Bias versus bias: Harnessing hindsight to reveal paranormal belief change beyond demand characteristics

Psychological change is difficult to assess, in part because self-reported beliefs and attitudes may be biased or distorted. The present study probed belief change, in an educational context, by using the hindsight bias to counter another bias that generally plagues assessment of subjective change. Although research has indicated that skepticism courses reduce paranormal beliefs, those findings may reflect demand characteristics (biases toward desired, skeptical responses). Our hindsight-bias procedure circumvented demand by asking students, following semester-long skepticism (and control) courses, to recall their precourse levels of paranormal belief. People typically remember themselves as previously thinking, believing, and acting as they do now, so current skepticism should provoke false recollections of previous skepticism. Given true belief change, therefore, skepticism students should have remembered themselves as having been more skeptical than they were. They did, at least about paranormal topics that were covered most extensively in the course. Our findings thus show hindsight to be useful in evaluating cognitive change beyond demand characteristics.
Psychology and its allied disciplines have long struggled to accurately assess change, whether that ostensible change results from maturation, senescence, laboratory experimental manipulations, psychotherapeutic techniques, community interventions, or educational programs (see, e.g., Cronbach & Furby, 1970; Hertzog & Nesselroade, 2003; Lord, 1956, 1967; Nesselroade, Stigler, & Baltes, 1980; Rubin, 1974). Of course, in contexts in which the desired change is entirely subjective—as is the case with attitudes, beliefs, cognitions, evaluations, or emotional states—the risks of misidentifying or misinterpreting change will only increase, since subjects’ self-reports may be biased, distorted, or erroneous (see, e.g., Conway & Ross, 1984; Festinger, 1957; Greenwald, Spangenberg, Pratkanis, & Eskenazi, 1991; Hoogstraten, 1979; Kirsch, 1985; Lewinsohn & Rosenbaum, 1987; Loftus, 1979; H. Markus & Kunda, 1986; Orne, 1962; Wilson & Brekke, 1994). Researchers must therefore develop statistical and methodological tools to help discriminate real from illusory change. The present study demonstrated a seemingly paradoxical approach, whereby a powerful cognitive bias was strategically deployed as a means to counter another, especially formidable bias that plagues assessment of subjective change —here, in the context of an educational intervention designed to affect undergraduates’ beliefs.

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By: Michael J. Kane, Tammy J. Core R. Reed Hunt

Made available courtesy of the Psychonomic Society:


Critical thinking ability and belief in the paranormal

Andreas Hergovich a,*, Martin Arendasy a
a Institute of Psychology of the University of Vienna, Liebigg. 5, 1010 Vienna, Austria
Received 10 March 2004;received in revised form 30 September 2004;accepted 1 November 2004
Available online 2 February 2005

A study was conducted to assess the relationship between critical thinking and belief in the paranormal. 180 students from three departments (psychology, arts, computer science) completed one measure of reasoning, the Paranormal Belief Scale (Tobacyk & Milford, 1983), and a scale of paranormal experiences. Half of the subjects filled out the Cornell Critical Thinking Test (Ennis & Millmann, 1985) and the Watson–Glaser Critical Thinking Appraisal (Watson & Glaser, 2002), respectively. The results show no significant correlations between critical thinking and paranormal belief or experiences. Reasoning ability, however, had a significant effect on paranormal belief scores, but not on paranormal experiences. Subjects with lower reasoning ability scored higher on Traditional Paranormal Belief and New Age Philosophy than did subjects with higher reasoning abilities. Results suggest that those who have better reasoning abilities scrutinise to a greater extent whether their experiences are sufficient justification for belief in the reality of these phenomena.
2004 Elsevier Ltd. All rights reserved.
Keywords: Critical thinking ability;Paranormal belief;Paranormal experiences;Reasoning ability

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Reasoning in believers in the paranormal

ABSTRACT Reasoning biases have been identified in deluded patients, delusion-prone individuals, and believers in the paranormal. This study examined content-specific reasoning and delusional ideation in believers in the paranormal. A total of 174 members of the Society for Psychical Research completed a delusional ideation questionnaire and a deductive reasoning task. The reasoning statements were manipulated for congruency with paranormal beliefs. As predicted, individuals who reported a strong belief in the paranormal made more errors and displayed more delusional ideation than skeptical individuals. However, no differences were found with statements that were congruent with their belief system, confirming the domain-specificity of reasoning. This reasoning bias was limited to people who reported a belief in, rather than experience of, paranormal phenomena. These results suggest that reasoning abnormalities may have a causal role in the formation of unusual beliefs. The dissociation between experiences and beliefs implies that such abnormalities operate at the evaluative, rather than the perceptual, stage of processing.

Reasoning in believers in the paranormal.

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How psychotic-like are paranormal beliefs?

Background and objectives:

Paranormal beliefs and Psychotic-like Experiences (PLE) are phenotypically similar and can occur in individuals with psychosis but also in the general population; however the relationship of these experiences for psychosis risk is largely unclear. This study investigates the association of PLE and paranormal beliefs with psychological distress.


Five hundred and three young adults completed measures of paranormal beliefs (Beliefs in the Paranormal Scale), psychological distress (General Health Questionnaire), delusion (Peters et al. Delusions Inventory), and hallucination (Launay-Slade Hallucination Scale) proneness.


The frequency and intensity of PLE was higher in believers in the paranormal compared to non-believers, however psychological distress levels were comparable. Regression findings confirmed that paranormal beliefs were predicted by delusion and hallucination-proneness but not psychological distress.


The use of a cross-sectional design in a specific young adult population makes the findings exploratory and in need of replication with longitudinal studies.

The predictive value of paranormal beliefs and experiences for psychosis may be limited; appraisal or the belief emotional salience rather than the belief per se may be more relevant risk factors to predict psychotic risk.


Matteo Cella a,b,*, Marcello Vellantec, Antonio Pretic,d
a Institute of Psychiatry, King’
s College London, London SE5 8AF, UK
b Department of Clinical, Educational & Health Psychology, University College London, UK
c Department of Clinical Psychology, University of Cagliari, Italy
d Centro Medico Genneruxi, via Costantinopoli 42, 09129 Cagliari, Italy


The Logic Paradox: Hostages of Belief

In recent years the primary focus of my research has been on human perception.  After all our perceptions are key, not only to the way we interpret the world around us, but also to the decisions we make and the things we believe.  Understanding the fallibility and  strengths of the way humans ‘digest’ their experiences is vital to my research in mysterious phenomena.

Part of the basic process in understanding human perception is simply observing.  Watching how individuals interpret various conditions or events and then comparing those observations with published research results from respected and accomplished scientists.  That basic process alone can be fascinating.   Over time it’s easy to become engulfed  in the subject and recognize the incredible power of bias and the limiting input of a singular perspective.  No one, including myself, is free from the power of this unyielding variable, however it does seem to affect some more than others.

Throughout my years of research, I have noticed a pattern. It’s nothing new really, but it seems as though people (mostly those of a spiritual nature)  tend to adopt concepts that seem “logical” based on their own personal experience rather than what seems “illogical” based on factual information.  It’s not really that difficult to understand why, after all if you’ve  “heard” voices in your bedroom, it seems like an easy assumption that someone or something is/was there speaking.

But very often the human mind is lazy, unwilling to invest its time in considering options that go beyond easily explainable occurrences.  If the simpler explanations (i.e. Another person in the room, Radio on, Television on, person outside) can be ruled out, they will accept their initial analysis and ignore other more elaborate possibilities such as psychological issues, neurological issues or even simple misinterpretations.

It’s easier for us as humans to believe our first impressions and so we tend to “accentuate the positive”, confirming our experiences even if it goes against the majority of demonstrated research or even if it seems too wild to be true.

It seems to me there’s a blinding element to this biased human perception process that seems to hinder a person’s ability to reason.  They are in essence a hostage of their own beliefs and some tend to be trapped into ideas that resemble the erratic rantings of psychotic behavior.

In 2008 I spoke to a woman in Western Massachusetts who claimed she was being tormented by demons. She claimed to hear them walking in her attic and was adamant that they were watching her at all hours of the night, waiting for the right time to kill her.  The woman’s husband was concerned and while he was not as sold on the idea of a spiritual entity he often humored her by attempting rituals to “scare” the beings away.

Later that same year I spoke to a woman who was subsequently diagnosed with a mental disorder called paranoid schizophrenia. She claimed that the police were building missiles on the hill in her home town and that all of her neighbors were breaking into her house every night to watch her sleep. She claimed that they were planning to do something awful to her.

Both women were adamant about their claims. These were sincere people who truly felt these things were happening in spite of the real world logic that discounted such fantastic claims. Other than the component of demons vs humans, what difference is there between these two claims?  Why is the highly irrational fear of stalking humans with bad intentions considered eligible for psycho-analysis but the equally irrational fear of attacking demons less concerning?

It is my opinion that the answer lies with the nature of each claim and the public perception of them.  The element of spirituality is often regarded as a type of religious belief and to suggest psychotic behavior in response to spirit based perspective would be both insulting and politically incorrect (imagine the religious consequences if this were accepted), so the subject becomes taboo and the experiences continue.

Of course this is not to suggest that all paranormal experiences are the result of a mental illness, but it does seem as though there are elements within our own psychological processes that maintain and foster our beliefs, even in the face of opposing logic. This restrictive behavior acts as a barricade, hindering our ability to logically process any new information that opposes our beliefs.

Perhaps discovery is best served not by finding new things, but by removing old ones.

Supporting research:

First Impressions Matter: A Model of Confirmatory Bias*
Confirmation Bias in Complex Analyses

How psychotic-like are paranormal beliefs?

Hallucination: A Normal Phenomenon?

A superb article Posted by Dartmouth University Journal of Science / In Fall 2009 / November 21, 2009

Original :

The word “hallucination” conjures images of schizophrenics and drug abusers. Hallucinations seem to be the domain of psychosis and psychedelic drugs. But in reality, hallucinations can be common and ordinary, defined as a “sensory perception without external stimulation of the relevant sensory organ” (1).  The “creepy crawly” feeling one gets on the skin is an example of such a perception, or rather misperception, caused by a misfiring or other minor error in the nervous system.

Seeing Dead People

In general, hallucinations occur slightly more often in males than females. They are most common in males between ages 25-30, while females peak around age 40-50. Aging increases hallucinations in both sexes (2). The increase in hallucinations with age might have to do with the deaths of loved ones. It is not unusual to see dead friends and relatives; these hallucinations are considered normal, perhaps part of the grieving process. Almost half of widows and widowers have hallucinations of their dead spouse, most commonly in the first 10 years of widowhood (3). The occurrence of these hallucinations is unrelated to social isolation or depression— they actually increase with length of marriage, the happiness of the relationship, and parenthood. They are even considered helpful accompaniments and a coping mechanism of widowhood.

Hallucination can cause an altered sense of reality, which may manifest itself as visual or auditory distortions.


Hallucinations are most commonly associated with schizophrenia. Individuals may hear voices, or in rare cases see objects, that are not really there and believe that they are completely real, as opposed to a widow’s awareness that the vision of her dead husband is just in her head. Hallucinations experienced by schizophrenics also tend to be derogatory and hostile in tone.

Auditory hallucinations in schizophrenic individuals occur when normal cognitive processes are disturbed, such as monitoring of “self-generated verbal material.” These hallucinations are not a result of epileptic episodes in the auditory cortex, just small neural disturbances in regular brain activity. As a result, the auditory input seems just as vivid as a real perception.

Magnetic resonance imaging (MRI) brain scans during episodes of hallucinations show that the right hemisphere is highly active. The right hemisphere is associated with emotions and connections among the set of perceptions brought in through the sensory organs. It is thought to “make sense” of the surroundings by interpreting multiple sensory inputs. It is thought that during an episode, the schizophrenic individual may be trying to interpret and process what is being said by the voice in his head. Since these hallucinations are hostile in nature, the individual may be trying to form an emotional response to the input he is receiving (4). As a result, schizophrenic individuals become paranoid about the people or objects in their lives that the voices tell them are harmful.

Another illness associated with hallucination is Parkinson’s disease. Parkinson’s is a degenerative disease of the brain that leads to loss of motor skills, caused by the death of dopamine-secreting nerve cells in the brain. A first sign of Parkinson’s is an involuntary tic-like tremor or reduced mobility of certain body parts. Sensory processing then becomes disturbed, especially in vision. One study showed that almost 40% of people with Parkinson’s experience hallucinations, mostly visual. These individuals have “presence” hallucinations, where they perceive somebody else in the room. Some patients experience passage hallucinations, where they think they see something in their peripheral vision, probably due to a misinterpretation of a very flimsy perception in an early part of the visual cognitive process. Patients usually see strangers or domestic animals such as dogs, neutral objects that draw no emotional response (5).

Select individuals with Parkinson’s have more vivid hallucinations, perhaps due to other causes. One woman saw her dead son saying, “take care of yourself.” Another man, who was also diagnosed with dementia, saw “small incorporeal devils with a blurred face and a changing size.” He once thought that they were hurting him during an episode of lumbar pain, but for the most part the devils were not frightening to the man. In general, hallucinations are more prevalent in Parkinson’s patients with a longer duration of the disease. Also, the dopaminergic drug therapy administered to Parkinson’s patients is strongly associated with hallucinations (6). Hallucinations can also be induced with recreational drugs, such as LSD, by increasing activity in the same dopamine pathway (7).

Another neurological disorder that can cause hallucinations is called Charles Bonnet’s syndrome, or CBS. Frequent in elderly, visually handicapped individuals, CBS leads to “complex visual hallucinations without delusions or loss of insightful cognition.” The individuals are psychologically normal and aware that their hallucinations are not real. In a study, CBS was present in 11% of a group of 300 visually handicapped patients, 72 years old on average. The hallucinations ranged from mundane objects like a bottle or hat to funny situations, such as “two miniature policemen guiding a midget villain to a tiny prison van.” Others saw ghosts, dragons, or angels. Real images might combine with the imaginary, such as a hallucinated person in a real chair. Like the hallucinations experienced by Parkinson’s patients, the hallucinations generally have nothing to do with the person’s life (8).

Most of the individuals with CBS involved in the study did not tell their doctor about their hallucinations for fear of being ignored or considered insane. One individual who did tell the doctor received a response: “You’d better not talk about such silly things.” They also do not tell loved ones, due to the same fears. When the wife of a man with CBS expressed her amazement at her husband’s episodes and asked why he never told her, he simply replied, “I didn’t want to upset you” (9).

Wakeful dreaming

There is a strong stigma against hallucinations, as they are considered severely abnormal and a marker of a major psychiatric disorder. Since our society also has a strong stigma against psychological illnesses, people may hide their hallucinations. However, hallucinations are not really that extraordinary. Mahowald, Woods, and Schenk propose that hallucinations are really just like dreams in a conscious, wakeful state. In a normal awake state, the brain ignores activity generated internally while attending to the external stimulation it perceives. In a hallucination, whether induced by drugs, sleeplessness, or sensory deprivation, the brain processes the internal activity that it normally ignores, creating a hallucinogenic episode. Mahowald, Woods, and Schenk label this “wakeful dreaming” (10).

A strong social stigma against hallucination causes many people to conceal them. But some scientists argue that hallucinations are a wakeful occurence of the brain’s dream imagery.

Our body is covered with sensory organs that transmit information to the thalamus, part of the cerebrum, which is the part of the brain that controls many functions including sensory processing. The thalamus has two modes to control whether information goes to the forebrain (relay) or stops in the thalamus (oscillatory), controlling the input of environmental information into the cortex. The thalamus is in relay mode in wakefulness and REM (rapid eye movement) sleep, the sleep stage when vivid dreams tend to occur. The rest of the time, in non-REM (NREM) sleep, the thalamus is in oscillatory mode and the cortex is deprived of all environmental sensory information (11).

According to J. Allen Hobson, a revolutionary in dream research, dreams have five common features: hallucinatory imagery, bizarre cognitive features like discontinuity and incongruity, strong emotion, uncritical acceptance, and memory deficits (most dreams are forgotten) (12). These features would be considered very abnormal in a wakeful state. One explanation for hallucinations is based on Louis West’s theory of perceptual release. According to this theory, our life history and experiences create permanent neural changes that reprise themselves as memories, thoughts, and fantasies. Using these changes and the constant sensory input received from both the environment and inside the body, the midbrain gives rise to consciousness (13). With normal environmental sensory input, the midbrain organizes and limits the brain from reintroducing memory traces within itself. When the brain is deprived of sensory input (such as by blindness), brain circuitry encoding the memory of previous perceptions is released, causing the memories to be re-experienced as hallucinations (10).

Don’t try this at home

Hallucinations do not occur naturally in healthy people without psychological disorders. Extreme physiological stress can induce hallucinations, such as heatstroke or fasting. Religious or spiritual people use this form of physical exertion to experience “awakenings” and supernatural visions that can allow them to leave the normal realm of human perception.

In addition to recreational drugs, some prescription medication for disorders like ADHD can cause hallucinations, though only in small numbers. In one study, psychosis-mania events occurred in 11 out of 748 individuals treated with drugs. Children commonly had visual or tactile sensations of insects, snakes, or worms, described as a “creepy crawly” feeling (14).

Another interesting way hallucinations can arise is through intentional sensory deprivation. One study showed that healthy, normal sighted people who were blindfolded for several days started having visual hallucinations. Thirteen subjects wore blindfolds for five consecutive days. Ten people had visual hallucinations ranging from bright spots of light to complex hallucinations like faces, landscapes, and ornate objects. They started occurring on the second day of blindfolding and the subjects were aware that their hallucinations were not real (15).

For the most part, hallucinations are harmless and no real cause for worry, unless the person starts to believe that they are real. In that case, the person may need to seek medical treatment, though ironically, the person would not recognize that he needs help. Even in psychologically normal people like those with Charles Bonnet’s syndrome, hallucinations can be unwanted annoyances that cause emotional distress. But they can be healing or reassuring in some way to the person experiencing a hallucination. Martin Luther King reportedly heard God reassuring him during hard times in the form of an inner voice, saying, “Lo, I will be with you” (16). Hallucinations occur in many situations in different ways. They range from adverse symptoms of severe mental illness, to occasional, harmless dream-like events. Perhaps hallucinations are just one indication of our physical or psychological state of being.


1. American Psychiatric Association, Diagnostic and statistical manual of mental disorders (American Psychiatric Association, Washington, D.C., ed. 3, 1987), pp. 398.
2. A. Y. Tien, Soc. Psych. Psych. Epid. 26, 287-292 (1991).
3. W. D. Rees, Br. Med. J. 4, 37-41 (1971).
4. S. S. Shergill, M. J. Brammer, S. C. R. Williams, R. M. Murray, P. K. McGuire, Arch. Gen. Psychiatry 57, 1033-1038 (2000).
5. G. Fenelon, F. Mahieux, R. Huon, M. Ziegler, Brain 123, 733-745 (2000).
6. C. G. Goetz, C. M. Tanner, H. L. Klawans, Am. J. Psychiatry 139, 494-49 (1982).
7. P. Seeman. Synapse 1, 133-152 (2009).
8. R. J. Teunisse, J. R. M. Cruysberg, W. H. L. Hoefnagels, A. L. M. Verbeek, F. G. Zitman, Lancelet 347, 794-797 (1996).
9. M. W. Mahowald, S. R. Woods, C. H. Schenk, Dreaming 8, 89-102 (1998).
10. J. A. Hobson, R. Stickgold, Conscious Cogn. 3, 1-15 (1994). [as quoted in Teunisse 1996]
11. J. Monahan, H. J. Steadman, Violence and Mental Disorder: Developments in Risk Assessment (University of Chicago Press, Chicago, 1996)
12. A. D. Mosholder, K. Gelperin, T. A. Hammad, K. Phelan, R. Johann-Liang, Pediatrics 123, 611-616 (2009).
13. L. B. Merabet, D. Maguire, A. Warde, K. Alterescu, R. Stickgold, A. Pascual-Leone, J. Neuro-Ophthal. 24, 109-113 (2004).
14. B. J. Scott, J. Relig. Health 36, 53-64 (1997).

Beliefs Versus Knowledge: A Necessary Distinction for Explaining, Predicting, and Assessing Conceptual Change

Research Item –

Abstract – Empirical research and theoretical treatments of conceptual change have paid little attention to the distinction between knowledge and belief. The distinction implies that conceptual change involves both knowledge acquisition and belief revision, and highlights the need to consider the reasons that beliefs are held. We argue that the effects of prior beliefs on conceptual learning depends upon whether a given belief is held for its coherence with a network of supporting knowledge, or held for the affective goals that it serves. We also contend that the nature of prior beliefs will determine the relationship between the knowledge acquisition and the belief revision stages of the conceptual change process. Preliminary data suggests that prior beliefs vary in whether they are held for knowledge or affect-based reasons, and that this variability may predict whether a change in knowledge will result in belief revision.

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