Hypnotism is a phenomenon that has been known to science for a long time. Ever since it first came to the attention of medical men, it has been vigorously advocated and defended by some as a panacea; at the same time, with an equal lack of understanding, it has been condemned by others as being without merit, without dignity, and even criminal. In its history hypnotism has run the gamut from public favor to disrepute. Within the past few years a considerable body of knowledge has been built up pertaining to hypnosis, which for the first time is based on sound scientific data. As a result, there has again been a marked increase in interest in this phenomenon both by the public and by scientific groups. The physician is being consulted more and more frequently by patients who ask about, and for, hypnotherapy. It thus becomes important for the medical man to be informed about the possibilities and limitations, as well as dangers, inherent in the use of hypnosis. A lack of understanding on the part of a medical man presents a serious danger to the public. This is especially true in this state, because in the Medical Practice Act of Massachusetts (1) hypnotism is specially exempted; thus, it is possible for persons trained neither in medicine nor psychology to do great harm.
GENERAL CONSIDERATIONS:
It is difficult to define the hypnotic state as such. The concept of what constitutes a trance has changed considerably over the years. When Mesmer in 1778 went to Paris and proceeded to "cure" his patients by means of trances, spontaneously appearing hysteric convulsions were invariably associated with them. Later, it was discovered by one of Mesmer's students, the Marquis de Puysigur, that a satisfactory trance could be obtained without convulsions. In this condition the subject appeared not to be fully awake, yet was able to perform commands in the fashion of a sleepwalker. Upon awakening, he seemed to show no recollection of the events occurring during the trance. More recently Wells (2) and Young (3), respectively, have shown that neither the appearance of sleepwalking nor the amnesia represent essential aspects of the trance. It appears that a definition of the hypnotic trance based upon the description of what takes place in any particular trance is at best confusing. It seems
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best to consider the state of hypnosis a condition characterized by a marked heightening of suggestibility on the part of the subject. ( 4 ) This represents the only aspect of the hypnotic trance which is essential. It is found in every hypnotic state. This state of heightened suggestibility, to which we will refer as the hypnotic trance, permits the hypnotist to elicit certain phenomena. While it will not be possible to discuss them all, we shall try to touch on those which are of interest and importance to the medical man.
No matter how passive the subject appears as he enters the trance, he will continue to respond to suggestions by the hypnotist. Frequently, it will be observed that he will cease to respond to any stimuli other than the hypnotist's voice. This phenomenon has been called rapport (5) and was considered for a long time to be essential to the trance. Young has demonstrated that this is not the case. Unless one suggests to the subject explicitly or implicitly that he hear only the operator's voice, a true trance will be obtained in which the subject nevertheless remains responsive to outside stimuli.
For a long time it has been observed that many subjects will, upon awakening from the trance, have no recall for the events that occurred in the trance. This has been termed posthypnotic amnesia and is one of the most important criteria of a deep trance. However, it is questionable whether this need occur spontaneously in a deep trance. If no suggestions of forgetting have been given the subject while in the trance, and the subject did not believe posthypnotic amnesia to be a feature of hypnosis prior to entering the trance, it will frequently be absent. In considering this phenomenon it is important to realize that the beliefs of the hypnotist play an important role in the trance he is inducing. If the hypnotist believes that posthypnotic amnesia is important, he may easily suggest it unwittingly. The subject in the trance is extremely perceptive of unspoken but implied suggestions, and reacts accordingly.
Because the trance is usually induced by telling the subject "You're going to sleep," and due to the superficial resemblance of the trance state to true sleep, it has been considered by a number of authorities as akin to physiological sleep. (6,7,8) This is not the case. In contrast to sleep, even the deepest hypnotic trance permits the subject to respond to the stimulus of the hypnotist's voice. In a classic experiment Bass (9) has demonstrated that the patellar reflex which disappears during sleep is present in a trance. EEG studies have demonstrated that the characteristic delta waves of sleep are not found in hypnosis. (10,11) However, it has been shown conclusively that sleep may be induced either posthypnotically, or on suggestion during the hypnotic trance. (12) There is some evidence to show that a subject may fall asleep during a hypnotic trance and awaken still in hypnosis. This has undoubtedly contributed to the confusion of the two states.
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One of the aspects of hypnosis, which has done more to incite interest and at the same time to discredit it and to place it in the realm of magic, is the apparent ability of the hypnotized subject to transcend the normal limits of his physical capacity. The last word has not been written about this aspect of hypnosis. However, we can better understand much of what can be achieved in the trance if we consider the difference between the performance of an individual under normal circumstances and of one in a highly motivated situation. Thus, it has been stated that the subject in the trance is able to perform greater tasks of endurance than in the wake state, in such tests as lifting weights, pressing an ergograph, etc. Estimates have run from 300 per cent increase to a conservative 16 per cent found in controlled studies. (13,14,15) However, hypnosis increases the subject's tendency to carry out suggestions. This means he is more motivated to comply with a request in hypnosis than with an identical request in the wake state. It seems that increased performance in the trance is due to increased motivation rather than increased capacity. The author was able to demonstrate in a recent study that individuals, if properly motivated in the wake state (e.g. by money rewards and ego-involvement), were able to exceed their hypnotic performances in every case. (16) It has also been shown that the very spectacular experiments of endurance commonly a part of stage exhibitions, such as placing a man between two chairs and permitting someone to stand on his abdomen, can easily be duplicated with a wake individual. This illustrates how carefully one must choose controls in order not to be misled by apparently spectacular results. Another study which shows this clearly was done by Leuckhardt and Johnston. (17) They were able to demonstrate that a subject in hypnosis eating an hallucinated meal not only went through the motions of eating, but also showed an increase in the volume and acidity of gastric secretion corresponding to that found after an actual meal. However, a control study demonstrated that a wake subject engaged in conversation about food will manifest the same changes in gastric secretion as those brought about by real food or hypnosis.
By these examples we do not mean to imply that all the phenomena which are seen along this line can easily be explained. Heilig and Hoff (18) were able to induce herpes simplex by means of hypnosis, as follows. Three psychopathic women were hypnotized and extremely unpleasant emotional experiences were suggested, inducing great excitement, flushing, etc. At this point the psychiatrist gently stroked the subject's lower lip and suggested a feeling of itchiness such as the subject had felt before in association with the beginning of a cold sore. The subjects were subsequently calmed and awakened from the trance. Over a period of 24 hours the patients reported itching, eventually developing true cases of herpes simplex as proven by rabbit cornea transplantation. Unfortunately,
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as Hull points out in a review ( 4), there was no adequate control done to determine whether the specific suggestion or the general excitement were the etiological factors in the development of herpes simplex. This is especially significant since the patients had previously demonstrated a tendency to develop cold sores. Other studies have appeared which report the production of blisters or ecchymoses as a result of hypnotic suggestion. Pattie, in a review of the literature (19), points out that in the last 50 years only 11 reports have appeared describing the successful production of blisters and these lacked adequate controls. He concludes, "the writer after all this evidence still finds himself in a state of suspended judgment." It would seem that until better control studies are available, open minded scepticism is needed toward all claims of the transcendence of normal physiological capacities due to the hypnotic trance.
Pain is one of the big question marks of medicine and psychology. Undoubtedly it is a combination of both physical and psychological factors. However, it has been proven conclusively that hypnotism is capable of inhibiting the expression of pain. It permits the tolerance of pain which would otherwise prove intolerable. Hypnotism anteceded anesthesia. In an era when ether was yet unknown, men like Braid (20) performed a great many "painless" operations with the aid of hypnotism. However, while the anesthetic agents now in use do not permit the recall of pain under any circumstances, a subject who has experienced "painless" surgery under hypnosis will be able to recall pain in a subsequent trance. Thus it seems that it may not be the pain itself but merely the expression and subjective awareness of pain that is inhibited. Sears (21) was able to demonstrate that while the subject is able to successfully inhibit voluntary expression of pain, objective indices of pain (G.S.R., pulse, etc.) are subject only to slight inhibition. In general, it seems that the greater the voluntary control to which an expression of pain is subject, the greater the degree of its inhibition by the hypnotic trance. Lest we lose perspective in regard to the repression of pain by hypnosis, it must be recalled that other special states show the same phenomenon. It is well known, for example, that a man wounded in the heat of battle may not become aware of his wounds until after the fight is over.
It has been claimed that in hypnosis the time sense becomes perfectly accurate; that a subject in a trance will be able to estimate with precision the length of any period of time. Carefully controlled studies by Klaus (21) indicate that the trance does not materially improve the individual's ability to judge time. While the objective judgment of time is subject to little change, the subjective time perception can be altered tremendously. Erickson and Cooper (23) have shown that in hypnosis like in the dream, a very short period of time may seem like hours.
The function of memory in the trance has been the subject of much
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controversy; however, controlled experiments have demonstrated that recall for recently learned material is not facilitated by hypnosis. On the other hand, Stalnaker and Riddle (24) have shown that the recall for long forgotten memories is improved by between 18 per cent and 259 per cent, with a median of 37 per cent.
Not only does the trance increase, to a moderate degree, the ability to remember things long forgotten, but more significantly, it permits recall of material that has been repressed. Such material is recalled relatively easily in the trance, while in the wake state the resistance may be so great as to require weeks and months to overcome it. In general, it has been observed that in some of its aspects the trance is close to unconscious thinking. With proper suggestion, dreams may be elicited which show the same form of distortion, condensation, symbolism, etc. as real dreams. And, most important, the patient may be able to interpret his own dream while in the trance.
A subject in deep hypnosis may be told that he is again a young child and he will talk, think and act in a fashion strikingly resembling that of a child. This is so convincing as to have been given the name "age regression" or even "ablation". (25) Some authorities have claimed that a subject in this state is in fact functioning again at the suggested age level. Most modern authors, however, agree that this is not the case. Young (26) showed that the intelligence test scores obtained by regressed subjects did not correspond to those which would have been appropriate to the age; in fact, wake subjects making believe that they were at a given age simulated more accurately the test findings of a child. However, the way in which the subject behaves in hypnotic regression is so vivid that acting is certainly not the whole answer. We may think of the subject in the trance acting in response to a hallucinated environment which resembles that of a six year old. He believes himself to be six years old and has a somewhat increased recall of the experiences at that time. For this reason, his actions will be exceedingly convincing. Yet his performance on a test, such as the Rorschach ink blots, will not show true regression. Also, drawings done by him in the state will show "sophisticated oversimplification"(27) and not the features of children's drawings. Nevertheless, the lack of objective validity of age regression does not detract from its great usefulness as a technique in therapy.
Of great importance is the posthypnotic phenomenon. In general all phenomena which can be elicited in the trance can also be elicited in the wake state by appropriate posthypnotic suggestion. According to Erickson (28) the posthypnotic state is a state of temporary hypnosis initiated by the cue to perform the suggested act and terminated automatically at the completion of the act. During this state the subject is not at all passive, there is no rapport (the hypnotist need not even be present), and the
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subject while carrying out the suggestion may be quite busily engaged in an active conversation with someone else. It has been shown that he will, as a rule, rationalize for the actions he is executing in response to the posthypnotic command. (29) From all this it will be seen that here we have a state of hypnosis where the subject is far from an automaton; although he follows suggestions and is in a trance, his eyes may be open and other expressions normal. This need not be the case in the posthypnotic state alone; rather, it is quite easy to induce a hypnotic trance in which the subject is able to initiate behavior, talk normally, and have his eyes open. Indeed, it is only as long as the hypnotist believes that the subject must be passive -- thus unwittingly discouraging any active behavior by implicit suggestions -- that the trance will resemble the classic hypnotic state.
It is not possible in a paper of this kind to discuss all the manifestations of the trance or even the principal ones in detail. We have merely tried to present some of the newer findings about the more significant aspects of the trance. Of all these, the most important features for the development of hypnotherapy have been:
1. The increased tendency to follow suggestions
2. The hyperamnesia for long forgotten memories
3. The ability to better recall material which has been actively forgotten (repressed), due to its close relationship with unpleasant emotional content.
4. The potentiality of the trance for the suppression of pain, as well as the somewhat greater control of automatic functions in hypnosis than in the wake state.
HYPNOTIZABILITY
Anyone considering the use of the trance as a therapeutic instrument must ask these questions; what percentage of individuals can be hypnotized, and how easily? Estimates differ. According to White (30) only about 12 per cent of the population are completely refractory to hypnosis. Another 30 per cent will be unable to get beyond a light trance. However, it must be pointed out that the percentage of subjects entering into a trance depends to a large degree upon the setting in which they are hypnotized. At one time hypnosis was believed to be due to a force emanating from the hypnotist. This notion has been completely discredited. Later, when it became clear that some individuals entered a trance far more easily than others, it was believed that hypnosis was due to the subject's somnambulistic tendencies. Today hypnosis is considered to be the result of a complex interpersonal relationship. (31,32) For this reason some individuals will enter a trance in one situation and not in another. Thus Erickson (33)
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reports a case who became one of his best subjects but required 300 hours of work before entering the trance for the first time. In clinical practice such an individual would, of course, be considered unhypnotizable. Therefore, it is not possible to decide what percentage of the population would, under optimal conditions, be able to enter a trance. There is no doubt that every subject cannot be hypnotized by any one hypnotist. Sometimes a woman, sometimes a man, will be more effective in a particular case. It is clear, however, that under optimal conditions, with an adequately structured interpersonal situation, the overwhelming majority of subjects will enter a trance and some authorities maintain that everyone will.
HYPNOTHERAPY
Originally, hypnotic therapy was based on pure suggestion. The patient was put into a deep trance and it was commanded that his symptom should be gone upon awakening. (34,35) This direct suggestive therapy has affected many spectacular cures, especially in cases of conversion hysteria. The disadvantages of this method are the very high incidence of relapses and the real danger of new and worse symptoms developing. (36) For these reasons this rather naive suggestive therapy is today no longer considered adequate. Unfortunately, in the eyes of many physicians, hypnotherapy has been equated with direct suggestion and for this reason condemned. While we quite concur with the rejection of direct suggestion for most cases, other techniques of hypnotherapy have been developed which show much greater promise.
An early modification of this technique was an attempt to treat the underlying attitudes on which the symptoms were based. This form of therapy was still primarily suggestive. However, since it no longer was concerned only with the symptoms but also with the underlying attitudes, its chances for an effective cure were considerably better. This form of therapy represented a compromise between direct suggestion and the rational common sense psychotherapy fashionable at the turn of the century and used by such men as DuBois. An example of such treatment is given by Prince and Coriat. (37) The daughter of a true epileptic with a morbid fear of the disease developed hysteria epilepsy. In a deep trance she was told that she did not have epilepsy, that her convulsions were based on an unfounded fear, that she should now realize that the fear was the cause of the attacks, etc. This therapy relieved the attacks permanently. One cannot but be impressed by the reports of reliable clinicians around the turn of the century who used such methods. Apparently the fact that the underlying attitudes were at least taken into consideration, combined with the clinician's good judgment, helped to bolster the in-
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dividual sufficiently so that he could get along without his symptom. In this form of therapy one would expect a far more real transference relationship evolving than in those involving pure suggestion. This is undoubtedly an important factor in a patient's "cure". However, the great fault of this technique is that the insight which is given to the patient is not based on a working through of his problem, but rather is based on his acceptance of the therapist's concept of the etiology of his symptoms, which concept may or may not be correct.
In 1887 Sigmund Freud working with Joseph Breuer successfully treated a patient with conversion hysteria using hypnotism without any direct suggestion. (38) In their history-making paper they described the case of Anna, who in hypnosis relived the traumatic incidents which were the etiological factors in the neurosis. The reliving of such incidents was accompanied by the disappearance of the symptoms to which they were related. This marked the beginning of psychoanalysis. The form of therapy was termed by Freud as cathartic treatment or "abreaction." This form of therapy, but with minor modifications, is still in use today, and has proven remarkably successful in the neuroses with traumatic onset found during wartime. The success of this form of therapy is roughly paralleled by that of narcosynthesis. Unfortunately, it has proved disappointing when used with patients who have developed their symptoms over a period of years, such as we are wont to see in civilian life.
Freud soon discovered that catharsis alone was not the primary curative factor. Insight and recovery of repressed memories were found to be of paramount importance. (39) Accordingly he altered his technique. However, he soon found that not all patients could be hypnotized and thus abandoned hypnosis in favor of free association as a means of obtaining analytic insight. Within recent years analysts have again been utilizing hypnosis, but now 40 years of accumulated psychoanalytic experience is available to the therapist. A technique of hypnoanalysis has been developed which, according to its proponents, achieves results comparable with those of psychoanalysis but has the immeasurable advantage of consuming a far shorter period of time. (40,41) This form of therapy is not content with merely permitting the patient to abreact nor with the simple recovery of repressed material. The material which is brought out in the hypnotic state is worked through with the patient in the waking state. Furthermore, the transference relationship is analyzed. The whole process may be considered analogous to orthodox analysis. The primary modification is that hypnosis is used to facilitate free association with a corresponding saving of time, especially with respect to the long unproductive periods of resistance otherwise encountered. It must be pointed out, however, that many analysts claim that this treatment lacks the thoroughness of the classic analysis. The claim that the transference reaction is
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never resolved is also made, but this seems no more justified here than in analysis itself. The fact is that to our knowledge no study has ever been made evaluating the comparative success of hypnoanalysis and classical analysis. It would seem to us that such a study would be very worthwhile.
Perhaps the most promising and certainly one of the most interesting approaches has been that exemplified by Milton Erickson. To him hypnosis is a tool which can be used to achieve certain effects but the basic therapy whether with or without hypnosis depends upon a thorough grasp of the psychodynamics involved. He demonstrated clearly that conscious insight is not essential in all cases, because reintegration may be achieved at another level. However, there must be a reintegration. In the paper, "The Successful Cure of an Hysterical Depression by a Return to a Critical Phase in Childhood"(42), a patient in hypnosis is brought back to a state which subjectively resembles that of early childhood. In the trance, the etiological factors are brought out and reintegrated in a new way, resulting in cure. Or, in another case (43, 44), in a patient with ejaculation praecox, in hypnosis a complex was artificially induced which was a symbolic representation of the underlying problem, and upon the removal of this artificially induced complex, the original symptom disappeared.
In certain types of conditions hypnotherapy may represent the treatment of choice. Thus, for example, Robert Lindner in his well-known book "Rebel Without Cause" (45) gives the history of the hypnoanalysis of a criminal psychopath. He points out that for this type of patient hypnotherapy represents one of the few, if not the only, therapeutic approach. Another area in which hypnosis may prove promising is with the alcoholic. While the alcoholic is drinking he is resistive to therapy, and his adjustment is such that if he is under therapy while sober he will begin to drink as soon as he experiences any anxiety, thus making effective therapy practically impossible. The most successful attempts to cure alcoholics on a large scale have been made by Alcoholics Anonymous (46), operating predominantly on a faith-cure principle, and psychiatry using directly oriented therapy. Unfortunately, negative suggestions, especially posthypnotic suggestions, are not as effective as positive suggestions, and the success with hypnosis alone has been rather limited. On the other hand, the author was able to "keep dry," and therefore make available for psychotherapy, a patient who had proven resistive to any and all forms of treatment. This was done by the simple measure of compelling her by posthypnotic suggestion to take Antabuse regularly (she had previously discontinued the drug shortly upon release from an institution). In this type of usage hypnotism is to be considered not the therapy, but a minor, quite valuable adjunct.
Another form of hypnotherapy which is being employed extensively, especially in Germany, is "Active Hypnose"(47) or "Autogenes Train-
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ing". (48) With this technique, originally devised by J. H. Schultz and further developed by Kretschmer, the patient is taught to induce a trance in himself. As a rule, this trance is restricted to two minutes. The procedure is a form of training in which the patient is taught first how to relax one hand, then to experience a feeling of heaviness in the hand, then a feeling of warmth -- until gradually he learns to relax his whole body and to enter this short trance at will. This is done in several sessions with a considerable amount of practice on the patient's part at home. The rationale of this therapy is that anxiety is accompanied by a state of muscular tension which is perceived by the individual, leading to more anxiety, more tension, and thus forming a vicious circle.
The recent use of Tolserol in cases of anxiety is based on a similar rationale. Muscular relaxation is brought about leading to a diminution of anxiety. In "Active Hypnose" the patient is taught to induce this relaxation at will. This, then becomes a technique which he has at his disposal at all times, and with which he can prevent a state of tension which would become unbearable. The success with this form of treatment has been excellent, especially in patients with periodic anxiety attacks. It has also been very useful in those cases where an external reality situation was present from which the patient could not escape. While this is a symptomatic form of therapy, it is under the patient's control, and so the formation of secondary symptoms is usually not encountered.
The technique of "progressive relaxation" developed by Jacobson (49) is based on a similar rationale as that of Schultz. However, Jacobson explicitly denies the use of hypnosis, working only with the concept of relaxation.
Another field in which suggestive therapy has proven promising is obstetrics. The famous Reed (50) studies at Yale, while denying explicitly the use of hypnosis, certainly are based to a large degree on suggestion and when one reads the reports of the author one wonders if he is not inadvertently using, a true trance. Heron and Abramson (51) report a study where hypnosis as such was used in an attempt to facilitate labor. In their study a hundred patients were used, which were not selected as to their hypnotizability but only on the basis of their willingness to cooperate. (This represented about 90 per cent of the patients asked.) In comparing these with 88 controls, they state that the duration of the first stage of labor was reduced by about 20 percent and less drugs were needed to control pain. "This is an average figure and does not stress the spectacular results which are obtained in some patients."
Lately there has also been a good deal of interest in hypnosis by dentists and many reports (52) have come out which show dramatic results using hypnosis as the sole anesthetic. There is some question, however, whether it represents a worthwhile investment of time and labor in view of the relatively small gain.
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CONCLUSION:
We have tried to outline some of the potentialities of hypnosis as a therapeutic tool. The possibilities have not been exhaustively covered but we hope we have demonstrated that hypnosis and suggestive therapeutics in the classical sense are not the same. Today hypnotherapy is viewed as a cooperative effort. The focus of therapy is on the psychodynamics of the patient. Even in deep hypnosis we are dealing with a true interpersonal relationship. The subject even in a deep trance is quite capable of resisting suggestions if they run counter to the needs of the superego. In fact there are some indications that many superego inhibitions are increased during the trance. (53) In evaluating experiments involving suggested crimes one must not forget that the subject trusts the hypnotist prior to hypnosis and continues to do so during the trance. For this reason he will do many acts which in another setting might be evaluated differently.
This raises the question of the dangers inherent in the hypnotic trance. The most important single difficulty is shared by hypnotherapy in untrained hands with any other form of "wild analysis" or "wild psychotherapy." In other words, any form of psychotherapy in untrained hands may result in problems more serious than the original symptoms. The dangers of patients acting out in such therapy, especially in response to poorly handled transference relationships, are well known. More specifically dealing with the trance state itself, there have been several cases on record where fairly severe reactions were precipitated by incompetent handling of a trance. (30,54) One finds in these cases that the subject had been an individual just barely getting along prior to the experiment and an inapt suggestion brought out the underlying pathology. (It would seem to us that the same cautions apply to hypnosis as to other attempts to help the individual, only more so.) One element inherent in the trance must be thoroughly understood by the hypnotist. The subject, when he enters the trance, places his trust in the hypnotist. If the hypnotist betrays this trust in any way, (and this may be done unwittingly), if he does not respect the subject's integrity as an individual, then the subject may easily become seriously disturbed. In the same sense any sign on the part of the hypnotist that he is losing control of the situation may disturb the subject. This can easily be understood in view of the fact that the subject believes himself to be dependent upon the hypnotist while in the trance.
Just as certain conditions are especially suited to hypnotherapy, others are contra-indications to it. Thus, if one is dealing with an individual whose primary problem is one of passive dependency, it would be rather unwise to expect to help him with hypnotherapy.
In this paper we have tried to show that hypnosis can be a valuable therapeutic tool in competent hands. It is not a panacea, and one cannot
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assume that when a deep trance is achieved the patient is thereupon immediately cured. Like every other form of therapy it carries certain unique advantages, some dangers, and has many inherent limitations. Especially because of the latter two aspects of hypnosis does it behoove the physician to concern himself with this form of treatment; if he does not, others, lacking understanding of these inherent dangers and limitations, will, by default, be put into a position whereby they may do much harm.
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