated expected effects of SOA and semantic relatedness, as well as an interaction between relatedness and directness (greater priming effects for directly related pairs). Even though our analyses demonstrated good sensitivity, we observed no influence of cognitive disorganization over semantic priming. Our study provides no compelling evidence that schizotypal symptoms, specifically those associated with the cognitive disorganization dimension, are rooted in an increased spreading of semantic activation in priming tasks.
... This is characterized by a marked eccentricity in terms of appearance, behavior, and thinking. Research has consistently reported an association between this personality type and belief in the paranormal (Pizzagalli, Lehmann, and Brugger, 2001;Shiah et al., 2014;Thalbourne, 1995;Thalbourne & French, 1995;Williams, 1991;Wolfradt, 1997). However, there are authors that question this association (Denovan, Dagnall, Drinkwater, & Parker, 2018;Parra, 2010). ...
... Schulter and Papousek (2008) also report an "atypical" functional lateralization in stronger believers. Along the same line, Pizzagalli, Lehmann, and Brugger (2001) explored the electrophysiological profiles of prescreened strong believers and disbelievers during resting baseline and reported that believers showed more right-located sources of the β2 band (18.5-21 Hz, excitatory activity), reduced interhemispheric differences in omega complexity values, higher scores on the Magical Ideation Scale, more general negative affect, and more hypnagogic-like reveries after a 4-min eyes-closed resting period. ...
Article
A large number of theories about the development and maintenance of paranormal beliefs have been raised in the literature. There is, however, a lack of studies designed to integrate the different perspectives. We reviewed the literature and explored a series of factors in a sample of 180 individuals. Seven variables showed significant correlation indices at α = .01. A regression analysis revealed subjective paranormal experience as the variable that contributed the most to the explanation of paranormal belief, z = .43, 95% confidence interval (CI) [.24, .56]. Need for achievement (z = .31, 95% CI [.11, to .46]), conditional reasoning (z = .10, 95% CI [.09, .28]), and schizotypy (z = .29, 95% CI [.09, .45]) also contributed significantly in the equation. The associations found between the subscales of the Needs Questionnaire and belief in the paranormal support the hipothesis that paranormal belief may serve basic psychological needs. Similarly, the association found in the case of schizotypy suggests that paranormal belief might be held within the context of psychopathology. There was no evidence, however, supporting the hypothesis of a reasoning deficit in believers. It was concluded that, once paranormal beliefs develop, there is an interaction between belief and experience that strongly contributes towards its maintenance.
... Finally, four papers (n = 368) explored other aspects of cognitive function not covered by the categories already described. Pizzagalli et al. [166] tested the association between indirect semantic priming and paranormal beliefs using 240 prime-target word pairs, with target words either directly related, indirectly related, or unrelated to the prime word. Compared to sceptics, believers had shorter reaction times for indirectly related target words were presented in the left visual field, suggesting a faster appreciation of distant semantic associations which the authors view as evidence of disordered thought. ...
Article
Full-text available
Article Authors Metrics Comments Media Coverage Peer Review Abstract Introduction Method Results General discussion Conclusions Supporting information References Reader Comments Figures Accessible Data IconAccessible Data See the data Link Icon This article includes the Accessible Data icon, an experimental feature to encourage data sharing and reuse. Find out how research articles qualify for this feature. Abstract Background Research into paranormal beliefs and cognitive functioning has expanded considerably since the last review almost 30 years ago, prompting the need for a comprehensive review. The current systematic review aims to identify the reported associations between paranormal beliefs and cognitive functioning, and to assess study quality. Method We searched four databases (Scopus, ScienceDirect, SpringerLink, and OpenGrey) from inception until May 2021. Inclusion criteria comprised papers published in English that contained original data assessing paranormal beliefs and cognitive function in healthy adult samples. Study quality and risk of bias was assessed using the Appraisal tool for Cross-Sectional Studies (AXIS) and results were synthesised through narrative review. The review adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and was preregistered as part of a larger registration on the Open Science Framework (https://osf.io/uzm5v). Results From 475 identified studies, 71 (n = 20,993) met our inclusion criteria. Studies were subsequently divided into the following six categories: perceptual and cognitive biases (k = 19, n = 3,397), reasoning (k = 17, n = 9,661), intelligence, critical thinking, and academic ability (k = 12, n = 2,657), thinking style (k = 13, n = 4,100), executive function and memory (k = 6, n = 810), and other cognitive functions (k = 4, n = 368). Study quality was rated as good-to-strong for 75% of studies and appears to be improving across time. Nonetheless, we identified areas of methodological weakness including: the lack of preregistration, discussion of limitations, a-priori justification of sample size, assessment of nonrespondents, and the failure to adjust for multiple testing. Over 60% of studies have recruited undergraduates and 30% exclusively psychology undergraduates, which raises doubt about external validity. Our narrative synthesis indicates high heterogeneity of study findings. The most consistent associations emerge for paranormal beliefs with increased intuitive thinking and confirmatory bias, and reduced conditional reasoning ability and perception of randomness. Conclusions Although study quality is good, areas of methodological weakness exist. In addressing these methodological issues, we propose that authors engage with preregistration of data collection and analysis procedures. At a conceptual level, we argue poorer cognitive performance across seemingly disparate cognitive domains might reflect the influence of an over-arching executive dysfunction.
... Assumption deficiency, which claims that such a belief comes from a mental defect, from intelligence reduced to the lack of critical thinking reaching full psychosis. The deficiency hypothesis is supported the fact that this belief in the paranormal is an aspect of the schizotypal personality (Pizzagalli, Lehman and Brugger, 2001). ...
Article
Full-text available
... En la misma línea, Schulter y Papousek (2008) reportan una lateralización funcional atípica en los creyentes más convencidos. Pizzagalli, Lehmann, y Brugger (2001) analizaron los perfiles electrofisiológicos de individuos creyentes y no creyentes, y observaron que los creyentes mostraron un patrón excitatorio más desplazado hacia la derecha de la banda β2 (18.5 -21 Hz), una reducción de las diferencias interhemisféricas en los valores de complejidad Omega, puntuaciones más altas en la Escala de Ideación Mágica, un afecto negativo más general y más imaginería hipnagógica después de un período de relajación. Del mismo modo, y consistente con la literatura previa, los creyentes en lo paranormal mostraron una activación del hemisferio derecho relativamente más alta y una asimetría hemisférica reducida. ...
Article
Full-text available
La literatura muestra una amplia gama de teorías y factores que contribuyen a la formación y mantenimiento de creencias paranormales. En este estudio se analiza una serie de variables relacionadas con las principales explicaciones propuestas en una muestra de 184 sujetos. La esquizotipia (rxy = .23, p < .001), las experiencias inusuales (rxy = .37, p < .001), la anhedonia introvertida (rxy = .28, p < .001), la habilidad de razonamiento condicional en tareas con contenido paranormal (rxy = .23, p = .001), la necesidad de afiliación (rxy = .21, p = .002) y la vivencia de experiencias extraordinarias subjetivas (rxy = .35, p < .001) correlacionaron significativamente con la creencia en lo paranormal. Los resultados son consistentes con la teoría de la compensación de necesidades de Russell y Jones (1980) e indican que la ideología puede aparecer asociada a signos premórbidos y/o ser consecuencia de psicopatología. Sin embargo, sugieren que la creencia en lo paranormal puede no ser consecuencia de una deficiencia de razonamiento probabilístico y/o condicional. Se sugiere un modelo integrador basado en el feedback entre creencia y experiencia.
... While some studies on paranormal beliefs focus on relating these factors of unconventional beliefs with various psychological traits linked to cognitive or affective dysfunction (e.g. Pizzagalli, Lehmann, and Brugger 2001;Hergovich, Schott, and Arendasy 2008), other studies have also shown that these beliefs systems are not associated with psychological dysfunctions (Roe 1999). Aside from psychological functions, another important predictor of religiosity is 'sociodemographic characteristics' (Cornwall 1998). ...
Article
This study examines sociodemographic and wellbeing factors associated with forms of religiosity involving conventional religious belief (CRB) and daily spiritual experience (DSE), and unconventional paranormal beliefs in lifeforms (UPBL) and paranormal beliefs excluding extraordinary lifeforms (UPBEEL). Self-reported data collected from Australian Facebook users (N = 760; Female: 57%) suggest that CRB was significantly higher in Christian participants and lower in those who identify as non-religious and spiritual. However, levels of unconventional religiosity involving UPBL and UPBEEL were significantly higher among Pagans and those who identify as spiritual but not religious, but lower among non-religious participants. Compared to Christian participants, being spiritual and pagan were negatively associated with the level of security. After controlling for relevant sociodemographic characteristics, conventional forms of religiosity involving DSE were positively related to life satisfaction, life security, and trust level. UPBL was also positively associated with wellbeing outcomes but UPBEEL was inversely related to all wellbeing outcomes. Further analysis reveals that religious status moderates the links between conventional and unconventional forms of religiosity, such that paranormal beliefs tended to be higher when CRB and DSE each had a unique interaction with religious status. These results show that forms of religiosity are related to wellbeing differently and suggest the influence of cognitive biases related to religious/spiritual teachings and experiences in enacting the quest for deeper spiritual, paranormal experiences. Study limitations are discussed.
... . . . it is the associating of paranormal belief formation and maintenance with schizotypal ideation (Brugger et al. 1993, Brugger & Graves 1997, Hergovich, Schott, & Arendasy 2008, Irwin & Green 1998, Pizzagalli et al. 2000, Pizzagalli, Lehmann, & Brugger 2001, Thalbourne, Dunbar, & Delin 1995, Windholz & Diamant 1974, delusion, psychosis, and schizophrenia (e.g., Cella, Vellante, & Preti 2012, Houran & Lange 2004, Thalbourne 1994) that most successfully creates an impression that paranormal believers are psychologically dysfunctional. (Jinks 2012a:128) We do not entirely dispute the insights drawn from some correlates and functions of PB (see Irwin & Watt 2007, Kumar & Pekala 2001, Lange & Houran 1997, and it is clear that many psi-researchers place great emphasis and importance on PB scales for scientifi c reasonsfor example, due to the often-supported psi and sheep-goat hypotheses, 1 sheep are usually regarded as probable high-scorers on tests of psychic ability whereas goats are not (see Lawrence 1993, Palmer 1971, 1977. ...
Article
Full-text available
This study examined the degree to which paranormal believers, who profess 'strong' belief in the popular expression of a topic known as the primary item (e.g., Psychics possess a mysterious ability to know things about a person's past and future), disagree with related items and/or the putative 'cause' of the topic, known as secondary items (e.g., Some people have a mysterious ability to accurately predict such things as natural disasters, election results, political assassinations, etc.). It was theorized that scoring diff erences between primary and secondary items might indicate certain kinds of paranormal believer, which might then allow us to conduct deeper analyses of paranormal belief (PB) and its putative relationships with deficits and dysfunctions. A complete set of items drawn from ten established PB scales was administered to a sample of 343 respondents. Using Factor Analysis, we developed the Paranormal Belief Informedness Scale (PBIS), consisting of 10 primary items, and 10 secondary items, scores of which were used to identify three major PB types: 'primary believers' (who believe in all 10 primary items, and thus exhibit 'strong' PB), 'primary non-believers' (who believe in none of the 10 primary items), and 'mixed believers' (who believe in only some primary items). We found significant response-rate diff erences between primary and secondary items across believer types, and across psi categories (i.e. extra-sensory perception, psychokinesis, and life after death). For the full sample, it was shown that there is a significant relationship between PB and reality testing deficits as measured on the reality testing subscale of the Inventory of Personality Organisation (IPO-RT) (Lenzenweger et al. 2001). However, this relationship tended not to be significant across believer types. Also, there was no evidence in the full sample, or in any believer type, that PB was correlated with depression as measured on the Beck Depression Inventory (BDI-II). We suggest that paranormal believers have diff erences that may be reflected in their responses to predictor variables, and/or in how informed their paranormal belief is.
... In recent years, our knowledge of the cognitive and neural underpinnings of schizotypy has grown immensely. There have been studies reporting positive correlations between this personality trait and left temporal lobe dysfunction (Mohr, et al., 2001), a loosening or disinhibition of semantic network functioning (Pizzagalli, Lehmann, Brugger, 2001), and an overactivation of the right hemisphere (Pizzagalli, et al., 2000). These correlations -which are not an indication of pathology but of a distinct cognitive and neural functioning -are evidence of what may underlie experiences of unusual ideas and perceptions, like those described in spirituality scales. ...
... Theoretically, this hypothesis relies on a conception of semantic memory as a network of interconnected nodes in which, when a given node is activated, semantic activation spreads to associated nodes, with stronger associates receiving higher activation levels than weaker ones (Collins and Loftus, 1975). From this point of view, increased semantic activation spreading in schizotypal individuals, leading to over-activation of loosely associated concepts, could explain the appearance of atypical speech patterns with associative intrusions, as well as ideas of reference or magical ideation connecting unrelated events in high schizotypes (Mohr et al., 2001;Pizzagalli et al., 2001). ...
Article
Full-text available
Enhanced spreading of semantic activation has been hypothesized to underlie some of the most significant symptoms of schizotypal personality, like thought disorder, odd speech, delusion, or magical thinking. We applied the Deese/Roediger-McDermott false memory task to the study of semantic activation in a group of 123 non-clinical individuals varying in the three dimensions of schizotypal personality: positive, negative and disorganized schizotypy. In the study phase, we presented them with lists composed of words semantically associated to unpresented critical words. Then, they responded to a recognition questionnaire including previously presented words and critical unpresented lures, as well as weakly related and unrelated unpresented lures. Participants rated their confidence in recognizing each word. They also filled in a standardized schizotypal personality questionnaire. Confirming the false memory effect, recognition ratings provided in response to critical words were higher than those produced for both weakly related and unrelated items. Crucially, scores in the positive dimension increased recognition percentages and confidence ratings for weakly related and unrelated lures. This study indicates that high levels of positive schizotypy might influence the tendency to accept false memories of unrelated unpresented material.
Article
Full-text available
Apophenia, patternicity, and the experience of meaningful coincidences describe the propensity to perceive meaning in random arrangements, which is known to be linked with paranormal beliefs. Additionally, this trait of combining unrelated elements to create new meanings suggests an association with creativity. However, studies indicating a relationship between creativity and apophenia are scarce. To gain empirical evidence, the present study (n = 77) assessed the propensity to experience meaningful patterns in random arrangements by means of a questionnaire (coincidence questionnaire) and a behavioral measure. The applied figural association task allows to reliably differentiate between the perception of idiosyncratic/unique and intersubjective meaningful/non-unique patterns. Self-rated creative ideation behavior and paranormal beliefs were positively associated with the subjectively rated frequency of meaningful coincidences. Furthermore, participants high in both creative ideation behavior and paranormal beliefs perceived a higher number of non-unique meanings in the figural association task. Yet, participants high in paranormal beliefs additionally perceived a higher number of unique meanings. This divergence in findings suggests that creative ideation behavior and paranormal belief are associated with the perception of partly different meanings in random arrangements. In paranormal believers, this pattern of findings may indicate a lower threshold to detect meaning in meaninglessness, leading to more idiosyncratic/unique perceptions. Altogether, slight reductions of this threshold to detect meaningfulness may increase a persons’ creativity; however, excessive pattern recognition may facilitate paranormal beliefs.
Article
Full-text available
Conducted lexical decision and pronunciation experiments, using a total of 140 university students, to investigate whether activation automatically spreads beyond directly associated concepts within the memory network. Prime-target pairs were constructed such that there was a relation between the prime (e.g., lion) and the target (e.g., stripes) only through a mediating concept (e.g., tiger). The lexical decision results yielded facilitation of directly related priming conditions (e.g., lion–tiger and tiger–stripes); however, the mediated condition (e.g., lion–stripes) did not facilitate performance compared with either a neutral prime or an unrelated prime condition. In contrast, the pronunciation results yielded facilitation of both directly related and mediated priming conditions. Results are viewed as supporting the notion that activation spreads beyond directly related concepts in semantic memory. It is suggested that characteristics of the lexical decision task masked the appearance of a mediated priming effect. Implications of an automatic spread of activation beyond directly related concepts are discussed. The stimulus triads used are appended. (35 ref) (PsycINFO Database Record (c) 2012 APA, all rights reserved)
Article
Full-text available
Two groups of college students that scored high (N=25) and low (N=60) on a schizotypal personality index based on the Perceptual Aberration, Magical Thinking, and Schizotypal Personality Scales, were tested for hemisphericity using a dichotic listening task and completed the Torrance Test of Creative Thinking. The schizotypy scales correlated with high scores on the nonverbal portion of the creativity tests and with a left ear preference to dichotically presented verbal stimuli. The Torrance Test of Creative Thinking did not correlate, however, with hemispheric asymmetry. These results clarify the relationship between schizotypy and creating thinking abilities but fail in establishing the role of hemispheric asymmetry in the production of creative thinking ideas.
Article
Abstract There are now numerous observations of subtle right hemisphere (RH) contributions to language comprehension. It has been suggested that these contributions reflect coarse semantic coding in the RH. That is, the RH weakly activates large semantic fields-including concepts distantly related to the input word-whereas the left hemisphere (LH) strongly activates small semantic fields-limited to concepts closely related to the input (Beeman, 1993a,b). This makes the RH less effective at interpreting single words, but more sensitive to semantic overlap of multiple words. To test this theory, subjects read target words preceded by either "Summation" primes (three words each weakly related to the target) or Unrelated primes (three unrelated words), and target exposure duration was manipulated so that subjects correctly named about half the target words in each hemifield. In Experiment 1, subjects benefited more from Summation primes when naming target words presented to the left visual field-RH (Ivf-RH) than when naming target words presented to the right visual field-LH (rvf-LH), suggesting a RH advantage in coarse semantic coding. In Experiment 2, with a low proportion of related prime-target trials, subjects benefited more from "Direct" primes (one strong associate flanked by two unrelated words) than from Summation primes for rvf-LH target words, indicating that the LH activates closely related information much more strongly than distantly related information. Subjects benefited equally from both prime types for Ivf-RH target words, indicating that the RH activates closely related information only slightly more strongly, at best, than distantly related information. This suggests that the RH processes words with relatively coarser coding than the LH, a conclusion consistent with a recent suggestion that the RH coarsely codes visual input (Kosslyn, Chabris, Mar-solek, & Koenig, 1992).
Article
This paper examines the idea that an important dimension of human cognition is the amount of objective evidence required for perception of meaningful patterns. At the clinical extreme of this dimension are patients with hallucinations and delusions who experience perception with no external evidence and see connections between objectively unrelated events. Also, normal individuals exhibit considerable variation along this continuum. The theory proposed here predicts that normal subjects with low evidential criteria will be more likely to accept causal explanations, not only for everyday ''paranormal'' coincidences, but also for random contingencies in a laboratory experiment. This prediction was confirmed when 40 students completed a differential reinforcement of low rates (DRL) task designed to induce superstitious behaviour and were then questioned about their hypotheses concerning the contingencies for successful performance. Participants scoring high on the Magical Ideation scale (indicating greater belief in paranormal phenomena) tested fewer hypotheses during the task, and they ended up believing in more hypotheses regarding illusory contingencies than did their low-scoring peers. We proposed that a continuum of hypothesis-testing behaviour underlies the schizotypy continuum, with ''positive'' schizotypal traits reflecting a Type I error bias and ''negative'' traits a Type II error bias. Differential activation patterns within frontal-limbic networks are tentatively suggested as a physiological correlate of the behavioural continuum.
Article
Several authors have attributed much of the cognitive dysfunction revealed in schizophrenia to a deficient attentional mechanism. At the same time several studies have suggested that this limited resource (i.e., attention) is involved in accessing and activating concepts within our semantic network. The present study investigates automatic and attentional processes that are involved in accessing and activating concepts within the semantic network. In two experiments with schizophrenic patients and controls, it was found that both groups showed comparable priming effects under long stimulus onset asynchrony (SOA) conditions, while the effect was less reliable in the patient population under the short SOA condition. Identical priming was present regardless of SOA conditions. The present results contribute to the analysis of the specific deficits characteristic of attentional processes in schizophrenia: while the lexical access is not different from normal, the spread of activation seems to be slowed down but may be compensated when time allows for it. These effects are discussed in the context of recent findings qualifying the automaticity of the spread of activation within the semantic network. (C) Lippincott-Raven Publishers.
Article
Ereigniskorrelierte Potentiale (EKP) erlauben die zeitlich hochauflösende Darstellung mentaler Informationsverarbeitungsprozesse. Die Methode wird seit ca. 15 Jahren zur Untersuchung psycholinguistischer Sachverhalte verwendet. Semantische Inkongruenz führt ca. 400 ms nach Stimulusbeginn zu einem negativen Potential (N400). Die Vermessung dieses Potentials bei gleichzeitiger Variation der semantischen Distanz von Hinweisreiz und Zielreiz in einer Wortentscheidungsaufgabe bei 20 gesunden Probanden und 20 schizophrenen Patienten verweist auf eine gestörte Gestaltbildung im Bereich semantischer Verarbeitungsprozesse bei schizophrenen Patienten. Ergebnisse aus früheren Untersuchungen zu Bahnungseffekten bei Reaktionszeitmessungen werden elektrophysiologisch untermauert, die Hypothese einer rascheren und vermehrten Aktivierungsausbreitung in semantischen Netzwerken bei schizophrenen Patienten wird insgesamt bestätigt. Event-related potentials (ERPs) can be used for high-resolution mental chronometry. For about 15 years, this method has been applied to the study of linguistic phenomena. Semantic incongruency produces a negative component at about 400 ms after stimulus onset, the N400. We measured the N400 component in 20 schizophrenic patients and 20 normal control subjects performing a lexical decision task in which semantic distance between prime and target was varied. The results provide evidence of dysfunctional semantic information processing in schizophrenic patients, and reaction time data from previous studies can be interpreted within an electrophysiological framework. The N400 amplitude and latency data support recent spreading activation models of schizophrenic language dysfunction.