Orne, M.T. Undesirable effects of hypnosis: The determinants and management. International Journal of Clinical and Experimental Hypnosis, 1965, 13, 226-237.

The International Journal of Clinical and Experimental Hypnosis 1965, Vol. XIII, No.4, 226-237



Institute of the Pennsylvania Hospital and University of Pennsylvania

Abstract: Various kinds of complications arising from the use of hypnosis are reviewed. The distinction is drawn between the induction of hypnosis when it is perceived as an episodic event, as in a laboratory context, versus the effect when it is perceived as leading to permanent changes, as in a therapeutic context. An attempt is made to draw these and other distinctions in order to understand better the possible sources of difficulties.

Complications arising from the use of hypnosis have often been discussed, and belief in the dangers of the procedure is widespread. In evaluating these dangers, it is necessary to take account of the context in which hypnosis is employed. A therapeutic situation, in which both patient and therapist expect substantial and perhaps permanent changes of behavior and personality, is very different from the more episodic uses of hypnosis in research.

In therapy itself, the effect of the hypnotic induction per se must be distinguished from the effects of suggestions made during trance, and interpretations made afterwards. Some of the dangers of hypnotic therapy may have been exaggerated in the literature, but others are surely real, if only because they are present in nonhypnotic therapy also, and for the same reasons. Not only the reactions of the patient, but also those of the therapist, must be considered.

Hypnosis in a nontherapeutic context: laboratory research

Over the years, our laboratory has put several thousand "normal college students" through hypnotic induction procedures. These inductions take place in a setting which is clearly defined as "experimen-

Manuscript submitted September 24, 1963.

1 The research upon which this paper is based was supported in part by grant number AF-AFOSR-707-65 from the Air Force Office of Scientific Research, contract number Nonr 4731 (00) from the Office of Naval Research, and grant number MH 11028-01 from the National Institute of Mental Health. An earlier version of this paper was originally presented at the American Psychiatric Association, Toronto, May, 1962.

2 I would like to thank my colleagues at the Unit for Experimental Psychiatry, Julio M. Dittborn, Frederick J. Evans, Ulric Neisser, Donald N. O'Connell, Emily Carota Orne, and Ronald E. Shor, for their constructive comments and criticism during the preparation of this manuscript.




tal," rather than "therapeutic." Subjects are explicitly informed that no treatment of any kind will be undertaken. No subjects are used who have obvious psychopathology, or who seem to have volunteered for the experiment chiefly in the hope of self-improvement. A volunteer who requests help of any kind (for example, in the control of nail biting or smoking) is referred to his student health service and excluded from further experimental participation. The proportion of subjects discarded for such reasons has never exceeded five per cent. Thus the situation is defined explicitly as episodic (Garfinkel, in press): assurances are given that, at the completion of the experiment, the individual will be exactly as he was when he began. No permanent change, either positive or negative, may legitimately be expected.

Despite the large number of subjects tested under these conditions, virtually no serious negative reactions to hypnosis have arisen. We have never encountered the anxiety reactions, symptom formations, depressions, or decompensations which have been reported in other settings. Minor complications do appear: an occasional mild transient headache, drowsiness, transient nausea, or dizziness on awakening. These difficulties, if encountered at all, occur typically during the first induction and are easily managed by a short discussion with the subject. 3 Their incidence has been between two and three per cent of those tested. Our experience in this regard is closely paralleled by that of Hilgard's (1965) laboratory. Hilgard, Hilgard, & Newman (1961) have related these minor complications to early experiences with anesthesia. We have been able to confirm this hypothesis in some, though not all, of the subjects showing this type of reaction.

The low incidence of even minor complications in our laboratory cannot be ascribed only to the selection of subjects. There is every reason to believe that "normal" student volunteers include a goodly percentage of individuals with considerable psychopathology, indeed some with borderline adjustments. The screening described above is extremely superficial. In view of the large sample involved, we must

3 An incident of this kind occurred with four girls and one boy out of 20 student volunteers who took part in a group induction session and reported headaches and dizziness following the test. When we discussed the experience with these subjects, we learned that they had all come together in one car. During the ride, the boy had been entertaining the four girls with a story about a friend who had been hypnotized by an amateur hypnotist and could not come out of trance. In view of this discussion we were no longer surprised at the subjects' responses. In each instance, the symptoms were resolved once the matter had been aired. It is interesting to note that one of these subjects did not enter hypnosis during the initial session, but with two additional sessions is now capable of achieving deep somnambulistic trance.



conclude that at least some seriously disturbed individuals have been hypnotized without any untoward consequences.

The absence of serious complications in our work may plausibly be attributed to the experimental setting in which it is carried out. Subjects are usually paid for their services; sometimes participation in such studies is a course requirement. The focus is not on the subjects' problems but on the phenomenon investigated, much as in studies of perception, memory, or learning. Subjects are not encouraged to relate material relevant to their life situation. Even when phenomena such as age-regression and dream induction are studied, the material is treated in an essentially neutral experimental manner. The relationship of the research staff to the subject is friendly, but relatively impersonal, when compared with a therapeutic relationship. In summary then, it seems that the induction of hypnosis itself does not lead to untoward consequences if it is perceived as relatively episodic and nonpersonal, viz. if the subject does not expect to be changed in any way and does not perceive the procedure as directed personally toward him.

Hypnosis in a nontherapeutic context: amateur hypnotists

That trained investigators working in an appropriate setting do not encounter difficulties is perhaps not surprising. But hypnosis is frequently induced by totally untrained persons also. In recent years, there has been widespread interest in hypnosis in colleges and universities, and many students have "played" with it. Despite efforts by college authorities to curtail such activities, a very large number of totally unsupervised trance inductions have surely taken place. These inductions are carried out by untrained and often irresponsible individuals, in a context which does not have the obvious safeguards of the laboratory. It is difficult to estimate the incidence of complications arising from such inductions, because minor difficulties would certainly not be reported. On the other hand, serious complications might be hard to conceal and would impel the participants to seek help. Yet, although many educational institutions have active and alert health services, instances of serious problems arising from these activities are hard to find. I have raised this question with many colleagues in departments of psychology, who are frequently consulted by students about a wide variety of issues. Here again, serious complications have rarely come to their attention.

The infrequency with which clandestine hypnotic "experiments" have resulted in demonstrable difficulties is striking. Nevertheless, such cases do occur. Because of my interest in hypnosis and the



laboratory's activities in this area, a few have come to my attention. One student, having been given a hypnotic suggestion to stop smoking, found himself eating compulsively. Another experienced an anxiety state, apparently precipitated by a classmate's hypnotic suggestion that he would feel compelled to study for his examinations. Two other instances were reported by psychologically untrained individuals who had hypnotized their wives and given quasi-therapeutic suggestions. In both cases, the suggestions were such as to affect the relationship between hypnotist and wife. One of these involved a dentist, who utilized hypnotic analgesia in his practice. His wife urged him to give her suggestions to lose weight. The dentist refused repeatedly, always advising her to see her physician and be put on a diet instead. Finally, the dentist agreed to hypnotize her, but instead of suggesting that she lose weight, he suggested that she would consult her physician the next day for a diet. That evening the wife was troubled by an itching sensation, particularly pronounced in the perineal regions, which bothered her so much that she awakened her husband throughout the night to complain about it. It is not appropriate here to discuss the elegant way in which this transient symptom formation dealt with the situation. It is clear, however, that the dentist tried to use the hypnotic relationship in order to have his wife carry out an action she had repeatedly refused. He would surely have been better advised to deal with the situation in another way.

One type of difficulty deserves particular mention because it is a common source of concern to patients when the subject of hypnosis is brought up: namely, a refusal on the part of the subject to awaken when the hypnotist wishes to terminate the session. I have observed this phenomenon only a very few times, and it usually seems to involve the clandestine hypnotic experiments of students. In these cases, the refusal to awaken followed a situation where the subject had been antagonized by the hypnotist's behavior. This response is an almost ideal passive-agressive maneuver, which allows the subject to express hostility toward the hypnotist in a manner consonant with the hypnotic situation. When the inexperienced hypnotist encounters the subject's refusal to awaken, he will tend to become anxious and communicate his anxiety, thereby reinforcing the subject's behavior. The subject may go deeper into the trance state and become unresponsive to the hypnotist as the latter becomes anxious and forcibly tries to awaken the subject. What may have begun as a way of expressing aggression for the subject may become a reaction to an anxiety-provoking situation where the trance state is used as a means of escape. Under these circumstances, the more the hypnotist tries to rouse the subject, the



more unresponsive and lethargic he will become. In the instances I have seen, the impasse was readily resolved when another hypnotist calmly proceeded to establish communication with the subject. This is done by essentially re-inducing hypnosis, using a procedure such as arm levitation. The initial response may take as long as ten minutes to obtain in this situation, but thereafter it is a simple matter to resolve the difficulty and terminate hypnosis. 4

This situation does not seem to occur with experienced hypnotists, probably because they do not become disturbed by slow awakening, and thus the impasse described above does not develop. However, it does occasionally happen that subjects require, for reasons of their own, a certain amount of discussion prior to terminating the trance.5 A number of cases have been studied by Williams (1953) in an excellent summary. As he points out, the appropriate manner of dealing with these situations is through an understanding of the dynamic factors involved.

Thus, the use of hypnosis by untrained individuals can indeed result in complications. However, the incidence of serious reactions observed is remarkably low, considering how many people must be involved in amateur hypnotic "experiments" at one time or another. The relative infrequency of complications in these cases may be ascribed to two factors. First, "playing" with hypnosis is usually episodic, in the sense defined above. Neither the hypnotist nor the subject expects any permanent changes to result. In this respect, most amateur hypnosis resembles the laboratory rather than the therapeutic situation. This particular condition was not fulfilled in several of the instances described above, where problems did arise. Second, most amateur hypnotists recognize their own lack of training and this probably acts as a safeguard in most cases, although it can create problems of its own, such as the subject's reluctance to awaken. The nervous amateur hyp-

4 Despite statements in the literature to the contrary, it is possible to establish communication with a subject in deep hypnosis, even when he has been hypnotized by someone else, and even when he is responding only to the voice of the first hypnotist. It is essential to proceed in a deliberate and calm manner. Obviously, the task is facilitated if the subject already knows that the second individual is competent in hypnosis.

5 For example, one subject did not wish to awaken at the conclusion of an experimental session. This reaction was discussed with him during the continuing trance. He talked briefly about a forthcoming examination the next day, and awoke without further difficulties. In this instance, the subject's reluctance to awaken appeared related to his wish to evade the examination rather than to the specific interaction between himself and the hypnotist. However, I believe the type of impasse described in the text would nonetheless have resulted if the experimenter had become unduly disturbed.



notist may well stop when his subject becomes defensive and displays peculiar behavior. Thereby he may avoid difficulties which the professional, eager for signs that he is reaching critical depths of the personality, runs forward to meet.

Hypnosis in a therapeutic context: the effects of induction

The apparent low incidence of complications found in the laboratory, and even in the inexperienced hands of amateurs, is in sharp contrast to the relatively high number cited by many experienced therapists. Particularly impressive are the fairly severe anxiety reactions which may occur in response to the induction of hypnosis as such, when carried out for therapeutic purposes (Gill & Brenman, 1959; Kline,1953; Meares, 1960; Rosen, 1953; Weitzenhoffer, 1957; Wolberg, 1948). It is remarkable that a simple induction procedure, which seems so free from complications at the laboratory, can evoke dramatic reactions when undertaken in a therapeutic setting.

The difference seems to be related to two aspects specific to the therapeutic relationship. First of all, it is not episodic. Hypnosis is induced by a therapist in the hope of making a relatively permanent change in the symptoms which led the patient to seek treatment. The patient is necessarily ambivalent about this goal. He certainly seeks relief from his symptoms, but they also serve some purpose which makes them difficult to abandon. Thus, the induction of hypnosis may represent a perceived threat to the particular mechanism of adjustment employed by the patient. It is this threat which may be responsible for the observed attacks of anxiety.

This clinical impression is illustrated by two patients who, despite overt cooperation, were unable to enter hypnosis in a therapeutic situation although they had been deeply hypnotized in an experimental context some years earlier. In both cases, the patient was then assured that no attempt would be made to alter his particular symptoms. Each stated that he could not understand why I should make such a remark, since he had come in search of relief. I repeated the statement, adding that the purpose of this first session was only to test his ability to enter hypnosis with me, and that treatment would not be undertaken today under any circumstances. Both patients remained apparently uncomprehending, but became able to enter deep hypnosis rapidly.

This point of view is also substantiated by the wide use of hypnosis in dentistry, purely for the purpose of analgesia. Here, complications from the induction procedure are rarely observed. The induction of hypnosis by the dentist is an episodic event. It is seen by both dentist and patient only as a technique to ease the discomfort of dentistry,



with no expectation that any permanent attribute of the patient will be altered.

Some instances of dramatic anxiety reactions to hypnosis, which I have had the opportunity to observe in a therapeutic context, can best be understood from another point of view. The patient seizes the opportunity to communicate a wish for the therapist to be concerned about him. His reaction is not essentially different from any other dramatic nonverbal communication. In such cases, there is usually a transference issue relating to the use of hypnosis and its meaning to the patient. For example, the therapist may decide to employ hypnosis because of his own concern that the patient show improvement. Detecting this concern, the patient becomes anxious, and communicates his anxiety by having a panic reaction.

For this reason, I have become convinced that the appropriate management of such a reaction is to deal with it in the hypnotic state. To awaken the patient, as has been suggested by Gill and Brenman (1959, p. 20 ff.), is less satisfactory. To the patient, the awakening may mean that the therapist is unable to deal with the reaction in hypnosis. Thus it will tend to make him resist subsequent attempts to induce hypnosis. If the reaction is managed without attempting to awaken the patient and interpreted appropriately, and if counter-transference problems are absent (see below), it does not interfere with the subsequent use of hypnosis in treatment.

In most cases, then, the anxiety reactions arising from induction may stem from the patient's perception of the reasons for inducing hypnosis, and of its non-episodic effect on his life, rather than from any specific suggestion. It seems likely that individuals who are concerned about "being controlled" may well experience hypnosis as a very disturbing event if it is carried out in an authoritarian fashion. Apparently some borderline paranoid individuals can be sufficiently disturbed to become overtly psychotic. Occasional reports of this type have appeared in the literature (Mayer, 1952; Meares, 1960; Raginsky, 1956; Rosen, 1957, 1960, 1961; Weitzenhoffer, 1957). I have not seen such cases, perhaps because both I and individuals trained by me tend to be cautious with subjects showing paranoid tendencies. In addition, our failure to observe these reactions may be due to the difficulty of inducing hypnosis in such individuals.

Hypnosis in a therapeutic context: reactions to suggestion

Views of authorities on the potential complications of therapeutic hypnosis differ drastically. Erickson feels that complications are essentially nonexistent, because "the unconscious mind will protect the



individual from accepting suggestions detrimental to his adjustment." 6 Rosen (1959), on the other hand, has pointed to the serious consequences of incompetent treatment. Levitt and Hershman (1961; 1963), basing their findings on a questionnaire survey of 301 practitioners employing hypnosis, report that

better than 27% of the hypnotists in the sample reported that they had, in one patient or another, observed an unusual, unexpected, and probably alarming, reaction to hypnosis, either during the state itself, or immediately afterward.

By far the most common reaction was some sort of emotional upset, including anxiety, panic states, or depression. The only other frequently reported kind of symptom included minor physiological phenomena like headache, vomiting, fainting, dizziness, etc., either during or immediately after hypnosis. Other reactions which were noted by at least three respondents were crying and hysteria, loss of rapport during hypnosis, excessive dependency on the hypnotist, and difficulties resulting from inadvertently given suggestions. There were five cases of overt psychosis immediately after hypnosis, and five instances of difficulties with women patients involving sex (1961, p. 6).

Unfortunately, it is difficult to interpret this type of report. On the one hand, the reported incidence may be too low. Many workers, especially the less competent ones, may conduct inadequate follow-ups and may fail to recognize untoward sequelae because of their personal needs. For this reason the best-trained workers may report the most complications, while perhaps encountering the fewest. Indeed, Levitt and Hershman (1961) found that 43 per cent of the psychologists and psychiatrists reported complications, as opposed to 27 per cent of all the other respondents. 7 This may be taken as an indication that the incidence of complications reported by the others is too low.

On the other hand, those individuals most concerned about potential complications may observe them precisely because of their very concern. It is generally recognized that patients tend to provide data consistent with the therapist's expectations. It could also be argued that the population of patients seen by the 301 practitioners must be huge indeed and the number of difficulties reported is thus comparatively small. For that matter, similar complications might be observed in the reaction to any medical treatment. 8

It is also possible that difficulties quite unrelated to the hypnotic

6 Erickson, M. H. Personal communication. 1960.

7 There were only 28 psychologists and psychiatrists in the sample.

8 For example, during a double-blind study of a new drug, we encountered two cases of glomerulonephritis. The drug was promptly discontinued but we later learned the particular patients' dose had been a placebo.



intervention may be ascribed to hypnosis. We nearly made this mistake some years ago in a very carefully conducted study of the effect of hypnotically induced anxiety on blood chemistry. After a careful psychiatric evaluation by independent psychiatrists, and careful training, the subject abruptly left school two days prior to the scheduled experiment. At that point, he did not know the nature of the experiment. Had he left two days later, we would have been seriously concerned as to whether we had been responsible for his personal difficulties.

Among the most feared complications of hypnotic therapy are the negative reactions which may result when symptoms are treated by direct suggestion. Psychiatrists have largely abandoned this procedure since the early 1900's, because it is felt that such cures tend to be transient, and that patients may be left with new problems worse than their old ones. Nevertheless, there is every reason to believe that general practitioners of medicine, as well as a large number of totally untrained, so-called lay hypnotists, employ direct suggestion with many patients. I am again impressed by the very small number of instances of this kind that have been reported. To be sure, this low incidence is hard to evaluate. It is possible that many unfortunate results have not come to the attention of psychiatrists; it is also possible that we have over-emphasized the complications resulting from suggestive cures. The generally accepted psychiatric view is based on a very small number of cases. Naturally, each time one sees an instance of symptom substitution, one feels that this is exactly what is to be expected. On the other hand, one may tend to disregard reports of cures by direct suggestion in which no complications have arisen.

It is possible that under some circumstances certain individuals will obtain permanent relief in this manner while others could be made worse. Perhaps it is time to study systematically not whether complications arise, but rather the kind of situations where direct suggestion may be appropriate as opposed to those where it is not. Recently Meares (1960) and Pulver 9 have independently suggested the need for a re-evaluation of suggestive therapy from this point of view.

The use of hypnosis in insight therapy

Special difficulties may arise when hypnosis is used in the context of insight therapy. Little has been written on this subject, probably because few psychiatrists use hypnosis extensively for this purpose. I have personally been impressed by a few informally-reported cases, involving psychiatrists who used hypnosis occasionally during military

9 Pulver, S. Personal communication. 1961.



service. These colleagues, usually highly sophisticated and analytically trained, seemed to forget their knowledge of psychodynamics when they utilized hypnosis. They seemed to have been misled by the aura of strangeness which surrounds hypnosis into believing that it suspends the ordinary principles governing interpersonal relationships. But there is no doubt that all the usual problems of transference and counter-transference remain with us when we use hypnosis. The cases that I have personally observed where difficulties arose generally involved counter-transference, and their essential complications were not qualitatively different from those encountered in any form of insight therapy.

Hypnosis may accentuate counter-transference problems by its very nature. Acting as a hypnotist, the therapist may find it hard to maintain the distance which is necessary if he is to be aware of his own reactions. Even the decision to use hypnosis, and the point in treatment at which it is employed, require careful consideration. All too frequently, the use of hypnosis is primarily in the service of the therapist's needs. Another source of difficulty is the temptation posed by the material elicited under hypnosis, which the patient may not yet be able to tolerate in awareness. It is important to avoid bringing such material forcibly to his attention. Its use must be carefully timed, as all interpretations need to be.

The use of hypnosis in insight therapy as a technical device is not essentially different from other technical procedures such as free association. Nevertheless, it is often seen in a very different light. When the therapist finds a patient unable to free associate, he tends to view this as a patient problem. However, when the patient is unable to enter hypnosis, the therapist may feel a blow to his own narcissistic needs. One says, "The patient could not free associate," but "I could not hypnotize the patient." This confusion necessarily leads to the familiar difficulties encountered whenever the therapist confuses who does what and to whom. That is, the complications arising from the use of hypnosis in insight therapy seem to be indistinguishable from those arising in the course of insight therapy in general.

The effect of hypnosis on the therapist

Rosen (1959) has reported that a number of physicians who have used hypnosis have developed serious psychopathology, usually of a paranoid nature. On the other hand, Pulver and Smith (1965), reporting on their experience in teaching hypnosis, failed to find such difficulties; several other colleagues who have been active in teaching hypnosis in medical school settings have not encountered them either. I



have seen only one such case. It is clear, however, that counter-transference problems may be accentuated by hypnosis. In some instances, therapists have used hypnosis in the service of neurotic needs. Some examples of this kind have recently been summarized by Lindner (1960). Several authors report (e.g. Guze [1956]; Meares [1960]) instances where therapists derive some sort of sexual gratification from the induction of hypnosis. Clearly, problems of this kind must be resolved if hypnosis is to be used effectively. Continued vigilance is necessary to be certain that one is meeting the patient's needs rather than his own.

Overall evaluation

It is apparent that, although hypnosis can be a dangerous procedure, its difficulties are not inherently mysterious. In some situations, complications seem to occur very rarely. These include the setting of the research laboratory, and the analgesic use of hypnosis in medicine and dentistry. It is characteristic of these situations that the subject's encounter with hypnosis is episodic. He does not expect any permanent change, for good or ill, to result from the hypnotic trance. Hence, except for the minor problems that have been discussed, there is little reason to expect serious or lasting complications from the experience.

The chances of trouble are much greater when hypnosis is used therapeutically, and indeed it is the therapeutic context which has produced most of the reported difficulties. The mere induction of hypnosis by a therapist can be threatening to the patient's system of defenses, and may result in an anxiety attack. The use of direct counter-symptomatic suggestions may have further consequences, although these are not as well documented as is often supposed. In any event, there is no doubt that the classical problems of transference and counter-transference may be sharpened by the use of hypnosis. To avoid such difficulties, the therapist must not only be alert to the special characteristics of the hypnotic situation, but also to the features which it shares with other therapeutic methods.


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The preceding paper is a reproduction of the following article (Orne, M.T. Undesirable effects of hypnosis: The determinants and management. International Journal of Clinical and Experimental Hypnosis, 1965, 13, 226-237.). It is reproduced here with the kind permission of the Editor-in-Chief of The International Journal of Clinical and Experimental Hypnosis.