Are Delusions on a Continuum? The Case of Religious and Delusional Beliefs (original) (raw)

Are delusions on a continuum? The case of religious and delusional beliefs

Dr. Emmanuelle Peters

Lecturer in Clinical Psychology
Institute of Psychiatry
London

In I. Clarke (Ed.) Psychosis and Spirituality; Exploring the New Frontier. 2001; Routledge.

“You’re trying to climb rain, Peter, or sweep sun off the pavement.”
(Retort from a psychotic man in conversation with Peter Chadwick, discussing his endeavours to investigate delusional thinking. Reported in Chadwick, 1992; p. xiv)

The concept of schizotypy

The view that there may be a thread of continuity between normality and psychosis is by no means a recent one, and the use of the concept of ‘schizoid personality’ was reported by Bleuler as early as 1911. Rado (1953) was the first to coin the term ‘schizotypal’, which he defined as the psychodynamic expression of the schizophrenic genotype. The concept of schizotypy was later elaborated by Meehl (1962) to denote the genetically determined disposition to schizophrenia. This led to the recognition of the so-called ‘borderline states’, to portray individuals who show abnormalities of personality phenomenologically similar to psychosis but which are too mild, or too transient, to justify being assigned to one of the major diagnostic categories. It is now becoming recognised that the existence of disorders which do not seem to fit conventional nosological categories is a more accurate reflection of the realities of psychological aberration: individuals do malfunction in ways that are not easily assimilated within our conceptions of psychiatric illness.

The continuity, or dimensionality, of psychotic characteristics is now firmly established amongst psychologists (Claridge, 1997), and, increasingly, amongst psychiatrists (van Os et al., 1999). Thus, psychotic symptoms are recognised as the severe expression of traits that are present in the general population, and which manifest themselves as psychological variations observable among individuals that range from the perfectly well-adjusted to those who, while showing signs of psychopathology, would not be considered clinically psychotic. Thus, the distinction between signs of mental illness (ie., symptoms) and the expression of human individuality (ie., traits) becomes blurred. One major hurdle to the acceptance of dimensional models had been the apparent incompatibility between accepting the view of schizophrenia as a disease and regarding psychosis as continuous with psychological health. Indeed, psychotic symptoms represent, for the most part, such extraordinary

disturbances of the mind that they may only be readily understood as serious malfunctioning of the brain. However, Claridge (1972; later revised in 1987), proposed a model of schizophrenia/schizotypy that incorporates both the view of schizophrenia as illness and as a psychological dimension (see Chapter 7, this volume).

The notion of continuity in mental illness has since been interpreted in differing ways. Claridge (1994) labels the two viewpoints as ‘quasi’ and ‘fully’ dimensional. The former takes the abnormal state as its reference point, and construes the continuity as varying degrees of expression of the clinical signs and symptoms. In contrast, the latter view emphasises dimensionality at the dispositional level, conceptualising schizotypy as a personality trait - albeit deviant - analogous to other individual differences, such as the extroversion-introversion dimension (Eysenck, 1992). A crucial difference is the notion that ‘deviant’ traits are seen in the fully dimensional model as being represented in personality as healthy diversity, while the quasi-dimensional viewpoint conceptualises schizotypy as attenuated psychotic symptoms.

The presence of schizotypal traits in the normal population can now be measured psychometrically from both the ‘fully’ (Claridge & Broks, 1984; Raine, 1991), and ‘quasi’ (Chapman et al., 1978; Peters et al., 1999b) dimensional viewpoints. Individuals scoring highly on such indices have been shown to resemble schizophrenics on a number of experimental correlates (Peters et al., 1994; Linney et al., 1998), which provides some evidence for the validity of the concept. In addition, the structure of schizotypy has been found to parallel the multidimensionality of schizophrenia, with three schizotypal dimensions being identified which are comparable to Liddle’s (1987) three-factor model of schizophrenia: a positive, a negative, and a disorganisation factor (Bentall et al., 1989; Claridge et al., 1996).

Much of the work on schizotypy has been concerned with positive symptomatology. For instance, it has been found that certain identifiable groups of people have elevated scores on positive symptom measures, such as those who believe in the paranormal (Thalbourne, 1994); those who have out-ofbody experiences (McCreery & Claridge, 1995); members of certain "cults"1 or New Religious Movements (NRMs) (Day & Peters, 1999); and those who have profound religious experiences (Jackson, 1997). Others have taken actual positive symptoms as their starting point, and investigated their incidence in non-psychiatric, or “normal” populations. Romme & Escher (1989), in their influential book “Accepting Voices”, were some of the first authors to point out that many individuals have auditory hallucinations outside the context of a psychiatric illness, which can be construed as beneficial life experiences, rather than as symptoms of an illness.

More recent, large-scale population surveys have confirmed the high incidence of seemingly benign positive symptoms in the general population. At least two studies have found that 10−15%10-15 \% of the normal population has had some kind of hallucinatory experience in their lives (Tien, 1991; Poulton et al., 2000), while approximately 20% report delusions (Poulton et al., 2000). In all, approximately one in four of the Dunedin Study cohort (approximately 1,000 people) reported having had at least one delusional or hallucinatory experience that was unrelated to drug use or physical illness (Poulton et al., 2000). Similarly, van Os et al. (2000) found that 17.5% of the Netherlands Mental Health Survey and Incidence Study (NEMESIS) sample (over 7,000 people) were rated on at least one symptom of psychosis using the Composite International Diagnostic Interview (CIDI; World Health Organisation; 1990), while only 0.4%0.4 \% qualified for a formal diagnosis of psychosis. This suggests that psychoticlike phenomenology is 50 times more prevalent than the narrower, medical concept of schizophrenia. In addition, strong associations existed between all types of symptom ratings on the CIDI and all

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  1. 1{ }^{1} The word “cult”, as it is used by the media and in popular parlance, tends to be a pejorative term for religious (or “pseudo-religious”) groups (Richardson, 1993a). The term commonly used by sociologists of religions is “new religious movement” (or NRM; Barker, 1996), and will therefore be the term used in this chapter. ↩︎

types of lifetime diagnoses, further suggesting that the boundaries of the “psychosis phenotype” do not concur with traditional diagnostic labels.

Psychiatric definitions of delusions

Delusions are of particular interest since they are, in some respects, the sine qua non of psychosis, and were described by Jaspers as “the basic characteristic of madness” (Jaspers, 1913). Despite the fact that they are easily identifiable in the clinic (Wing et al., 1974), and are widely acknowledged across diverse cultural norms as genuine symptoms of a variety of “illnesses”, they have resisted a century’s worth of attempts at definitions (Garety, 1985).

Jaspers (1913) originally ascribed three basic characteristics to delusions:

These three themes are still reflected in modern psychiatric definitions of delusions, such as in the Diagnostic and Statistical Manual of Mental Disorders-IV (DSM-IV; 1994):
“A false belief based on incorrect inference about external reality (falsity) that is firmly sustained (certainty) despite what almost everyone else believes and despite what constitutes incontrovertible proof or evidence to the contrary (incorrigibility). The belief is not one ordinarily accepted by other members of the person’s culture or subculture.” (my additions in italics)

This definition poses several problems, ranging from plainly false assumptions to points of vagueness and ambiguity, as well as unjustified theoretical conjectures. First, many delusions do not show

absolute conviction, and often conviction in the same belief will wax and wane over time (BrettJones et al., 1987, Sharp et al., 1996). Second, it has been demonstrated that delusions are not necessarily impervious to experience, and deluded individuals vary on how much they accommodate new evidence into their existing delusions (Brett-Jones et al., 1987).There is also now ample evidence that delusions are open to modification through cognitive-behavioural techniques (Chadwick & Lowe, 1994; Drury et al., 1996; Kuipers et al., 1997; Sensky et al., 2000; see also Kingdon, this volume???).

Both Brockington (1991) and Bentall et al. (1994) have made the important point that delusions need to be understood against a background of thorough knowledge of the psychology of “beliefs”. There is in fact a large body of work demonstrating the irrationality of so-called normal individuals (Sutherland, 1992). Holding a delusion with absolute conviction is not pathological in itself, since all beliefs which are personally significant or which support self-esteem tend to be held with absolute conviction, such as religious or scientific beliefs (Maher, 1988). Models of normal belief formation and maintenance (Alloy & Tabachnick, 1984) suggest that strong beliefs are typically maintained with little evidential support, and that our existing beliefs influence the process by which we seek out, store, and interpret relevant information. This well known “confirmation bias” allows us to be impervious to contradictory evidence, and only notice information which confirms our pre-existing beliefs (and of course science is notoriously guilty of this bias!). Therefore the certainty and incorrigibility traditionally ascribed to delusional beliefs are in fact the normal characteristics of any challenged belief that supports self-esteem.

Perhaps the most problematic statement in the DSM-IV definition is that delusions are “false beliefs”. First, in some cases the claims of the deluded patient cannot actually be proved as false. The best examples are the paranoid delusions, where individuals report being followed or spied on by such organisations as the CIA or the IRA. While many such reports are most unlikely to be true, Mayerhoff et al. (1991) describe a particular case where a young woman’s bizarre paranoid delusional system was later verified by tape-recorded telephone conversations. Fulford (1991) also points out that the

so-called “Othello syndrome” is known to reflect true infidelity in 1 in 10 diagnoses. Interestingly, van Os et al. (2000) report that 4%4 \% of the NEMESIS sample qualified for their category of “symptom present but with plausible explanation”. Strauss (1969) also demonstrated that psychiatrists were frequently forced to score the presence of a delusion as “uncertain” because of the apparent presence of external reality factors.

Second, in many cases the criteria of truth and falsity is just not applicable. Spitzer (1990) argues that one cannot attribute the notion of falsity to statements describing the contents of one’s own mental state or mentality (ie., “my mind from my own point of view”), since there is no evidence stronger than the evidence of experiencing a thought or sensation. The inherent “truthfulness” of one’s own mental activity, however distorted from reality, is demonstrated by scanning studies. For instance, Spence et al. (1997) showed that passivity experiences (the belief that one’s thoughts or actions are those of external or alien entities) are accompanied by hyperactivation of areas of the brain subserving attention to internal and external bodily space, while Woodruff et al. (1997) found that hallucinations are accompanied by activation of the brain areas which normally process external speech. These studies confirm that the experiences themselves are not false, since they are actually identifiable at a brain level. Rather, it is the unjustified claim that these experiences have some sort of intersubjective validity, and are not recognised as only lying within the scope of one’s mentality, which makes a belief delusional. Fulford (1991) also comments that in many cases it is the evaluative rather than the factual component of delusional thinking which is pathological.

Third, even if one could demonstrate that some beliefs were “false” or irrational, holding false beliefs is still a common occurrence. In fact, delusional themes commonly reflect beliefs held in the normal population and are not culturally atypical. They tend to keep pace with advancing technology and discoveries in the natural sciences, and tend to vary with social background, confirming that they are derived from acquired knowledge (Roberts, 1992). In addition, Bentall et al. (1994) point out that many common delusional beliefs, such as paranoid and grandiose delusions, reflect the person’s

position in the social universe, after all a common preoccupation. Similarly, delusions of reference are often concerned with the relationship between the self and the media (such as getting special, personal messages from the TV and radio), which is actively encouraged by our culture to be seen as a personally referential one. Indeed, many modern ads simulate situations where radio or TV presenters deliver private messages to one particular listener or viewer, while many magazine articles are written with the specific aim of creating the illusion of an intimate and private communication.

A frequently quoted American poll (Gallup & Newport, 1991) identified that 1/41 / 4 of the surveyed sample believed in ghosts; 1/41 / 4 believed they had had a telepathic experience; 1/61 / 6 believed they had been in touch with someone who had died; 1/101 / 10 had seen or been in presence of a ghost; over 50%50 \% believed in the devil; 1/101 / 10 had talked to the devil; and 1/71 / 7 had seen a flying saucer. As the editor of this volume notes in her introduction, Western culture is fascinated with “unexplained” phenomena such as UFOs, the paranormal, and conspiracy theories, and it is commonly accepted that the boundaries between science fiction and “rational” science are blurred. It is in fact doctors’ and scientists’ beliefs that are not representative of the general population, especially with regards to religious beliefs (Fenwick, 1996); and, of course, many delusions reflect a religious or spiritual theme. The psychiatric profession and its diagnostic tools have been attacked by some authors as medicalising and pathologising participation in certain types of religious groups and experiences (Richardson, 1993b) 2{ }^{2}. How does one distinguish between a belief in an “accepted” God (by the main

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  1. 2{ }^{2} An interesting example of the pathologising of spirituality by diagnostic categories (not specifically related to delusions) can be found in the description of “poverty of content of speech” in DSM-III-R (1987). The example given is as follows: Interviewer: “Okay. Why is it, do you think, that people believe in God?” Patient: “Well, first of all because, He is the person that, is their personal savior. He walks with me and talks with me. And uh, the understanding that I have, a lot of peoples, they don’t really know their own personal self. Because they ain’t, they all, just don’t know their own personal self. They don’t, know that He uh, seemed like to me, a lot of 'em don’t understand that He walks and talks with them. And uh, show 'em their way to go. I understand also that, every man and every lady, is just not pointed in the same direction. Some are pointed different. They go in their different ways. The way that Jesus Christ wanted 'em to go. Myself, I am pointed in the ways of uh, knowing right from wrong, and doing it. I can’t do any more, or not less than that.” (pp. 403-404).
    While readers will judge for themselves whether this speech sample “is adequate in amount but conveys little information”, R.D. Laing is reputed to have commented “if only I had had the ability to say that, I would have been saved” (David, personal communication). ↩︎

cultural standard of a particular society), an “unusual” God (as adhered to by subcultures within a particular society), and an “idiosyncratic” God (a delusion with a religious content)? Furthermore, how is the mental health professional qualified to make such a distinction?

Psychological conceptualisations of delusions

The discussion above illustrates the difficulties inherent in defining delusions, despite the fact that they are readily identifiable clinically. Newer psychological definitions have tended to concentrate on more descriptive, operational criteria (eg., Kendler et al., 1983; Oltmanns, 1988). Garety & Hemsley (1994), in an influential book, describe delusions as (i) continuous rather than dichotomous; (ii) multidimensional rather than unidimensional; (iii) potentially responsive rather than fixed; (iv) psychologically understandable; and (v) involving rational processes. Perhaps the most important recognition in these psychological definitions is the emphasis on delusions being neither dichotomous nor unidimensional. While the dichotomous view of delusions had been challenged by Strauss as early as 1969, and by Chapman & Chapman in the early eighties (1980), the lack of working definitions had hampered scientific research in this area. However, there is now a growing body of studies that support these claims empirically.

For instance, Gladis et al. (1994) found it difficult to classify “unusual beliefs” in a sample of relatives of schizophrenic probands as either odd beliefs or full delusions, as either transient or persistent delusions, and as either bizarre or non-bizarre delusions. Mojtabai & Nicholson (1995) also report that even in the case of bizarre delusions, which would be expected to be amongst the most clear-cut, the interrater reliability in a sample of 50 psychiatrists was less than satisfactory.

Similar conclusions emerge from surveys investigating delusional ideation in the general population. Verdoux et al. (1998) found that the range of individual item endorsement on the Peters et al. Delusions Inventory (PDI; Peters et al., 1996), in individuals with no psychiatric history, varied

between 5 and 70%70 \%, while Peters et al. (1999b) found that 10%10 \% of their normal sample had scores on the PDI which exceeded the mean of a psychotic, in-patient group.

The percentage of people reporting psychotic symptomatology is even higher in psychiatric, but nonpsychotic, populations. For instance, Altman et al. (1997) report that in a small, non-psychotic sample of adolescents from an American residential program, 24%24 \% reported having experienced delusional ideas, while Verdoux et al. (1999) found that most of their items exploring delusional beliefs were endorsed more frequently by depressed than non-depressed individuals. Many authors have also commented on the similarities between over-valued ideas, obsessions and delusions (Kozac & Foa, 1994).

These findings demonstrate fairly conclusively that there are no clear-cut divisions between normality and delusional thinking, and between delusions and other types of pathological thinking. There is also persuasive evidence for the multidimensionality of delusions, although researchers have disagreed over the exact number of relevant dimensions (Harrow et al., 1988; Kendler et al., 1983; Garety & Hemsley, 1987). However, throughout these studies the recurrent dimensions that emerge concern levels of conviction, preoccupation, and distress. Their importance were confirmed by Peters et al. (1999) who found that their normal and deluded samples were differentiated by their scores on the dimensions of conviction, preoccupation and distress, despite an overlap in the range of scores between the two groups in the endorsement of delusional items. Other recurrent themes concern the lack of interrelations between the various aspects of delusional experience (Kendler, 1983; BrettJones et al., 1987; Oulis et al., 1996) as well as the lack of covariance and a marked desynchrony of change among different measures over time (Brett-Jones et al., 1987; Chadwick & Lowe, 1994; Sharp et al., 1996).

The themes of continuity and multidimensionality are of fundamental importance in the literature comparing intense spiritual and religious beliefs with delusions with a religious content. Jackson (1997) attempted to distinguish between psychotic and spiritual phenomena by comparing two groups of individuals reporting such experiences on a variety of psychometric tools. He concluded that there was no clear borderline between the two, with a common, schizotypal personality trait underlying both forms on the spiritual-psychotic continuum. Jones & Watson (1997), on the other hand, found that schizophrenic delusions could be differentiated from religious beliefs held by “normals” on a number of significant variables, such as preoccupation, speed of formation, perceptual evidence and use of imagination. Such apparent inconsistencies are mostly owing to the types of people under study: whilst Jackson’s respondents consisted of individuals who reported unusual spiritual experiences, Jones & Watson’s sample deliberately excluded members of religious minority groups. Nevertheless, it should be noted that fewer differences were found between religious and delusional beliefs, than between delusional and control beliefs in the same individuals. Notably, religious and psychotic beliefs were not rated differently in terms of “truthfulness” or conviction.

Another interesting group to investigate are members of NRMs (see Richardson, 1995, for a review). The groups which have been most studied include the Jesus Movement Group (now disbanded), the Rajneeshees, and Hare Krishna devotees. Extensive data on their personal background and attitudes have been collected (Latkin et al., 1987; Richardson et al., 1979), as well as comprehensive batteries of personality assessments such as the Myers-Briggs Inventory and the Minnesota Multiphasic Personality Inventory (Poling & Kenny, 1986; Ross, 1983). Various measures of subjective wellbeing such as perceived stress, social support and self-esteem have been reported (Latkin et al., 1987), as well as several aspects of mental health such as depression, anxiety, loss of behavioural/emotional control and life satisfaction (Weiss, 1987; Weiss & Comprey, 1987). The overwhelming conclusions from this extensive body of work are that, on the whole, members of NRMs display group scores indistinguishable from those of normative samples, and are not, as a group, psychopathological, despite their idiosyncratic choice of deity and lifestyle (Richardson, 1995).

Day & Peters (1999) looked specifically at the schizotypal personality traits of individuals belonging to two NRMs, namely Druids 3{ }^{3} and Hare Krishna 4{ }^{4} devotees. They found that the NRMs scored higher than both Christian and non-religious control groups on questionnaires measuring positive, but not other types of symptomatology. Peters and her colleagues (Peters et al., 1999a) went on to investigate the level of delusional ideation in the same samples, also comparing them to a psychiatric in-patient, deluded group. The multidimensionality of delusions was also investigated by measuring levels of conviction, preoccupation and distress associated with such beliefs.

As predicted, it was found that the NRMs group endorsed significantly more items than the two control groups on both questionnaires used (PDI; Peters et al., 1996; Delusions Symptom-State Inventory (DSSI); Foulds & Bedford, 1975), and scored higher on levels of conviction. No differences were found between the NRMs and the control groups on levels of distress, supporting previous findings that individuals in NRMs are no more distressed psychologically than normative samples (Richardson, 1995). No differences were found between the Christians and the non-religious on any of the delusions measures, suggesting that being religious per se does not account for the NRMs members’ scores.

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  1. 3{ }^{3} Druidry is one of the major Pagan orders, whose ideas are inspired from Celtic traditions of a spirituality rooted in a love of nature. Druids have meetings, called Groves, usually fortnightly. Their beliefs explore sacred mythology, divination and other esoteric teachings. The Druids design and perform magical and religious ceremonies to change themselves and the world. This includes worshipping Old Gods and Goddesses, rites of passage (hand-fasting, child blessings, etc.), and observing eight seasonal festivals during the year (the solstices, equinoxes, and the four fire festivals).
    4{ }^{4} The Hare Krishna members studied live communally in a temple, and are free to worship at any time during the day. Although Krishna devotees trace their origins back through the sixteenth-century monk, Chaitanya Mahaprabhu, ISKCON (the International Society for Krishna Consciousness) was not founded until 1965 when His Divine Grace A. C. Bhaktivedanta Swami Prabhupada went to the United States. The movement’s philosophy promotes human well-being and the consciousness of God, based on the ancient Vedic texts of India. Its members wear saffron robes, and chant the Maha Mantra around town centres. The Krishnas are vegetarian, do not use intoxicants, do not gamble, and are celibate apart from procreation within marriage. ↩︎

Interestingly, the NRMs group could not be differentiated from the deluded group on their total scores on the PDI. Furthermore, they showed identical levels of conviction about the items they endorsed, indicating that they were as persuaded of the veracity of their experiences as the deluded in-patients. However, individuals from the NRMs were significantly less distressed and preoccupied by these experiences than their deluded counterparts. This is consistent with Jones & Watson (1997), who found that one of the distinguishing factors between religious and delusional beliefs was preoccupation, but not conviction or “truthfulness”. The NRMs members also scored significantly lower on the DSSI, which contains items of a considerably more florid nature than the PDI, confirming that they are not floridly psychotic. They also obtained significantly lower scores on Social Desirability, establishing that any differences between the two groups could not be explained by the NRMs members under-reporting their experiences to appear more socially desirable.

Such results support the notion that there is a continuity of function between normality and psychosis, with “normal” individuals (both non-religious and religious) being at one end of the continuum, the deluded individuals at the other extreme, and members of NRMs at the intersection 5{ }^{5}. Indeed, even this classification is over-simplified, since there was a considerable overlapping of the range of scores between the four groups, replicating Peters et al. (1999b) who found identical ranges on the PDI between a normal and deluded group. Secondly, these data confirm the multidimensionality of delusional beliefs, since the NRMs and the deluded groups could be differentiated by their scores on

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  1. 5{ }^{5} It should be pointed out that concluding that members of NRMs are at the intersection of the continuum from normality to psychosis is not another attempt to pathologise such individuals or their religious beliefs. The content and form of the NRMs participants’ religious experiences were not measured in the present study; indeed, since Druids and Hare Krishnas hold very different beliefs regarding their deity, they could not have been grouped together had the purpose of this study been to link actual religious beliefs with pathology. Rather, these groups were chosen because of their divergence from mainstream ideology, which somewhat parallels the departure of delusional beliefs from the accepted “norm”, but also because they are not displaying other signs of pathology (Richardson, 1995), remaining functioning members of society, unlike sufferers of psychosis. Indeed, members of NRMs would appear to qualify for the “happy schizotype” label coined by McCreery & Claridge (1995), who have emphasised that schizotypy is not a “malignant” personality trait per se, but may in fact be beneficial to the experient. This is similar to the case studies reported by Jackson & Fulford (1997), whose “anomalous” (anomalous in terms of our existing diagnostic criteria) experiences had adaptive and life-enhancing consequences. ↩︎

the distress and preoccupation dimensions, but not on the conviction dimension. Again this concurs with Peters et al. (1999b) who found that their deluded and normal groups were more usefully differentiated by their scores on such dimensions than on the number of items endorsed. Overall, these findings suggest that form may be more important diagnostically than content: it is not what you believe, it is how you believe it.

What differentiates religious and delusional experiences?

Empirical studies comparing religious and deluded individuals call into question our existing diagnostic criteria for delusions, which emphasise unduly the content or “bizarreness” of beliefs to classify them as pathological. Anthropological writings have long recognised that similar mental and behavioural states may be classified as psychiatric disorders in some cultural settings, and religious experiences in others (Bhugra, 1996). Some typical examples include glossolalia (speaking in tongues), common in Pentecostal (or “charismatic”) Christianity (Grady & Loewenthal, 1997), or possession phenomena such as the belief in possession by Zar spirits common in Africa (Grisaru et al., 1997; also see Toberts, Chapter 4, this volume). Indeed, some “psychotic” experiences (by Western standards) are actually highly revered in other cultures, such as shamanism (Prince, 1992). In fact, some authors have attempted (daringly) to explain the evolutionary paradox of schizophrenia by the idea that psychotic people may have, in previous Western, as well as other contemporary, cultures, been esteemed for their mystical experiences and enjoyed privileged social status as shamans, prophets, visionaries or saints (Jarvik & Chadwick, 1973). Price & Stevens (1999) have even postulated that, in some ways, the psychotic person is behaving like a prophet lacking followers.

As the editor notes in her introduction, altered states of consciousness, some of which bear close similarity to florid psychotic experiences, have actually been sought after by most societies since time immemorial. She points out that some religious practices and rituals can provide a controlled environment within which individuals can attain such altered states. Some religious rituals in fact

involve the use of hallucinogenics or other potent drugs to enable individuals to reach an alteration of consciousness, required to achieve closeness with their deity, such as the Yanomani tribe in the Venezuelan rainforests who ingest daily hallucinogenics to potentiate communication with their spirits. Many such examples are described by Toberts (Chapter 4, in this volume). Interestingly, the marginalisation of such experiences in contemporary Western Christianity has been paralleled by a proliferation of alternative subcultures, some spiritual, such as NRMs, and some secular, such as the widespread drug culture. The existence of such sub-cultures, and their pursuit of altered reality experiences, would suggest that we have an almost evolutionary need to “get out of our minds”, be that to fulfil a spiritual or purely hedonistic function.

Several authors have attempted to account for both the resemblance and differences between culturally idiosyncratic psychotic states, culturally validated mystical states, and drug-induced states (Saver & Rabin, 1997; Greenberg et al., 1992; Jackson & Fulford, 1997). These authors suggest that the characteristics of the two types of phenomena bear many similarities, such as apparent delusions or radical change of belief, hallucinations (voices, visions), strange behaviour and social withdrawal. However, although the content or type of phenomena may not differ, as mentioned in other chapters in this volume, “abnormal” experiences tend to be sought after in spiritually- and drug-induced states, and there is a relatively smooth and controlled entry in and out of those states. In contrast, they tend to be unwanted in psychotic states, and to be out of the person’s control.

The above authors further point out that the major differences seem to lie, firstly, in the interpretation and meaning given to the experiences, and, secondly, in the emotional and behavioural consequences of such experiences. Usually spiritual experiences have adaptive and life-enhancing consequences, while in psychosis similar phenomena often lead to social and behavioural impoverishment (Fulford, 1989). Greenberg et al. (1992) came to similar conclusions in their comparison of mysticism and psychosis: hallucinations, and grandiose and paranoid delusions, did not distinguish the psychotic from the mystic, and a diagnosis of psychosis rested on other associated factors such as duration of

the state, ability to control entry into the state, and deterioration of habits. Lenz (1983) has also suggested that the only difference between a religious belief and delusion is the course of development that the belief takes them. Hope, faith and freedom are found in mystical experiences, while this is not the case in deluded individuals: “the mystic swims, the psychotic drowns” (Chadwick, 1992; p. 93).

Interestingly, this is not a fool-proof distinction, as indicated by a study by Roberts (1991): he found that a group of chronically deluded individuals had comparable scores to a sample of Anglican Ordinands on “meaning” and “purpose of life” questionnaires, coupled with low levels of depression and suicidal inclination, suggesting that objective judgments of functioning may not correspond to the subjective fulfilment experienced by individuals. Similarly, some psychotic patients regard their voices as benevolent (Chadwick & Birchwood, 1994), enjoy their company, and may even actively invoke them (Romme & Escher, 1989). Other patients will deliberately stop taking neuroleptic medication, or ingest cannabis or other drugs to induce a delusional atmosphere or restore their psychotic state, presumably because they feel it is preferable to their non-psychotic reality. In contrast, some of the intense spiritual experiences described by Jackson & Fulford’s (1997) sample were neither solicited nor controllable, and were initially very frightening for the experiments.

I have argued elsewhere (Peters et al., 1999a; 1999b) that whether or not one becomes overtly deluded is determined not just by the content of mental events, but also by the extent to which it is believed, how much it interferes with one’s life, and its emotional impact. It is likely that the analysis of these dimensions is more revealing than the content of belief alone for placing an individual on the continuum from health to psychopathology: What makes people cross the psychotic “threshold” is not necessarily the content but the consequences of their beliefs. Clinical experience also corroborates this suggestion: Some religious delusions may not necessarily be “deviant” in content (eg., they may adhere to mainstream Christian doctrine, and be based on the Bible), but rather it is the fact that the individual is entirely immersed in his/her religious preoccupation (eg., reading the Bible all day), and

the potential emotional and behavioural consequences of the beliefs (eg., extreme distress if the closeness to God temporarily wanes, or self-neglect or complete passivity in the face of God’s omnipotence), which make the belief pathological. Indeed, psychological interventions for delusional beliefs usually involve dissociating percepts from beliefs and emotional reactions, as well as exploring alternative coping or behavioural strategies, rather than directly challenging the content of delusions.

Which factors are responsible for the pathognomonic features of idiosyncratic beliefs?

The empirical studies reported in the previous section reflect both the relatedness and distinctiveness of psychotic and religious experiences. On the one hand, they must share some common psychological mechanism, which leads both groups to hold idiosyncratic ideas about the world and be subjected to unusual experiences. One possible candidate is the sharing of a schizotypal central nervous system or personality, as would be suggested by Jackson’s (1997) and Day & Peters’ (1999) results. Other possibilities may include cognitive style, such as difficulties in probability judgments and hypothesis-testing, which has been demonstrated in deluded subjects (Garety & Freeman, 1999), people who believe in the paranormal (Blackmore & Troscianko, 1985; Williams & Irwin, 1991), and people who score highly on the PDI (Linney et al., 1998). Of course, these hypotheses are not mutually exclusive, and may in fact be causally related.

On the other hand, there must be some differences that account for the divergence in the emotional and behavioural consequences of the two groups’ beliefs and experiences. It is unclear at this stage whether those differences are biological, psychological, or socio-cultural, or indeed a combination of the three. Jackson (Chapter 11, in this volume) proposes a “problem-solving” model to account for the benign effects of intense religious experiences, as opposed to the deterioration found in psychosis. He suggests that in both cases the experiences are encountered during personal crises and are accompanied by a high degree of emotional intensity. In the case of spiritual experiences there is a “negative feedback” mechanism in which the precipitating crisis is resolved by the religious insight, and leads to increased coping behaviour. In contrast, with psychosis there is a “positive feedback”

system where experiences lead to a higher state of arousal, which then precipitates increasingly florid experiences, even though a “delusional insight” may be achieved. Gumley et al. (1999) further suggest that once one episode of psychosis has been endured, meta-beliefs about the controllability and nature of “illness” and symptoms develop, which then determine the future course the psychosis takes. Individuals who believe they have no control over their illness are likely to respond to visuoperceptual changes or increased arousal by increased vigilance, anxiety, worry, sleeplessness and potentially withdrawal, in itself increasing the risk of relapse, thereby creating a similar “positive feedback” loop to that described by Jackson.

Whether a positive or negative feedback loop is triggered could again be determined by a variety of factors. First, it could be that the content of the experiences is more inherently frightening in psychosis: Jackson & Fulford (1997) note that although the spiritual experiences of their small sample could mostly all be classified as psychotic, nevertheless there was a conspicuous absence of common psychotic beliefs such as delusions of persecution. Interestingly, in a study charting the course and outcome of a group of 88 delusional patients, Jorgensen (1994) reported that patients with main delusions of persecution or influence had the most pessimistic outcome. It is possible that some types of delusions, such as persecutory beliefs, are more likely to engender a cyclical process whereby individuals provoke actual rejection and control by others by virtue of their behaviour, thereby providing confirmation of their beliefs and increased social isolation (Roberts, 1992).

An interesting insight into one potential distinguishing feature in the quality or type of experiences between mystical and psychotic states is provided by Chadwick (Chapter ? in this volume). While he puts forward a list of parallels between the two states, one of the fundamental difference seems to be that in the mystic the “intuitions” appear to emanate from the self towards the world, while in the psychotic the “intuitions” tend to revolve around the intents of the world towards the self. For instance, while the mystic notices that “there is great harmony and oneness between all things”, the psychotic notices that “people and the world are all together in communication against me”; while the

mystic is “in touch with everyone”, the psychotic believes that “everyone can hear my thoughts”; while the mystic is open to “reality being weird”, the psychotic believes “there’s something weird happening in the world directed at me”, and so forth. Thus, while in the mystic there is effort after meaning of where the self fits into the universe (from self to world), in the psychotic there is effort after meaning of events in relation to the self (from world to self).

Second, accompanying symptoms such as thought disorder and third person hallucinations were also absent in Jackson & Fulford’s spiritual sample, while they are common in psychosis. While this is likely to be due to biological factors, the psychological effect would be to reduce the coping resources of the individual, thus leaving him or her more vulnerable to a positive feedback system. In the study mentioned above, Jorgensen & Jensen (1994) do indeed find that subjective thought disorder is predictive of the persistence of delusional beliefs.

Third, the cognitive resources of the individual may play a part in determining whether s/s / he is able to make sense of the experiences. Indeed, there are numerous reports of the impoverishment of cognitive functioning in individuals with a diagnosis of schizophrenia (Russell et al., 1997). Interestingly, deficits are particularly marked in tasks requiring cognitive flexibility (Pantelis & Nelson, 1994), a cognitive process that has been identified as a predictor of good response to CBT for delusions (Garety et al., 1997). In other words, it may be that it is a lack of cognitive flexibility that prevents individuals from reframing their beliefs and experiences both at the initial stage and in response to therapeutic dialogue.

Lastly, support and validation within the socio-cultural context of the individual may help to alleviate stress. Again this is supported by Jorgensen & Jensen (1994), where the persistence of delusional beliefs was predicted by living alone and the experience of psychosocial stressors. One pertinent consideration is the potential buffering role of religious affiliations (such as membership of NRMs). Muffler et al. (1997), for instance, report that in the experimental zeitgeist of the 1960s and 1970s,

religious communal organisations assisted large number of young people who were, temporarily at least, “shaken loose” from their usual social locations. The religious groups typically shared a belief system built on the religious ideology of the group, and members supported each other in the acting out of the new beliefs and values. Behaviour deemed deviant and negatively sanctioned in previous reference groups would be accepted and encouraged in the new environment.

In addition to offering a protective role in terms of social and emotional support, NRMs may also help with the validation and normalisation of their beliefs and experiences. Thus, a religious interpretation of unusual experiences may help individuals achieve meaning, self-esteem and a sense of control which then increases coping behaviour (Crossley, 1995; Jackson & Fulford, 1997). Indeed, recent approaches to psychosis have been influenced by the Beckian model (Kovacs & Beck, 1978), which postulates that it is the way in which experiences are evaluated, rather than the fact that they occur, which determines their affective and behavioural sequelae (eg., Chadwick & Lowe, 1994; Garety & Hemsley, 1994). Therefore the additional role of religious affiliations would be to replace a catastrophic interpretation of the experiences themselves with a more benign evaluation; ie., as an authentic sign from God rather than as potential symptoms of mental illness. Indeed, Chadwick (this volume) notes how self-doubt was undoubtedly influential in mediating his switch from the mystical to the psychotic, and he has previously reported of his own psychotic experiences: “I had neither the intelligence nor the conceptual apparatus nor the spiritual development to handle the experience that was now going out of control” (Chadwick, 1992; p. 37; my italics). Prince (1992) also points out that cultures which invest meaning into, and provide institutional support for “unusual states”, can channel at least some of the experiments into socially valuable roles. This would suggest that NRMs are in fact beneficial to one’s mental health, in contrast to some of the psychiatric writings which have pathologised nonconformity in the religious sphere (see Post, 1992; Neeleman & Persaud, 1995; Crossley, 1995, for an analysis of the role of religious experience in psychiatry).

Research into schizotypy has shown that certain groups of people have similar experiences to the positive symptoms of schizophrenia while remaining functioning members of society. The specific case of delusions was in this chapter. A number of empirical studies that have endeavoured to distinguish between delusional and religious beliefs were examined. The overall findings from this body of empirical work provide support, firstly, for the notion of a continuum between normality and psychosis, and, secondly, for the necessity to consider the multidimensionality of delusional beliefs. It is argued that what makes people cross the psychotic “threshold” is not necessarily the content but the consequences of their beliefs: It is not what you believe, it is how you believe it.

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