A Questionnaire Survey
1986, Journal of Nervous and Mental Disease, 174, 615-619
Copyright © 1986 by The Williams & Wilkins Co.
SUSAN BLACKMORE, PH.D.
Brain and Perception Laboratory, The Medical School, University of Bristol, Bristol BS8 1TD, England.
I would like to thank Dr. 0. T. Phillipson and Dr. J. Harris for collecting the data, and the Perrott-Warrick Studentship in Psychical Research and the Society for Psychical Research for financial support.
Questionnaires on perceptual distortions, symptoms of schizophrenia, and out-of-body experiences (OBEs) were completed by 71 volunteers with a history of schizophrenia and 40 control subjects (patients in a hospital accident ward). Significantly more of the schizophrenics (42%) than of the control group (13%) answered “yes” to a question about OBEs. However, a follow-up questionnaire showed that only 14% of schizophrenics (i.e., the same as the control group) had had “typical” OBEs, in which a change of viewpoint was reported. Those reporting typical OBEs did not report more perceptual distortions or symptoms of schizophrenia than did those reporting no OBEs, although those reporting other atypical experiences did. On this basis there is no evidence to consider the typical OBE as pathological or as symptomatic of schizophrenia.
An out-of-body experience (OBE) is an experience in which a person seems to perceive the world from a location outside of the physical body. In other words the “self seems to leave the physical body. Sometimes, although not invariably, the experient reports looking down on the physical body and having a duplicate body of some sort (Blackmore, 1982; Green, 1968).
The OBE can occur under almost any circumstances (Blackmore, 1982; Green, 1968), but it is especially common during physical relaxation (such as before sleep), when the experient may suddenly seem to be hovering above his own body, or as part of the near – death experience (see Greyson and Flynn, 1984). Patients resuscitated from clinical death, or those who narrowly escape fatal injury in car crashes or mountaineering falls, often report being able to observe the events as though a spectator.
Such experiences have been claimed by up to 50% of selected groups (e.g., Tart 1971), and in random surveys about 10% to 20% of respondents claim to have had them (Blackmore, 1984; Palmer, 1979; for review, see Blackmore, 1982). Some people thoroughly enjoy their OBEs but others are frightened by them and sometimes assume that they are “going crazy.” It is therefore important to determine whether the OBE is a symptom of any pathology, whether it is associated with any recognized syndrome, and therefore whether its appearance should be considered pathological.
The experience has often been likened to autoscopy, depersonalization, derealization, and schizophrenic loss of body boundaries. However, it can be quite clearly distinguished from all of these.For example, Noyes and Kletti (1976) likened near death experiences to depersonalization. However, in both derealization and depersonalization the subject feels unreal or less real than usual. In OBEs it is typical for exponents to feel “more real” than ever before. They often describe their thinking as clear and lucid and their surroundings as realistic, as in this simple description by a woman who had frequent “projections”:
“I left my body as soon as I fell asleep…. My faculties were absolutely clear as I left the house, and travelled across London” (Blackmore, 1982, p. 21).
The experience may sound bizarre but there is no loss of reality.
Autoscopy was defined by Critchley (1950) as “delusional dislocation of the body image into the visual sphere” and by Lukianowicz (1958) as “a complex psychosensorial hallucinatory perception of one’s own body image projected into the external visual space”. Both these imply that the self remains associated with the physical body and that a duplicate body is seen at a distance. This is clearly not an OBE according to the definition given above. The distinction is confirmed by some cases given. For example, Lukianowicz (1958) describes a case of autoscopy in which an architect observed a complete duplicate of himself enter the room, merge with himself, and then depart again.
However, others have used the term less clearly. For example, Damas Mora et al. (1980) defined heautoscopy (the term they prefer to autoscopy) as “the experience of seeing one’s own body at a distance” and Lippman (1953) defines autoscopy as “hallucinations of physical duality.” These could clearly include OBEs. Indeed, Lippman gives an account of autoscopy in a woman suffering from migraine. Just before the onset of a headache she was serving breakfast. She says, “There would be my husband and children, just as usual, and in a flash … I felt as if I were standing on an inclined plane, looking down on them from a height o a few feet, watching myself serve breakfast” (p. 346). This clearly is an OBE as defined here.
I have argued (Blackmore, 1982) that it is useful to distinguish between the OBE and autoscopy. In the OBE the self seems to leave the physical body whereas in autoscopy the self remains with the physical body and a double is seen at a distance.
In schizophrenia, body boundary disturbances are common. Sufferers complain of fusion phenomena, underestimation or overestimation of the size of body parts, or total loss of parts of the body. Occasionally his may be confounded with sensations of being outside the body, as in an OBE. However, Gabbard and Twemlow (1984) have carefully distinguished the two phenomena. The main difference is that in schizophrenia reality testing is lost whereas in the typical OBE it is maintained. Also OBEs tend to be short lived: the identity remains intact, the location of the body is clear, and the experience may be integrated into the personality. By contrast, in schizophrenic disturbances there is chronic difficulty with the delineation of body boundaries and the identity is threatened.
Gabbard and Twemlow (1984) have also administered a variety of psychological tests to large numbers of people reporting OBEs and found that they tend to be unusually healthy and well adjusted, but of course OBEs are not restricted to the psychologically healthy.
The question now arises whether the OBE is a symptom of any pathology, in particular schizophrenia, or whether it should be treated as a perfectly normal occurrence. If the former is the case then we would expect schizophrenics to have an unusually high proportion of OBEs. If the latter is true we would expect no more OBEs among schizophrenics than among others. Additionally, if the OBE is a symptom of pathology then we would expect it to be associated with other symptoms. For example, those schizophrenics showing most severe symptoms of their illness would also be expected to have OBEs more often.
The study reported here addressed these two questions by means of a questionnaire survey.
The data were collected in conjunction with a study of perceptual distortions by Phillipson and Harris (1985). Some of the OBE data have been reported previously and comparisons have been made with a group of students (Blackmore and Harris, 1983). A more appropriate control group was used here.
The questionnaire consisted of a typed booklet containing questions about personal history, perceptual distortions, symptoms of schizophrenia, and OBEs.
The section on visual distortions explained that we were interested in “when real objects you are looking at appear in some way changed, or odd, or not as you would expect them to look.” Hallucinations and “tricks of the light” were specifically excluded. There were sections on seven types of distortions: distortions of color, movement, brightness or contrast, depth, shape, size, and tilt. The schizophrenics were asked about drug treatment received and whether it seemed to increase or reduce the frequency of visual distortions or OBEs.
The section on symptoms included questions of high diagnostic significance for schizophrenia. These were taken from the Present State Examination (9th ed.; Wing et al., 1972), and included questions on thought interference, hearing voices, and seeing visions. The OBE question was taken from Palmer (1979). It asked, “Have you ever had an experience in which you felt that ‘you’ were located ‘outside of or ‘away from’ your physical body; that is the feeling that your consciousness, mind or center of awareness was in a different place than your physical body?” Possible answers were “No,” “Yes, once,” “Yes, several times,” “Yes, often,” and “Yes, can experience it at will.”
The control subjects were asked for a description of the experience straight away. Based on these descriptions, all five of the OBEs reported could be categorized as “typical” OBEs. Among the schizophrenic group, those who answered “yes” to this question were later sent a follow-up questionnaire asking for more details and a description of their OBE(s).
John Harris and Oliver Philipson (Anatomy Department, University of Bristol) placed an advertisement in the Newsletter of the National Schizophrenia Fellowship asking for volunteers with a history of schizophrenia to give information about their experiences (unspecified experiences). No further information was given at this stage. A total of 71 completed questionnaires were received from this group. There were 30 women and 41 men, with a mean age of 36 years. All claimed previous diagnosis as schizophrenics and only three did not report at least one of the symptoms of schizophrenia included in the questionnaire.
The control group consisted of 40 patients admitted to the Accident and Emergency Wards of the Bristol Royal Infirmary. Patients with head injuries, those taking drugs other than painkillers, or those younger than 15 or older than 70 years of age were excluded. There were 14 women and 26 men, with an average age of 35 years. Of these subjects only three answered “Yes” to the questions about symptoms of schizophrenia. These questions therefore discriminated extremely well between the two groups.
The questionnaire was sent by mail to the schizophrenic group and given to the control group in the hospital to complete at their leisure. After the completed questionnaires were received from the schizophrenic group, a second questionnaire was sent to all those who claimed to have had OBEs. This questionnaire asked for further details about the experience in an attempt to categorize it more accurately and compare it with the OBEs reported elsewhere. This follow-up was not possible for the control group because they were not required to give their names and addresses. However, they were asked for a description of their OBE in their questionnaire.
The incidence of OBEs appeared superficially to be quite different in the two groups. Forty-two percent of the schizophrenic group but only 13% of the control group claimed to have had at least one OBE. The difference is significant (x2 = 10.5, df 1, p < .01).
However, when the 30 schizophrenics who claimed OBEs were sent a follow-up questionnaire asking for more details of the experience, it became obvious that not all those who answered “yes” had in fact had anything like a typical OBE. Of these 30, 22 returned the completed questionnaire with a description of the experience. The defining characteristic of an OBE is seeming to have a viewpoint outside of the physical body. Of these 22, only 9 gave descriptions that could be categorized as “typical” OBEs. Some examples are given below.
If the other 13 people were considered not to have had an OBE the proportion of schizophrenics who had had OBEs dropped to nine of 63 (excluding the eight who did not respond to the second questionnaire). This is 14%—almost exactly the same as in the control group.
As expected the schizophrenics reported more perceptual distortions and more symptoms of schizophrenia than did the control group (see Table 1) (see Phillipson and Harris  for more details).
The second question concerns whether having OBEs is associated with the three symptoms of schizophrenia included here, that is, seeing visions, hearing voices, and thought interference. All three symptoms were more common among the 30 who initially claimed OBEs, and the difference is significant in the case of seeing visions (x2 = 4.74, df 1, p < .05).
This might imply that the OBE is indeed more common in those more seriously ill. However, the data were broken down separately for those who reported no OBE, those who reported typical OBEs, and those who reported other experiences or “pseudo-OBEs” (see Table 2—eight subjects who claimed OBEs in the first questionnaire but did not return the second questionnaire are excluded). This analysis clearly shows that the effect is minimal for typical OBEs whereas it is large for pseudo-OBEs. In other words those subjects who report typical OBEs are no more likely to report the symptoms of schizophrenia than are those reporting no OBEs.
The same applies when we look at perceptual distortions. The 30 who initially claimed OBEs report on average more perceptual distortions (X 2.5) than others (X 1.2, t = 2.8 df 67, p < .01). However, when they are broken down into three groups as before, the difference is much smaller (see Table 2).
In the control group there is no significant difference in the number of perceptual distortions reported between those reporting OBEs and those reporting no OBEs (X A and .2, respectively). Symptoms of schizophrenia are too rare in the control group for any comparisons to be made.
Percentage of Schizophrenic and Control Subjects Reporting OBEs, Perceptual Distortions and Symptoms of Schizophrenia
|OBEs||Perceptual Distortions||Symptoms of Schizoprenia|
|Schizophrenics (N = 71)||14||63||94|
|Control Subjects (N = 40)||13||33||8|
Schizophrenic Group Only
Symptoms of Schizophrenia and Perceptual Distortions in Those Reporting OBEs and Others
|Visions||Thought Interference||Voices||Mean No of Distortions|
(N = 41)a
(N = 9)
(N = 13)
(aN varies slightly within groups because not all subjects answered all questions)
Finally, the schizophrenics were asked how the frequency of their OBEs was affected by the onset of their illness and by any drug treatment they received. In many cases they reported only one or “a few” OBEs and so such a comparison is not meaningful. Of the 30 who initially claimed OBEs, 18 claimed that their OBEs became more frequent with the onset of their illness, seven that they stayed the same (or they had too few to tell), and five that they became less frequent. Drug treatment was claimed to reduce OBEs. Three claimed that their OBEs became more frequent with drug treatment, 16 that there was no effect, and 11 that they became less frequent. The numbers here are too small to consider just typical OBEs. In any case these data must be treated with caution because it is very hard to estimate changes in frequency of infrequent events, especially retrospectively.
A lot of emphasis has been placed on the distinction between typical OBEs and other experiences initially claimed as OBEs. To give a clearer idea of the kinds of experience being reported, some examples follow.
Nine schizophrenics reported OBEs that can be classed as typical or true OBEs. For example, a 43-year-old woman who reported few distortions and suffered thought interference and visions, although she never heard voices, reported two OBEs that occurred after recovery from her illness:
“‘A’ occurred when I was in bed, resting but not asleep. The bedroom light was on. I found myself in the position where a rocking chair was situated near the foot of the bed. I could see my head on the pillow and the colors of the pillow case and counterpane, which were as usual. The experience did not last long and I had no difficulty getting back into my physical body.
‘B’ occurred about a week later. I was in bed…. I seemed to leave the house (I think through the window) and travel a great distance.”
She goes on to describe further “travels” during that OBE and adds that she was studying yoga at the time.
A 43-year-old man who reported no visual distortions but did suffer from thought interference and hearing voices described an experience which occurred:
“On stage in the middle of a play at Her Majesty’s Theatre, Barrow-in-Furness. It didn’t affect my performance in any way at all. I went on acting while my center of consciousness (I) floated about 15 feet above the scene I was in.”
Like so many others he feels he needs to add,
“I’m not making this up: it was a very exhilarating experience and an absolute mystery to me.”
A 31-year-old woman who reported no visual distortions, but did have hallucinations and thought interference and heard voices, reported two experiences. In the second:
“I was resting on my bed, when I suddenly seemed to withdraw from my body. ‘I’ was to the side of the bed, looking on my body, which looked purple and emaciated, and I just had a sure feeling that I was dead! The next thing I knew, I woke up, perfectly normal, and was back in my own body.”
This woman reported that antischizophrenic drugs reduced the occurrence of her OBEs. She also claimed that, after a subsequent OBE, “I have never felt afraid of death since.”
Contrasting with these are many diverse experiences that may or may not be comparable to OBEsbut were claimed as such. For example, a 31-year-old man who claimed to have few visual distortions but all three symptoms of schizophrenia explained:
“During my last schizophrenic breakdown I was transported, through music, to Titan (Saturn’s moon), on which the gods had erected a theatre in which the fate of the earth was to be determined. I travelled without a body—as an idea or thought or some intangible aspect of consciousness.”
I do not consider this an OBE because he does not mention any separation of physical body and self, nor does he describe leaving the body nor observing it from a distance. He nevertheless claimed that his OBEs increased with the onset of his illness and were reduced by the medication he took.
One 44-year-old man, whose only reported symptom was thought interference and who reported only distortions of size, described the following experience:
… about 20 years ago when I was about 21 and undergoing treatment in hospital…. I felt that my body had shrunk and that other people and objects around me had taken on increased proportions…. It was, however, rather unpleasant and frightening at the time.”
He claimed that this experience increased with the onset of his schizophrenia and was not affected by drug treatment.
Others described apparitions, deja vu experiences, lucid dreams, experiences of fusion with others, and body image disturbances of various kinds. None of these can be classed as typical OBEs, because none involves a change in viewpoint to a position outside the body.
Among the control group only five OBEs were reported and a follow-up questionnaire was not given. The descriptions were mostly simple and were clearly typical OBEs. For example, one 22-year-old woman reported feeling “as if I was floating but was looking down on myself”.
A 58-year-old man reported that he seemed to be “above and looking down on my body in bed” and an 18-year-old woman reported that her OBEs occurred “not that often—if I lie in bed and hold breath I can come out of myself and feel as if I’m floating”.
Superficially the results seem to show that the schizophrenics have far more OBEs than do control subjects and that those who have OBEs also suffer from more perceptual distortions and more of the symptoms of schizophrenia. However, when the OBEs are distinguished on the basis of the descriptions given, into typical OBEs, in which the person seems to leave the body, and pseudo-OBEs, which include all sorts of other experiences, then these differences disappear It seems that the schizophrenics do not have significantly more OBEs than do control subjects and that having OBEs is not related to either perceptual distortions or to the symptoms of schizophrenia This confirms a previous finding in which no relationship was found between having OBEs and perceptual distortions in a group of students (Blackmore and Harris, 1983).
Some problems remain concerning the selection of subjects. The subjects in the schizophrenic group were self-selected (although not for having OBEs, of course) and those in the control group were more nearly random Also the schizophrenics were asked about their OBEs on two separate occasions and the control group on only one. This might produce spurious between-group differences that have nothing to do with schizophrenia. The fact that the proportion of typical OBEs was the same in both groups might imply that any such effect was minimal. Nevertheless, further research without these problems is obviously warranted.
On the basis of the findings reported here, we may answer our original questions very simply. OBEs do not seem to be pathological. People who experience them may fear that they are “going crazy” but in fact normal control subjects experience just as many typical OBEs as schizophrenics do. Also, among schizophrenics, those who report more symptoms are no more likely to have typical OBEs. There seems to be no basis for considering the appearance of OBEs as an indication of pathology or as a symptom of schizophrenia.
Blackmore SJ (1982) Beyond the body. London: Heinemann
Blackmore SJ (1984) A postal survey of OBEs and other experiences. J Soc Psychical Res 52:225-244
Blackmore SJ, Harris J (1983) OBEs and perceptual distortions in schizophrenic patients and students. In WG Roll, J Beloff RA White (Eds), Research in parapsychology 1982 (pp 232-234). Metuchen, NJ: Scarecrow.
Critchley M (1950) The body image in neurology. Lancet 1:335-340
Damas Mora JMR, Jenner FA, Eacott SE (1980) On heautoscopy or the phenomenon of the double: Case presentation and review of the literature. Br J Med Psychol 53-75-83
Gabbard GO, Twemlow SW (1984) With the eyes of the mind. New York: Praeger
Green CE (1968) Out-of-the-body experiences. London: Hamish Hamilton
Greyson B, Flynn CP (Eds) (1984) The near-death experiences: Problems, prospects, perspectives.Springfield, IL: Thomas
Lippman CW (1953) Hallucinations of physical duality in migraine. J Nerv Ment Dis 117:345-350
Lukianowicz N (1958) Autoscopic phenomena. Arch Neurol Psychiatry 80:199-220
Noyes R, Kletti R (1976) Depersonalisation in the face of life threatening danger: A description. Psychiatry (Wash DC) 39:19-27
Palmer J (1979) A community mail survey of psychic experiences, J Am Soc Psychical Res 73:221-252
Phillipson OT, Harris J (1985) Perceptual changes in schizophrenia: A questionnaire survey. Psychol Med 15:859-866
Tart CT(1971) On being stoned: A psychological study of marijuana intoxication. Palo Alto, CA: Science and Behaviour
Wing JK, Cooper JE, Sartorius N (1972) The measurement and classification of psychiatric symptoms.Cambridge, UK: University Press