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Individuals Who Believe in the Paranormal Expose Themselves to Biased Information and Develop More Causal Illusions than Nonbelievers in the Laboratory

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In the reasoning literature, paranormal beliefs have been proposed to be linked to two related phenomena: a biased perception of causality and a biased information-sampling strategy (believers tend to test fewer hypotheses and prefer confirmatory information). In parallel, recent contingency learning studies showed that, when two unrelated events coincide frequently, individuals interpret this ambiguous pattern as evidence of a causal relationship. Moreover, the latter studies indicate that sampling more cause-present cases than cause-absent cases strengthens the illusion. If paranormal believers actually exhibit a biased exposure to the available information, they should also show this bias in the contingency learning task: they would in fact expose themselves to more cause-present cases than cause-absent trials. Thus, by combining the two traditions, we predicted that believers in the paranormal would be more vulnerable to developing causal illusions in the laboratory than nonbelievers because there is a bias in the information they experience. In this study, we found that paranormal beliefs (measured using a questionnaire) correlated with causal illusions (assessed by using contingency judgments). As expected, this correlation was mediated entirely by the believers' tendency to expose themselves to more cause-present cases. The association between paranormal beliefs, biased exposure to information, and causal illusions was only observed for ambiguous materials (i.e., the noncontingent condition). In contrast, the participants' ability to detect causal relationships which did exist (i.e., the contingent condition) was unaffected by their susceptibility to believe in paranormal phenomena.
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RESEARCH ARTICLE
Individuals Who Believe in the Paranormal
Expose Themselves to Biased Information
and Develop More Causal Illusions than
Nonbelievers in the Laboratory
Fernando Blanco
1
*, Itxaso Barberia
2,3
, Helena Matute
1
1Labpsico, Departamento de Fundamentos y Métodos de la Psicología, Universidad de Deusto, Bilbao,
Spain, 2The Event Lab, Facultat de Psicologia, Universitat de Barcelona, Barcelona, Spain, 3Departament
de Psicologia Bàsica, Facultat de Psicologia, Universitat de Barcelona, Barcelona, Spain
*fernandoblanco@deusto.es
Abstract
In the reasoning literature, paranormal beliefs have been proposed to be linked to two
related phenomena: a biased perception of causality and a biased information-sampling
strategy (believers tend to test fewer hypotheses and prefer confirmatory information). In
parallel, recent contingency learning studies showed that, when two unrelated events coin-
cide frequently, individuals interpret this ambiguous pattern as evidence of a causal relation-
ship. Moreover, the latter studies indicate that sampling more cause-present cases than
cause-absent cases strengthens the illusion. If paranormal believers actually exhibit a
biased exposure to the available information, they should also show this bias in the contin-
gency learning task: they would in fact expose themselves to more cause-present cases
than cause-absent trials. Thus, by combining the two traditions, we predicted that believers
in the paranormal would be more vulnerable to developing causal illusions in the laboratory
than nonbelievers because there is a bias in the information they experience. In this study,
we found that paranormal beliefs (measured using a questionnaire) correlated with causal
illusions (assessed by using contingency judgments). As expected, this correlation was
mediated entirely by the believers' tendency to expose themselves to more cause-present
cases. The association between paranormal beliefs, biased exposure to information, and
causal illusions was only observed for ambiguous materials (i.e., the noncontingent condi-
tion). In contrast, the participants' ability to detect causal relationships which did exist (i.e.,
the contingent condition) was unaffected by their susceptibility to believe in paranormal
phenomena.
Introduction
Despite the availability of scientific knowledge and efforts to develop a knowledge-based soci-
ety, paranormal beliefs remain common. For example, a 2005 poll indicated that 37% of
PLOS ONE | DOI:10.1371/journal.pone.0131378 July 15, 2015 1/16
OPEN ACCESS
Citation: Blanco F, Barberia I, Matute H (2015)
Individuals Who Believe in the Paranormal Expose
Themselves to Biased Information and Develop More
Causal Illusions than Nonbelievers in the Laboratory.
PLoS ONE 10(7): e0131378. doi:10.1371/journal.
pone.0131378
Editor: José César Perales, Universidad de
Granada, SPAIN
Received: July 16, 2014
Accepted: June 1, 2015
Published: July 15, 2015
Copyright: © 2015 Blanco et al. This is an open
access article distributed under the terms of the
Creative Commons Attribution License, which permits
unrestricted use, distribution, and reproduction in any
medium, provided the original author and source are
credited.
Data Availability Statement: All relevant data are
within the paper and its Supporting Information files.
Funding: This research was supported by Dirección
General de Investigación (Spanish Government;
Grant PSI2011-26965) and Departamento de
Educación, Universidades e Investigación (Basque
Government; Grant IT363-10).
Competing Interests: The authors have declared
that no competing interests exist.
Americans believed in "haunted houses" and 27% of UK citizens thought that it is possible to
communicate mentally with dead people [1]. In 2010, two in five Europeans claimed to be
superstitious according to the European Commission [2]. It remains unknown why many indi-
viduals maintain supernatural beliefs while others are skeptical.
Different related terms (e.g., paranormal, supernatural, magical, etc.) have been used to
refer to the same type of beliefs [3]. We will use the term "paranormal belief" as a general label.
Deficits in intelligence [4] and in critical/statistical thinking [5] have been proposed to underlie
individual differences in paranormal beliefs. However, these claims have been criticized on
methodological grounds [6], and empirical tests generated mixed or controversial results [7,8].
For instance, receiving courses on research methods or statistics, both of which imply critical
reasoning, does not affect by itself the endorsement of paranormal beliefs unless the course is
accompanied by specific guidance and tutorials to grant some degree of transfer [9,10].
On the other hand, paranormal beliefs correlate strongly with reported personal paranormal
experiences [11]. This finding suggests that a factor related to the way believers behave or inter-
pret reality, such as a type of generalized bias, leads to a belief in paranormal claims. Some
research lines assume that paranormal beliefs are the result of biased thinking, sometimes
related to personality traits. For example, Eckblad and Chapman [12] proposed that one of the
traits accompanying high schizotypy is the proneness to interpret personal experiences as para-
normal ("magical ideation"). More recent research [13] has gone further to conceptualize this
magical ideation bias, characteristic of the mentioned personality trait, as a tendency to make a
"false-positive" error when testing hypotheses, just like a scientist who commits a Type-I error.
Related works also drew a simile with a biased response criterion [14,15].
In a similar vein to the latter authors, it has been proposed that a contingency learning bias
underlies many, widely spread, irrational beliefs such as those involved in pseudomedicine or
pseudoscience [16]. Instead of focusing on individual differences in personality traits or psy-
chopathology, this contingency learning approach is based on a laboratory model that reveals
the bias in the general population. This contingency learning bias is known as "the illusion of
causality", or "causal illusion".
Causal illusions arise when people systematically interpret the ambiguity in random pat-
terns of stimuli as evidence of a causal relationship. For example, no objective evidence indi-
cates that wearing a lucky charm causes a desired outcome (e.g., winning a match), but
individuals may be inclined to interpret ambiguous information (e.g., cases in which one wears
the amulet and plays well) as compelling evidence favoring the cause-effect link. This bias
allows fast and efficient detection of causality based on co-occurrences, at the cost of develop-
ing illusory beliefs occasionally. While paranormal beliefs are typically measured using ques-
tionnaires, illusions of causality are studied using contingency learning experiments in which
participants see a series of occurrences of a potential cause and an outcome. Sometimes the tri-
als are predefined by the researchers, but normally, participants decide in which trials they
want to introduce the potential cause. In both variants of the task, the contingency between the
potential cause and the outcome is fixed by the experimenter to a null value (i.e., the participant
should conclude that no causal link exists), but the frequency of cause-outcome coincidences is
also manipulated to induce the illusory perception of a causal link [16,17].
We can draw a parallel between paranormal beliefs and causal illusions. In fact, paranormal
beliefs have been previously described as the result of a biased causal inference: Brugger and
Graves [13] conceive paranormal beliefs as a form of reasoning based on invalid assumptions
about causality (see also [12,15,18]). Moreover, evidence indicates that the illusion of control, a
type of illusion of causality in which the illusory cause is the participant's behavior, correlates
reliably with paranormal beliefs [19]. We suggest that surveys and questionnaires that measure
paranormal beliefs might reveal the results of illusions of causality that participants developed
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in the past via the same mechanisms that are studied in contingency learning experiments.
Consequently, the finding that some individuals exhibit more irrational beliefs than others, as
measured using questionnaires or other methods, might indicate not only that they developed
illusions in the past, but also that they have a stronger tendency to develop illusions of causal-
ity. If this is true, they should show a stronger vulnerability to laboratory-induced illusions of
causality, as compared to nonbelievers. A similar strategy for studying other proposed origins
of paranormal beliefs has been used by many researchers [1820].
We can further refine our prediction by postulating a candidate mechanism for the vulnera-
bility to develop causal illusions. The evidence to support our following proposal comes from
studies on paranormal beliefs and on contingency learning. First, Brugger and Graves [13]
found that participants with high scores on a magical ideation scale tested fewer hypotheses to
solve an experimental problem and relied on confirmatory evidence more often than partici-
pants with low scores. That is, they showed a prominent hypothesis-testing bias, sampling con-
firmatory information more often than disconfirmatory information. Then, returning to the
contingency learning literature, we point out that the bias in information sampling that Brug-
ger and Graves [13] reported is very similar to a very particular pattern of behavior that is often
reported in the contingency learning literature when the participant is given the opportunity to
decide in which trials to introduce the potential cause. This pattern of behavior implies observ-
ing more cause-present information than cause-absent information. In fact, we have docu-
mented a preference in participants to expose themselves to the potential cause very often [21].
That is, when asked to evaluate the relationship between a fictitious medicine and a frequent,
but unrelated, recovery from a fictitious disease, our participants exposed themselves predomi-
nantly to cause-present events (i.e., cases in which the medicine was administered), rather than
sampling equal numbers of cause-present and cause-absent events. This biased behavior is in
some way parallel to the one documented by Brugger and Graves [13] in paranormal believers.
In addition, the consequence of the biased behavior is similar to that of the positive testing
strategy [22], an strategy that involves performing tests that would yield a positive answer (i.e.,
recovery) if the initial hypothesis (i.e., that the medicine is effective) were correct, although in
our experiments the biased behavior might be occurring because of other reasons. For example,
the participants could just be trying to obtain the outcome (i.e., recovery from the disease),
which would not imply necessarily a hypothesis-testing strategy. Consequently, throughout
this paper we will use the term "biased exposure to information" to refer more neutrally to the
finding that people expose themselves more to cause-present cases than to cause-absent cases.
After all, regardless of the participants' motivation to behave in this way, the critical conse-
quence is their exposure to a biased sample of information extracted from all the potential
cases that can be observed.
Being exposed to biased information in this particular way has consequences in what refers
to causal judgments. We recently demonstrated that the degree of exposure to the potential
cause of an outcome influences illusions of causality [17]. In our studies, when the actual con-
tingency between the potential cause and the outcome was zero (i.e., when no causal relation-
ship should be derived from the available information), those participants showing a greater
exposure to cause-present cases developed a stronger illusion of causality. This, we suggest, is
mainly due to the following mechanisms: even when the actual contingency remains close to
zero, people tend (a) to expose themselves more often to cause-present trials, and (b) to put
more weight on those situations in which both the potential cause and the outcome co-occur
[23,24]. Therefore, a heavier weight of cause-outcome co-occurrences combined with the
already mentioned bias in the exposure to information (exposure to more cause-present cases)
would lead to a stronger overestimation of the contingency. Then, if believers in the paranor-
mal actually experience more cause-present cases in the contingency learning task (as we
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propose), the tendency of believers to develop stronger causal illusions would be partly medi-
ated by the bias in the information to which they expose themselves.
To sum up, we suggest that individual differences in the way people behave and expose
themselves to available information (like those observed by Barberia et al [21] and Brugger and
Graves [13] in their respective paradigms and literatures) leads to different proneness to
develop new illusions of causality in the laboratory (in fact, this relationship has been replicated
several times in what concerns contingency learning [17,25]). Then, those people with a
marked tendency to produce causal illusions would be probably more inclined to attribute the
occurrence of certain random events of their lives to spurious causes not only in the laboratory,
but also in contexts related to the paranormal (e.g., reading their horoscope in a newspaper).
These attributions would eventually crystallize as paranormal beliefs that can be measured in a
questionnaire. Unfortunately, in a typical laboratory setting, we are unable to test this latter
step directly because, according to the view we have just exposed, paranormal beliefs result
from a long previous history of experiences that is unique to each individual. This renders our
proposal that paranormal beliefs originate as causal illusions speculative. However, we can
readily measure currently held paranormal beliefs and examine how new illusions of causality
appear in a contingency learning task in the laboratory, to test whether paranormal believers
are more likely to develop illusions of causality. This has been the typical approach when study-
ing related hypotheses about the relationship between biases in causal reasoning and paranor-
mal beliefs [1820].
With exploratory aim, we also included three additional questionnaires to assess locus of
control, desire for control, and attitude towards science. Both the locus of control scale [26]
and the desire for control scale [27] have been reported to correlate with paranormal beliefs
(with believers showing more internal locus of control [2830] and stronger desire for control
[31]). In addition, an intuitive prediction is that both questionnaires would correlate with
causal illusion, because displaying an illusion in our contingency learning task amounts to
attributing control to produce outcomes to one's own decisions. Finally, we included the
attitude toward science scale [32] because we presumed that people with negative attitude
towards science would be more prone to have paranormal beliefs and also to fall prey to causal
illusions.
Method
Ethics statement
The ethical review board of the University of Deusto examined and approved the procedure
used in this experiment, as part of a larger research project (Ref: ETK-44/12-13). All partici-
pants signed a written informed consent form before the session.
Participants and Apparatus
Sixty-four psychology students from the University of Deusto (52 female), with a mean age of
18.69 years (SD = 1.45; range from 18 to 26) received extra credit for participating in this study.
The experiment was conducted in two separate computer classrooms simultaneously.
Procedure
The session included two activities: a computerized contingency learning task and a set of four
paper-and-pencil questionnaires. Approximately half of the participants in each room com-
pleted the contingency task prior to the questionnaires. The order was reversed for the remain-
ing participants. In addition, the order of the questionnaires was counterbalanced.
Paranormal Beliefs and Causal Illusions
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Contingency task. Similar to the conventional contingency learning task [33], participants
were asked to play the role of medical doctors and judge the ability of the fictitious medicine
Batatrim to cure the fictitious illness Lindsay Syndrome. The participants viewed a series of 40
medical records (one per trial) describing patients suffering from the illness on a computer
screen. In each trial, the participants decided whether or not to administer the medicine to the
current patient. After making their decision, the participants received feedback indicating
whether the patient was cured. We recorded the proportion of trials in which participants
chose to administer the medicine, P(Cause), as a measure of the tendency to bias the informa-
tion they sample during the task. After observing all 40 patients, the participants judged the
effectiveness of the medicine using a scale ranging from 0 (labeled as "ineffective") to 50
(labeled "moderately effective") to 100 (labeled "perfectly effective"). The effectiveness judg-
ment is actually an expression of the perceived strength of the causal relation between the med-
icine (i.e., the potential cause) and the healings (i.e., the outcome) [16,34,35]. The participants
then studied the ability of a second medicine (Dugetil), to cure Hamkaoman Syndrome using
the same procedure.
One of the medicines was completely ineffective, (i.e., cures were noncontingent on the par-
ticipants' decision to use the medicine: P(Outcome|Cause) = P(Outcome|¬Cause) = 0.75. In
contrast, the other medicine was highly effective (i.e., the contingency between medicine usage
and cures was positive: P(Outcome|Cause) = 0.75 and P(Outcome|¬Cause) = 0.125, making
the contingency 0.625. Given that judgments should be close to zero in the noncontingent
condition, if judgments were significantly higher than zero, that would indicate an illusion of
causality. Moreover, because judgments of contingency are typically accurate in nonzero con-
tingencies [36,33], the positive contingency condition served as an additional control to
distinguish between actual illusions of causality and indiscriminate high judgments in the non-
contingent condition. The order of presentation of the noncontingent and contingent condi-
tions was counterbalanced between subjects.
Questionnaires. Participants completed four questionnaires: the Spanish version of the
Revised Paranormal Belief Scale, R-PBS [37,38]; the Spanish version of the Locus of Control
scale [26,39]; Spanish version of the Desirability for Control scale [27,40]; and the Attitude
toward Science scale [32]. All scales except the R-PBS were included with exploratory
purposes.
The R-PBS is widely used to assess paranormal beliefs and consists of 30 statements (e.g.,
"Witches do exist.") covering a range of paranormal beliefs. Eight subscales were identified in
the Spanish version [38]: religion, psychic phenomena, witchcraft, traditional superstitions,
spiritualism, monsters, precognition, and extraterrestrial visitors. The statements are rated
by the participant on a scale from 1 (i.e., "Complete disagreement") to 7 (i.e., "Complete
agreement").
The Locus of Control scale [26,39] contains 23 items, each of them consisting of two state-
ments (labeled A and B), one representing an internal locus of control and another represent-
ing an external locus of control. For instance, Item 1 comprises the statements "A. Most sad
things that happen to people are due to bad luck" and "B. Bad things that happen to people are
due to their own mistakes". The participant must choose one of the statements for each item,
the one he or she feels more identified with. By counting the number of statements that repre-
sent internal and external control attitudes, one can compute an overall locus of control score
for the participant.
The Desire for Control scale [27,40] is a set of statements that must be assigned one value
from 1 ("Complete disagreement") to 5 ("Complete agreement"). The statements reference a
range of situations over which the person may like to exert control (e.g., "I prefer a job in which
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I have control over what I do and when I do it"). The higher the score in this questionnaire, the
stronger the desire for control of the participant.
Finally, the Attitude toward Science scale [32] is a collection of statements such as "Thanks
to science, we have a better world to live in", that must be rated on a 5-point scale from "Total
agreement" to "Total disagreement". The scale was included because we expected it to be nega-
tively correlated with paranormal beliefs and illusions of causality.
Results
(The dataset on which the following analyses were conducted is freely available as supporting
materials S1 Dataset).
We first report the mean P(Cause) for both contingency problems. In the noncontingent
problem, the participants decided to use the medicine frequently (M= 0.72, SD = 0.26), but less
often than in the contingent problem (M= 0.82, SD = 0.16), F(1, 63) = 9.56, p= 0.003, Z2
p=
0.13. This difference is discussed later.
Likewise, the mean effectiveness judgments measured in the noncontingent problem
(M= 54.42, SD = 25.56) were significantly lower than those measured in the contingent prob-
lem (M= 70.34, SD = 15.08), F(1, 63) = 25.45, p<0.001, Z2
p= 0.29. These results indicate that
the participants discriminated between the two contingencies and realized that the causal rela-
tionship was stronger in the contingent problem. In addition, they also show that the noncon-
tingent problem was perceived as contingent (mean judgments were higher than zero, t(63) =
17.04, p<0.001), indicating that a causal illusion developed.
Table 1 shows the correlation matrix between the scores obtained on the R-PBS and its sub-
scales and the variables assessed in the contingency task. The R-PBS score and several subscales
correlated positively with the judgments and the P(Cause) values obtained in the noncontin-
gent problem. Importantly, these scales did not correlate with any variable obtained in the con-
tingent problem (minimum p-value = 0.125) in which no illusion was expected.
We used the method proposed by Judd, Kenny and McClelland [41] to test the interaction
between R-PBS scores and problem (contingent vs. noncontingent) on the judgments, to find
that the difference between the two slopes was significant, β= 0.33, t(62) = 2.71, p= 0.009. This
interaction was then examined within each problem: the effect of the R-PBS on the judgments
was present in the noncontingent problem, β= 0.28, t(62) = 2.34, p= 0.02, but not in the con-
tingent problem, β= -0.06, t(62) = 0.50, p= 0.62. The same analyses were conducted on P
(Cause), showing similar results: a significant interaction between R-PBS and problem, β=
0.32, t(62) = 2.69, p= 0.009, with significant effect of R-PBS on P(Cause) in the noncontingent
problem, β= 0.39, t(62) = 3.31, p= 0.002 and nonsignificant effect in the contingent problem,
β= 0.11, t(62) = 0.91, p= 0.36. All these analyses align with the conclusions drawn from
Table 1, which suggested that paranormal beliefs were related to P(Cause) and judgments only
when the programmed contingency was zero.
Thus, participants with higher paranormal belief scores developed stronger causal illusions
in the noncontingent problem. Next, we examined the potential role of P(Cause) as a mediator
of this effect (see the mediational structure presented in Fig 1), so that people with more para-
normal beliefs would introduce the cause more frequently and this biased behavior would in
turn strengthen the illusion of causality. To this aim, we used the procedure described by
Baron and Kenny [42]. At a descriptive level, we show in Fig 2 that higher levels of P(Cause)
imply both higher judgments and higher scores in the R-PBS, which is consistent with the
mediation hypothesis. The indirect pathway between paranormal beliefs and judgments via P
(Cause) (Fig 1, paths a and b) was assessed in two steps. First, we found that paranormal beliefs
were a positive predictor of P(Cause), β= 0.39, t(63) = 3.31, p= 0.002 (i.e., the more beliefs the
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participants held, the more likely they were to use the ineffective medicine often during the
contingency learning task) (Fig 1, pathway a). Second, P(Cause) was a reliable predictor of the
causal illusion, even when we controlled for the effect of paranormal belief scores, β= 0.59, t
(62) = 5.33, p<0.001 (Fig 1, pathway b). Thus, the indirect effect of paranormal beliefs on judg-
ments via P(Cause) was significant (see Fig 2). When this indirect effect was partialled out, the
direct effect of paranormal beliefs on judgments disappeared, β= 0.06, t(63) = 0.52, p= 0.61
(Fig 1, pathway c), suggesting that the effect of paranormal beliefs on judgments was mediated
entirely by P(Cause).
Previous studies [17,43] have shown that, in this type of active tasks in which the participant
is free to decide how often and when to introduce the potential cause (i.e., the medicine), there
is some variability in the actual contingency that participants expose themselves to, and some-
times it could differ from the programmed contingency. However, the mean value of the actual
contingency is usually close to the programmed value. For completeness, we include the two
contingency tables with the mean frequencies of each type of trial the participants were
exposed to in each problem (see Fig 3). From these frequencies the actual contingency can be
computed using the ΔP rule. These actual contingencies were close to the programmed ones in
the noncontingent problem (M= 0.05, SD = 0.23) and in the contingent problem (M= 0.64,
SD = 0.14).
In addition, we report the observed correlations between the variables assessed in the con-
tingency task and the remaining exploratory questionnaires in Table 2. A positive attitude
towards science correlated negatively with judgments in both contingency problems, which
Table 1. Observed correlations between the variables assessed in the two contingency learning problems (columns) and the paranormal belief
scores (rows).
Noncontingent problem Contingent problem
Judgment P(Cause) Judgment P(Cause)
PBS-Total *0.284 **0.388 -0.064 0.115
(0.023) (0.002) (0.618) (0.365)
PBS-Religion 0.222 *0.316 -0.115 0.194
(0.078) (0.011) (0.365) (0.125)
PBS-Psi 0.106 *0.273 -0.106 -0.095
(0.403) (0.029) (0.406) (0.453)
PBS-Witchcraft *0.298 *0.305 0.054 0.043
(0.017) (0.014) (0.670) (0.737)
PBS-Superstition 0.105 0.162 -0.096 0.153
(0.409) (0.202) (0.450) (0.227)
PBS-Spiritualism 0.245 **0.395 -0.088 0.143
(0.051) (0.001) (0.490) (0.258)
PBS-Monsters 0.112 0.129 -0.023 0.154
(0.378) (0.308) (0.858) (0.225)
PBS-Precognition *0.262 *0.294 0.043 0.087
(0.036) (0.018) (0.736) (0.494)
PBS-ETs 0.187 0.162 0.020 0.002
(0.139) (0.200) (0.873) (0.987)
The top number in each cell corresponds to the Pearson's coefcient. Exact p-values are provided between brackets.
*p<0.05;
** p<0.01.
doi:10.1371/journal.pone.0131378.t001
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suggests that participants with positive attitude tended to be more skeptical even in the condi-
tion in which the contingency was positive. Both the Desire for Control and the Locus of Con-
trol scales failed to correlate with any variable in the contingency learning task.
Finally, the correlations between the scores obtained in these three exploratory question-
naires were not significant except for the following ones: Desire for Control was negatively
related to positive attitude towards science (r= -0.39, p= 0.002) and to Locus of Control (the
more internal the locus, the higher the desire for control; r= 0.99, p<0.001).
Discussion
We previously proposed [16] that the prevalence of paranormal beliefs in society is associated
to a general bias toward perceiving a causal link where no evidence exists (i.e., an illusion of
causality). Consistent with this hypothesis, the results of the current experiment revealed a sig-
nificant correlation between the previous paranormal beliefs of the participants and the magni-
tude of the illusion of causality that they developed in the laboratory, in a task that used
fictitious medicines and illnesses and was, therefore, unrelated to their beliefs. Importantly,
paranormal beliefs correlated with judgments only in the noncontingent problem, suggesting
that the ability to detect a causal relation when evidence exists (i.e., in the contingent problem)
was unaffected by paranormal beliefs.
We also measured the proportion of trials in which the participants decided to use the medi-
cine, P(Cause). Believers were more likely to use it. Thus, they acted in a way that exposed
them to cause-present trials more predominantly than did nonbelievers. This parallels previous
reports from a different research line and using a different experimental procedure, in which
paranormal believers sampled more confirmatory information [13]. However, with the present
study we cannot know the reasons why believers tended to expose themselves to high levels of
Fig 1. Mediational structure tested in the noncontingent condition. The total effect of the paranormal belief (R-PBS) scores on judgments (depicted as
pathway c) was partitioned into one indirect effect via P(Cause) (pathways a and b), and one direct effect (pathway c'), which is the result of discounting the
indirect effect. The results of this study suggest that prior paranormal beliefs increased the tendency to developnew causal illusions via the mediation of a
biased exposure to cause-present information.
doi:10.1371/journal.pone.0131378.g001
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P(Cause), it could be due to the same information sampling strategy reported by Brugger and
Graves [13], or simply a stronger tendency to persist in obtaining the outcome, for example.
The relationship between paranormal beliefs and judgments in the noncontingent task was
mediated entirely by this biased exposure to the available information. Thus, we propose that
believers developed stronger causal illusions due to their tendency to bias their behavior to
experience more cause-present cases. The idea that individual differences in personality
traits affect the development of causal illusions is not novel. For example, mildly depressed par-
ticipants are less likely to report illusions in a contingency learning paradigm [44,45].
This depressive realism effect appears to be mediated by the same information-exposure bias
described in this study (i.e., depressed people are less likely to act, and therefore they experience
less cause-present cases than do nondepressed people [45]).
Fig 2. Bubble chart showing the positive relationship between P(Cause) (horizontal axis), Judgments (vertical axis) and R-PBS scores (circle area)
in the noncontingent condition. A regression line was fitted to the P(Cause)-Judgments relationship (see main text).
doi:10.1371/journal.pone.0131378.g002
Paranormal Beliefs and Causal Illusions
PLOS ONE | DOI:10.1371/journal.pone.0131378 July 15, 2015 9/16
Admittedly, the mediational structure tested in the Results section is only one among the
many that can be hypothesized. We assumed that the participants' paranormal beliefs were a
preexisting condition instead of being the outcome of the study, whereas the P(Cause) and the
judgments were produced in a definite moment in the laboratory. The performance measured
in the contingency learning task was in fact affected by individual differences in paranormal
beliefs: believers tended to sample more cause-present trials and showed greater illusions dur-
ing the experiment. Therefore, we were not testing how paranormal beliefs originated in our
participants. Instead, we tested the hypothesis (suggested in the literature: [13,16,19]) that
paranormal believers would be more prone to the illusion of causality, and that the mechanism
mediating this proneness would be a bias in the way they behave and, therefore, a bias in the
information they are exposed to, so that more cause-present than cause-absent cases are expe-
rienced. However, although we do not need to assume that all paranormal beliefs originate as
causal illusions, it seems sensible to propose that those individuals with greater vulnerability to
causal illusions developed this type of illusions in the past, in other situations that, unlike our
laboratory settings, are related to paranormal phenomena (e.g., when reading their horoscope
in a newspaper). Then, this would reveal as a correlation between paranormal belief and causal
illusion in our experiment. In fact, previous works resting on the hypothesis that paranormal
beliefs are produced by certain traits (e.g., deficits in the ability to make probabilistic judg-
ments) used designs similar to ours, in which paranormal beliefs are measured and then an
experimental task is conducted [18].
Fig 3. Mean frequencies of each trial type to which the participants exposed themselves in each condition. Standard deviations are provided between
brackets.
doi:10.1371/journal.pone.0131378.g003
Table 2. Observed correlations between the variables assessed in the two contingency learning problems (columns) and the three exploratory
questionnaires (rows).
Noncontingent problem Contingent problem
Judgment P(Cause) Judgment P(Cause)
Desire for control 0.178 0.007 0.173 -0.011
(0.158) (0.958) (0.172) (0.934)
Attitude toward science *-0.278 -0.043 **-0.468 -0.037
(0.026) (0.733) (<0.001) (0.773)
Locus of Control (the more positive, the more internal) 0.182 0.000 0.174 -0.014
(0.150) (0.998) (0.169) (0.911)
The top number in each cell corresponds to the Pearson's coefcient. Exact p-values are provided between brackets.
*p<0.05;
** p<0.01.
doi:10.1371/journal.pone.0131378.t002
Paranormal Beliefs and Causal Illusions
PLOS ONE | DOI:10.1371/journal.pone.0131378 July 15, 2015 10 / 16
It is worth noting that the medical scenario in the contingency task that we used was unre-
lated to the paranormal domain. Believers still biased the information they observed in the
noncontingent problem, so that they were exposed to more cause-present than cause-absent
cases, and developed a causal illusion. This finding suggests that the observed bias is a general
bias that is not restricted to the paranormal domain. It seems that believers in the paranormal
are biased in a way that makes them more likely to develop illusions in general (i.e., not only
those related to paranormal beliefs). This finding may have important societal implications, as
the illusion of causality is proposed to underlie other problems, including the spread of pseudo-
science, vulnerability to advertisement, social stereotypes, and intolerance [46].
Another point that needs clarification is the high proportion of cause-present cases, P
(Cause), that was observed in the contingent problem as compared to the noncontingent prob-
lem, irrespective of the paranormal beliefs. According to previous studies [21], it is actually
very common to find higher probability of cause-present trials when the programmed contin-
gency is positive. In addition, we do not necessarily interpret this finding as the result of the
same type of bias that we reported in the noncontingent scenario. First, because the desired
outcome (i.e., recovery from the disease) was contingent on the use of the medicine in this
problem, this behavior of using the medicine was reinforced more frequently than its counter-
part (i.e., not using the medicine), and thus it became prevalent. Second, the contingent prob-
lem is not as ambiguous as the noncontingent problem: once the contingency is learned by the
participant (i.e., they realize that the medicine actually works), the most probable behavior is to
use the medicine frequently to produce the positive outcome (i.e., healing the patients) as often
as possible. These two conditions are not met in the noncontingent problem, in which the
desired outcome was not produced by the participants' behavior, and still they preferred to use
the medicine with high probability, and even more often when they held paranormal beliefs.
As commented in the Results section, despite having some variability in the probability with
which the participants decided to use the medicine, the actual values of the contingencies expe-
rienced by them were on average very similar to the programmed values (Fig 3). This is a com-
mon finding in the literature of contingency learning [17,43]. Given that our participants were
actually exposed to a contingency close to zero in the noncontingent problem, how could they
exhibit causal illusions? The way in which most theories explain causal illusions when actual
contingency is zero implies the assignment of different weights to each trial type. It is often
reported that participants give more importance to those trial types in which the potential
cause and the outcome coincide [23,24], and this so-called differential cell weighting could
account for the illusion of causality [24,47]. Interestingly, weighting differently each type of
trial is a rational strategy in many causal inference situations, but the specific rank of trial
weights depends on further factors [48,49]. In any case, judgments given in contingent situa-
tions (either positive or negative) tend to be close to their actual value, as in our contingent
problem, or at least tend to show the correct tendency between different contingency levels. It
is mostly under certain conditions of noncontingency (e.g., high probability of outcome-pres-
ent trials, and high probability of cause-present trials) that participants produce large overesti-
mations, or causal illusions, like those we reported here. Note that, because the tendency to
weight the trial types differently is a basic phenomenon, the causal illusion appears in the gen-
eral population (e.g., Internet users, college students, etc. [50]) just as optical illusions, as we
advanced in the Introduction. In addition, it becomes more prominent in those people with
tendency to expose themselves to a disproportionate number of cause-present trials, as is the
case of nondepressed participants [45], people instructed to obtain as many outcomes as they
can [25], and, according to the current study, paranormal believers.
Although both the tendency to believe in actually nonexistent causal links and to bias the
information-exposure behavior would seem problematic traits for any organism, they are in
Paranormal Beliefs and Causal Illusions
PLOS ONE | DOI:10.1371/journal.pone.0131378 July 15, 2015 11 / 16
fact adaptive in most circumstances, particularly in those resembling our ancestral way of life:
after all they seem to have been favored by natural selection during our evolutionary history. In
what concerns the bias to attribute random co-occurrence of events to cause-effect relation-
ships (illusion of causality), some researchers have pointed out the beneficial role of this kind
of illusions in the adherence of behaviors [51]. For instance, early farming cultures were able
neither to produce nor to understand the conditions for the occurrence of important events
such as rain. However, the development of superstitions revolving around these events proba-
bly helped our ancestors to not give up and persist trying and cultivating their crops. Another
reason why causal illusions are adaptive sometimes is that they frequently represent the least-
costly mistake [25,52]. Taking an inoffensive branch for a snake would lead to unnecessarily
flee and waste energy, whereas making the opposite mistake might result in death. In these
ancestral environments, attributing random patterns to actual causation is often harmless,
compared to the consequences of missing a real causal link. Arguably, this advantage of the
biased causal reasoning is substantially reduced, or even reversed, in other scenarios. In today's
society, important decisions, such as determining which treatment we undergo to cure a dis-
ease, should be based on scientific evidence rather than on our natural tendency to identify
accidental coincidences between taking the treatment and symptom remission as evidence for
the effectiveness of the treatment. Thus, the same biases that help us make quick decisions
today and that were valuable tools to survive in the past are sometimes harmful, given that they
can lead to dangerous practices (e.g., taking a useless medicine instead of an effective one).
Some researchers favor this viewpoint according to which superstitions and other beliefs are
natural, unavoidable by-products of an otherwise adaptive learning strategy, which in fact
keeps being adaptive in many situations but leads to dangerous consequences in many other
ones [53]. The challenge is then to find the optimum level of flexibility to reach a balance
between quick learning and caution in judging causal relationships.
There are two methodological points that are worth being commented. In the contingency
learning literature, learning is assessed by means of judgments collected at the end of the train-
ing session, just as we did in our study. Available evidence indicates that the wording of the
question can affect substantially the judgment given by the participant [54,55]. In our case, we
chose to formulate the question in terms of effectiveness (i.e., how effective the medicine was to
heal the patients), instead of in terms of causality (i.e., how likely the medicine was the cause of
the healings), because this wording seems easier to understand, more intuitive for participants,
and more ecological, while retaining basically the same meaning. In fact, judgments of effec-
tiveness are more common in the illusion of control literature, but they are also present in
causal learning experiments [34,35], even if they are referred to as "causal judgments". At least
one study compared the two types of question, effectiveness and causality, and found that they
were not significantly different from each other, showing the same basic effect of causal illusion
[16]. Thus, not only the effectiveness question is conceptually similar to the causal question,
but it yields similar results empirically.
The second concern about the judgment we used to assess the illusion refers to the potential
confound between the causal strength perceived by the participants and their confidence in
their judgments. This possibility is sometimes called "the conflation hypothesis" [56], and to
some extent it seems an unavoidable problem: even in experiments specifically tailored to
address this issue, still some participants appear to contaminate their causal judgment by
expressing their confidence [56]. Consequently, the potential conflation affects to most of the
literature in the causal learning field. In our current study, if participants really confounded
effectiveness and confidence in their judgments, that would be problematic only if confidence
varied systematically with paranormal beliefs. In addition, when we asked the judgments, we
labeled not only the ends of the scale, but also the midpoint, 50, as "moderately effective",
Paranormal Beliefs and Causal Illusions
PLOS ONE | DOI:10.1371/journal.pone.0131378 July 15, 2015 12 / 16
which should help participants make the right interpretation. A possible follow-up for our
study would explore different judgment scales, such as bidirectional scales, that are also
affected by the potential conflation but have a different meaning for their midpoint.
As reported above, in addition to the R-PBS, other questionnaires were included in the
study to complement the main variables of interest. First, the locus of control scale [26] was
expected to correlate with the judgments in the noncontingent problem, such that the more
internal the locus, the stronger the illusion. We found no evidence of correlation between the
locus of control and any variable assessed during the contingency learning task. In addition,
previous studies [29,30] reported correlations between superstitious beliefs as assessed by the
R-PBS and locus of control, which we failed to replicate. Second, the desire for control scale
[27] was included because it measures a construct similar to the locus of control. In fact, both
correlated in our study (the more internal the locus, the higher the desire of control), but
again this questionnaire failed to correlate with P(Cause) and judgments, and also with the
paranormal beliefs (thus, we failed to replicate this finding that has been reported in the litera-
ture [31]).
The reasons for including the questionnaire of attitude towards science was that, according
to our framework, many pseudoscientific beliefs are associated to causal illusions [16]; there-
fore, positive attitude towards science would correlate with more accurate perception of causal-
ity. Actually, participants with a positive attitude towards science judged the fictional medicine
less effective in both contingency problems. This result could be caused by these participants
generalized skepticism, even when the available evidence supports a causal relationship. Thus,
on the basis of this datum, we suggest that holding a positive attitude towards science does not
improve discrimination between contingent and noncontingent problems, but rather promotes
overall conservative judgments.
Conclusions
In conclusion, believers in the paranormal showed a behavioral bias that produced high expo-
sure to cause-present information and development of new causal illusions of arbitrary content
in the laboratory. The results presented here suggest that beliefs in the paranormal are accom-
panied by a biased exposure to available information, which might fuel causal illusions.
Supporting Information
S1 Dataset. Dataset containing the data used in the study.
(XLS)
Author Contributions
Conceived and designed the experiments: FB IB HM. Performed the experiments: FB IB. Ana-
lyzed the data: FB IB. Wrote the paper: FB IB HM.
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... Like pseudoscience, they are not supported by empirical evidence under controlled conditions (Wilson, 2018). The prevalence of beliefs in paranormal phenomena in society is associated with a general bias towards the perception of causal links where there is no hard evidence, which Blanco et al. (2015) called illusion of causality. Aarnio and Lindeman (2005) showed that as the educational level increases these paranormal beliefs decrease. ...
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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.
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Prior knowledge has been shown to be an important factor in causal judgments. However, inconsistent patterns have been reported regarding the interaction between prior knowledge and the processing of contingency information. In three studies, we examined the effect of the plausibility of the putative cause on causal judgments, when prior expectations about the rate at which the cause is accompanied by the effect in question are explicitly controlled for. Results clearly show that plausibility has a clear efect that is independent of contingency information and type of task (passive or active). We also examined the role of strategy use as an individual difference in causal judgments. Specifically, the dual-strategy model suggests that people can either use a Statistical or a Counterexample strategy to process information. Across all three studies, results showed that Strategy use has a clear effect on causal judgments that is independent of both plausibility and contingency.
... In a recent integrative theoretical framework, Rizeq et al. (2021) suggested to consider conspiracy and paranormal beliefs and anti-science attitudes as three components of a higher order psychological factor termed as "contaminated mindware". According to this approach, specific cognitive processing styles result in a contaminated mindware, such as a biased perception of probability and causality (e.g., perceiving meaningful patterns or causality in unrelated events), low levels of reality testing and open-minded thinking (e.g., low ability or motivation to critically test the plausibility of one's beliefs), ontological confusions (e.g., believing that lifeless natural objects are animate or that thoughts can be manifested as physical forces), and related to all these aspects, an over-reliance on intuitive-experiential over rational processing in judgments and decision making (e.g., Betsch et al., 2020;Blackmore & Moore, 1994;Blanco et al., 2015;Brugger & Graves, 1997;Čavojová et al., 2020;Denovan et al., 2018Denovan et al., , 2020Drinkwater et al., 2012;Foster & Kokko, 2009;Irwin, 2009;Leonard & Williams, 2019;Lindeman & Aarnio, 2007;Matute et al., 2011;Musch & Ehrenberg, 2002;Pennycook et al., 2012;Rizeq et al., 2021;Ståhl & van Prooijen, 2018;van Prooijen, Douglas, et al., 2018). ...
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The global coronavirus (COVID-19) pandemic sparked a great interest in psychological factors that determine or explain peoples' responses to the novel threatening situation and the preventive measures (e.g., wearing masks, social distancing). In this study, we focused on contaminated mindware (conspiracy and paranormal beliefs) and investigated its relationship with both acceptance of and adherence to COVID-19 preventive measures, along with other variables from the domains of emotion (trait anxiety, fear), traditional personality traits (Big 5, locus of control, optimism/pessimism) and motivation (self-control, dispositional regulatory focus). A total of 22 variables were measured in an online survey (N = 374) that took place during the second wave of COVID-19 (Nov. 2020 - March 2021) in Switzerland. Of all variables, the endorsement of specific COVID-19 conspiracy beliefs was most strongly associated with lower acceptance and adherence to the preventive measures, together with mistrust in science and a more right-wing political orientation. In contrast, fear of COVID-19 and prevention regulatory focus were positively associated with acceptance and adherence. Our results therefore highlight the importance of fighting (conspiratorial) misinformation and of increasing the perceived credibility of science in reducing the spread of the coronavirus. Moreover, when acceptance was used as predictor for adherence, agreeableness and dispositional prevention regulatory focus still explained unique variance in adherence, suggesting that such personality and motivational variables play an important role in adhering and regulating preventive behaviour independent from the attitude towards the preventive measures themselves.
... In these cases, then, it seems personality factors may be a stronger determinant of causal beliefs. Within the contingency learning literature, paranormal belief has been linked to heightened illusory causation, where participants who report strong beliefs in the paranormal are more likely to expose themselves to cause-present information [35], as well as lower signal-detection criterion-strong believers in the paranormal were more likely to draw associations between unrelated stimuli [36] or perceived there to be a causal agent for events where there is none [37]. Taken together, it is possible that when there is insufficient direct experience with the putative cause and outcome for accurate contingency estimation, participants who are susceptible to biased thinking are more likely to expose themselves to confirmatory evidence and/or interpret ambiguous events as evidence for the causal relationship, thus they develop more positive opinions about these beliefs. ...
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Beliefs about cause and effect, including health beliefs, are thought to be related to the frequency of the target outcome (e.g., health recovery) occurring when the putative cause is present and when it is absent (treatment administered vs. no treatment); this is known as contingency learning. However, it is unclear whether unvalidated health beliefs, where there is no evidence of cause–effect contingency, are also influenced by the subjective perception of a meaningful contingency between events. In a survey, respondents were asked to judge a range of health beliefs and estimate the probability of the target outcome occurring with and without the putative cause present. Overall, we found evidence that causal beliefs are related to perceived cause–effect contingency. Interestingly, beliefs that were not predicted by perceived contingency were meaningfully related to scores on the paranormal belief scale. These findings suggest heterogeneity in pseudoscientific health beliefs and the need to tailor intervention strategies according to underlying causes.
... In a recent integrative theoretical framework, Rizeq et al. (2021) suggested to consider conspiracy and paranormal beliefs and anti-science attitudes as three components of a higher order psychological factor termed as "contaminated mindware". According to this approach, specific cognitive processing styles result in a contaminated mindware, such as a biased perception of probability and causality (e.g., perceiving meaningful patterns or causality in unrelated events), low levels of reality testing and open-minded thinking (e.g., low ability or motivation to critically test the plausibility of one's beliefs), ontological confusions (e.g., believing that lifeless natural objects are animate or that thoughts can be manifested as physical forces), and related to all these aspects, an over-reliance on intuitive-experiential over rational processing in judgments and decision making (e.g., Betsch et al., 2020;Blackmore & Moore, 1994;Blanco et al., 2015;Brugger & Graves, 1997;Čavojová et al., 2020;Denovan et al., 2018Denovan et al., , 2020Drinkwater et al., 2012;Foster & Kokko, 2009;Irwin, 2009;Leonard & Williams, 2019;Lindeman & Aarnio, 2007;Matute et al., 2011;Musch & Ehrenberg, 2002;Pennycook et al., 2012;Rizeq et al., 2021;Ståhl & van Prooijen, 2018;van Prooijen, Douglas, et al., 2018). ...
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Since the outbreak of the coronavirus disease (COVID-19), there is an exploding interest in psychological factors that determine how people respond to the novel threatening situation and the preventive measures. In the present research, we assessed the role of a comprehensive list of 22 psychological variables from the domain of emotion (trait anxiety, fear of COVID-19, fear of death), cognition (COVID-19 specific and general conspiracy beliefs, paranormal beliefs, mistrust in science, faith in intuition), motivation (self-control, regulatory focus) and more traditional personality traits (Big 5, locus of control, optimism/pessimism) on the acceptance and adherence to the preventive measures. The survey took place during the second wave in Switzerland (Nov. 2020-March 2021; N = 374). Fear of COVID-19, prevention regulatory focus and social norm compliance were positively associated with both acceptance and adherence to the preventive measures, while the opposite was true for COVID-19 specific conspiracy beliefs, mistrust in science, conspiracy mentality, and paranormal beliefs. From these latter variables, mistrust in science was still a significant predictor when COVID-19 specific conspiracy beliefs was considered as mediator. Interestingly, none of the Big 5 variables was associated with acceptance. However, when controlling for acceptance, agreeableness and openness (together with self-control and prevention regulatory focus) were positively associated with adherence. Finally, more right-wing political orientation was associated with lower acceptance and adherence to the preventive measures. Our results highlight the importance of fighting (conspiratorial) misinformation and increasing the perceived credibility of science in reducing the spread of the coronavirus. Furthermore, self-control and prevention regulatory focus seem important motivational aspects for the actual preventive behaviour.
... Given our premise that the supernatural does not exist, it seems reasonable to assume that such believers have misinterpreted certain stimuli and that their interpretation of the event is crucial in shaping their belief. Indeed, a tendency to see causal relationships where there are none is common (Blanco et al., 2015;Griffiths et al., 2019;Matute et al., 2011). However, believers appear to be more biased to interpret random patterns as signals of supernatural causes, presenting more misidentifications or false alarms (events mislabeled as supernatural) than non-believers, and being more confident in their interpretations, responding faster in the face of unclear information, whereas disbelievers are more careful, less confident and slower, giving fewer errors (Simmonds- Moore, 2014;Van Elk, 2015). ...
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Supernatural fears, although common, are not as well-understood as natural fears and phobias (e.g., social, blood, and animal phobias) which are prepared by evolution, such that they are easily acquired through direct experience and relatively immune to cognitive mediation. In contrast, supernatural fears do not involve direct experience but seem to be related to sensory or cognitive biases in the interpretation of stimuli as well as culturally driven cognitions and beliefs. In this multidisciplinary synthesis and collaborative review, we claim that supernatural beliefs are “super natural.” That is, they occur spontaneously and are easy to acquire, possibly because such beliefs rest on intuitive concepts such as mind-body dualism and animism, and may inspire fear in believers as well as non-believers. As suggested by psychological and neuroscientific evidence, they tap into an evolutionarily prepared fear of potential impending dangers or unknown objects and have their roots in “prepared fears” as well as “cognitively prepared beliefs,” making fear of supernatural agents a fruitful research avenue for social, anthropological, and psychological inquires.
... More generally, the tendency to jump to conclusions implies a reduced experience with causes and effects, hence compromising the representativeness and quality of the information that is used for causal inference. 49,68,69 and these beliefs have also been found associated to the tendency to jump to conclusions 14,18,19 . ...
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Previous research proposed that cognitive biases contribute to produce and maintain the symptoms exhibited by deluded patients. Specifically, the tendency to jump to conclusions (i.e., to stop collecting evidence soon before making a decision) has been claimed to contribute to delusion formation. Additionally, deluded patients show an abnormal understanding of cause-effect relationships, often leading to causal illusions (i.e., the belief that two events are causally connected, when they are not). Both types of bias appear in psychotic disorders, but also in healthy individuals. In two studies, we test the hypothesis that the two biases (jumping to conclusions and causal illusions) appear in the general population and correlate with each other. The rationale is based on current theories of associative learning that explain causal illusions as the result of a learning bias that tends to wear off as additional information is incorporated. We propose that participants with higher tendency to jump to conclusions will stop collecting information sooner in a causal learning study than those participants with lower tendency to jump to conclusions, which means that the former will not reach the learning asymptote, leading to biased judgments. The studies provide evidence in favour that the two biases are correlated but suggest that the proposed mechanism is not responsible for this association.
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Possible reasons for belief in the paranormal are discussed and two hypotheses suggested. The first -that some belief in psi arises from misjudgements of probability - predicts more errors in probability tasks among believers (sheep) than disbelievers (goats). In two experiments subjects completed various computer-controlled probability tasks. In the first sheep performed worse than goats on most tasks and were significantly worse at responding appropriately to changes in sample size. In Expt 2 sheep were significantly worse at questions involving sampling. The second hypothesis is that some belief in psi arises from an illusion of control. Previous studies have shown a greater illusion of control among sheep in psi tasks (even when no psi occurs). We predicted the same effect in tasks not overtly involving psi. This was confirmed in Expt 3, using a computer-controlled coin-tossing task. Half the trials allowed for subject control of the coin and half did not. Sheep felt that they were exercising greater control than goats (irrespective of actual control) but estimated they had scored fewer hits. This could be explained if sheep misjudged chance scoring level. This was tested and sheep were found to underestimate chance scores. This ‘chance baseline shift’ could underlie the illusion of control and the belief in psi. No evidence of psi was found.
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This essay presents the central results of a representative survey carried out by the Institute for Frontier Areas of Psychology and Mental Health at Freiburg/Germany. We report both qualitative results and descriptive statistics based on a sample of over 1500 residents of the Federal Republic of Germany who were questioned about their attitude towards exceptional experiences. Surprisingly, large parts of the German population are quite open-minded about exceptional experiences, and more than half of the respondents even report such experiences personally. It is conspicuous that both the belief in exceptional experiences and personal accounts of such experiences refer over-abundantly to young people. In a follow-up interview more than 200 subjects were questioned, this time in detail, about their personal experiences. There are clear indications that revealing personal experiences is mostly not seen as problematic.
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It is clear that a wide range of situations exist that can potentially lead people to believe that they have experienced the paranormal when in fact they have not. The question regarding possible differences between believers and non-believers in the paranormal in terms of proneness to cognitive biases can now be answered rather more definitively than has been possible previously. Believers in the paranormal tend to be poorer at syllogistic reasoning, have a more distorted concept of randomness leading them to see meaning where there is none, are more susceptible to experiencing anomalous sensations and are, in certain circumstances, more suggestible. Memory biases in the accuracy of eyewitness testimony for ostensibly paranormal events have also often been reported, and evidence is beginning to accumulate that believers may be more prone to false memories.