On the construct of hypnosis: how its definition affects research and its clinical application

MARTIN T. ORNE

The Institute of Pennsylvania Hospital and University of Pennsylvania, Philadelphia

Although there is a good deal of consensus about hypnotic phenomena, controversy persists about the nature of hypnosis and even about its utility as a construct. The purpose of this paper is to explore those aspects of hypnosis which distinguish it from other phenomena and to suggest a way of defining it based on these characteristics. Since it appears that many of the misconceptions about hypnosis and even much of the continuing controversy about its nature follow from the manner in which it is defined, a clarification of this issue may therefore facilitate systematic inquiry into the nature of hypnosis un the one hand and lead to a more rational clinical application of the technique on the other.

HYPNOSIS AS BEHAVIOURAL COMPLIANCE

Much of the literature presents hypnosis as a means by which the hypnotist may control the behaviour of the subject. If the average layman is asked what is most typical of hypnosis, he may respond that it 'puts the subject under the power of the hypnotist,' or some more acceptable paraphrase. This widely held belief reflects itself in the parent who takes his teenager to a hypnotist in order that some behaviour he finds onerous might be altered by suggestions or by the dentist using hypnosis to control pain giving a patient the suggestion that he must brush his teeth. Such instances involve an attempt to use hypnosis to modify behaviour that the individual is unwilling but not unable to modify on his own.

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In my view, hypnosis is a very poor technique for such a purpose. It not only tends to be unsuccessful but also interferes with the effective application of the technique. There is no evidence currently available which would indicate that hypnosis increases the amount of control the hypnotist is able to exert on the behaviour of the subject. I typically illustrate this point in lectures to students by, at the very onset, asking one student to give me his left shoe, another his watch, a third to exchange spectacles with someone beside him, a fourth his wallet, and so on. Provided these requests are made with the expectation that they will be followed, everyone complies despite the unusual and somewhat embarrassing nature of the demands. As soon as these items of behaviour are carried out, I ask the volunteers whether they had been hypnotized. Characteristically they appear somewhat puzzled by the question and then indicate that this, of course, had not been the case. The demonstration allows me to point out to the group that if I had first hypnotized the students and they had then carried out the very same behaviours, this fact would have been taken as reliable evidence that they were both hypnotized and under my control. As had just been graphically illustrated, students will, if asked, carry out these implausible behaviours without hypnosis.

One simply does not normally test the good natured willingness of a student to comply with the request of a lecturer. When the volunteer is asked why he took off his left shoe, he will explain he felt somewhat awkward, didn't really know why he was asked for the left shoe, but assumed that since I was lecturing to the class there must have been some good reason for the request and he therefore did as he was asked, preferring to embarrass himself rather than to embarrass me. Such a report is, of course, quite different from the experience of a deeply hypnotized individual in the same situation, but this does not change the fact that the awake subject will carry out every request that might be asked of the hypnotized subject.

The relevance of such a demonstration becomes clear when one considers that hypnosis is never carried out in a vacuum. For example, if over lunch I began to suggest to an acquaintance that his eyes are growing heavy and he is growing sleepy, he will begin to wonder what is wrong and he might ask me whether I am feeling all right. It is simply not possible to induce hypnosis without an appropriate context in which to do so. There are only three major contexts in which I have seen hypnosis induced: in the context of therapeutic treatment, in the context of an experiment, and finally in the context of a lecture demonstration or entertainment.

If one wants to ask whether hypnosis increases the hypnotist's behavioural control over the subject, one must first establish what is the baseline behavioural control in that particular context without hypnosis. I have already touched upon the lecture context which permits far more behavioural control than is generally tested. The entertainment context is quite similar. Volunteers typically are willing and indeed eager to make fools of themselves to the amusement of all. Television programs such as Truth or Consequences, Candid Camera, or People are Funny are classic examples that were built upon the fact that volunteers will carry out bizarre requests in the context of an audience participation program. This simple fact has much to do with the willingness of individuals to make fools of themselves on stage when hypnotized, and

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even spontaneously (or on request) to simulate hypnosis under these circumstances. A classic literary example of this kind is reported by Mark Twain in Tom Sawyer.

Consider now the experimental situation. Here a subject volunteers to assist an investigator to determine some important scientific fact. One of the rules of the psychological experiment particularly is that the subject will do what is requested of him without inquiring as to the purpose since to do so might invalidate the experiment. The consequences of these 'rules of the game' are, however, profound. They are illustrated by a simple experiment the reader might try for himself. Make a list of some 20 casual acquaintances and randomly assign them to two groups of 10. Then approach the first group and ask them, 'Will you do me a favor?' Most individuals, in the United States at least, will answer in the affirmative. Then say, 'All right. Please do ten pushups.' The acquaintances will tend to laugh and say, 'Is there something wrong with you? Why would you ask me to do such a silly thing?' and it is the rare case indeed where one actually complies.

The other 10 casual acquaintances are then approached with the question, 'Will you do me a favor?' and then, when it is again answered in the affirmative, another request is made, 'Will you take part in an experiment?' A typical response is, 'Okay, why not.' A pad of paper is then produced, the acquaintance's name is written down, the date and the time noted, and then he is told, 'All right. Now do ten pushups.' The acquaintance, who is now a 'subject' will typically respond with, 'Where?'

Elsewhere I have discussed the implications of this simple observation for an understanding of the psychological experiment (Orne l962, 1973). In this context it is sufficient to point out that the psychological experiment greatly increases the willingness of individuals who have agreed to participate to comply with any directions. We have been singularly unsuccessful in finding behaviours which subjects will refuse to carry out when the request is made in a way that expects compliance (Orne and Evans 1965). Again, the work of Milgram (1965) illustrates the range of behavioural control inherent in the experiment, though our conclusions about his findings are quite different from his (Orne and Holland 1968).

Finally, there is the therapeutic context. This context is perhaps the one with the greatest degree of behavioural control. Thus, the sick or troubled individual seeking help is highly motivated to believe in the competence of the therapist to provide this help and is willing to carry out almost any behaviour that is requested of him, presumably to provide the sought after relief. The degree of 'blind obedience' that is inherent in the relationship is often not obvious to the physician because the requests he makes are, in his mind, totally rational since he--hopefully--is clear as to why a given procedure is being carried out. From the patient's point of view, this is often not clear. Consider such typical examples as when the physician percusses his back, listens to his abdomen with a stethoscope, examines his ear lobes when the patient complains of pain in the big toe. Most patients must accept on faith that the doctor's behaviour is rational and the requests appropriate. The patient assumes that the doctor knows what he is doing and does what is asked of him. Indeed, it is difficult to conceive of any procedure that is more painful, more embarrassing, and more tedious than many of the medical procedures that are routinely carried out with cooperative patients. If one

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considers what patients are ready to do simply because the doctor indicates that it is necessary for their health to carry out a particular examination, the kind of behavioural compliance characteristic of hypnosis is put into its proper perspective.

While this issue is an important one and deserves more detailed explication, it seems sufficient in this context to emphasize that there is no evidence that hypnotized individuals are more willing to carry out simple requests from the hypnotist because they are hypnotized. This has been documented in experimental contexts with some care when some time ago I summarized the evidence (Orne 1966) that, contrary to my own early views (Orne 1959), the hypnotized individual is not necessarily more motivated than the unhypnotized individual to comply with the requests of the hypnotist. In this I was particularly impressed with the original but oft ignored observation, originally made by London and Fuhrer (1961), that unhypnotizable subjects are more willing to exert themselves prior to hypnosis or following exposure to a hypnotic induction procedure than hypnotizable individuals. A similar tendency was reflected in the higher pain threshold of unhypnotizable subjects prior to an experiment (Shor 1964).

WHY IS HYPNOSIS A COMPELLING PHENOMENON?

Consider for a moment what occurs with a responsive subject following a simple hypnotic procedure administered by a comparative stranger. Following arm levitation, a number of standard hypnotic phenomena are suggested and the specific suggestion that on awakening, 'You will forget what has occurred during hypnosis until I start writing down notes, ' is made. Further, the hypnotist adds, 'Each time I remove my spectacles your right hand will lift to smooth your hair.' Hypnosis is then terminated, and when asked what has occurred, the subject is able to describe the experience of watching the hand and seeing it begin to float upward, but insists that he is unable to recall more than one or two disjointed events that occurred subsequently. Despite encouragement to remember, the subject continues to assert that he simply cannot recall more of what occurred. During his conversation, I twice remove my eyeglasses and each time he smooths his hair. Finally I begin to take notes about what is being said, and suddenly, with a somewhat puzzled expression followed by a smile, the subject says, 'It suddenly came back to me ... Now I remember . . . .' Indeed, the subject does now remember and reports systematically most, though not necessarily all, that transpired.

Such a series of events holds great fascination for the observer, be he layman or psychologist. What is it that makes this series of events interesting? The subject's actions taken separately are unremarkable. He may have raised his hand somewhat more slowly than usual. When told to place his hands together and that he would be unable to take them apart, he did not separate them until told to do so. On awakening he reported that he did not remember what had happened and then twice smoothed his hair--a trivial action--all of which again merely involved in some sense doing what he had been asked to do.

The trivial items of behaviour as such do not cause us to call this set of events hypnosis: rather it is the inference that subjective events are reflected in these be-

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haviours. The subject was not instructed to raise his hand slowly; rather he had been told his fingers and arm were getting light and would float upward. The observer may wonder whether the subject actually experienced his hand and arm becoming light--which expressed itself in the hand slowly lifting upward--or whether he simply chose to raise his hand slowly. Similarly, when on awakening the subject says, 'I can't remember what happened,' the observer may be curious as to whether that is true or whether the subject really does remember and chooses to act as though he cannot. Again, with the posthypnotic response the issue is whether the response of smoothing the hair is carried out without the subject's awareness, as it appears to be, or whether it represents a purposive going along with the hypnotist's request.

If the observer learned that he happened to have come upon a rehearsal of a play and the participants were actors, he would quickly lose interest since there would be no reason to assume that the observed behaviour had reflected changes in the individual's subjective experience. In other words, it is not the overt behavioural compliance that is elicited by the hypnotist which distinguishes the phenomenon.

The alteration of subjective experience in hypnosis

What characterizes the hypnotizable subject is not the tendency to comply with any and all requests but rather the specific tendency or ability to respond to suggestions designed to elicit hypnotic phenomena. In other words, what strikes the observer is the profound change that can apparently be brought about in the experience of the hypnotized subject which suggests that hypnosis must involve some basic and profound alterations. Paradoxically, the induction of hypnosis does not require an intense interpersonal relationship nor even an intense wish on the part of the subject to be hypnotized. Furthermore, the induction procedure is hardly impressive, and it strikes an observer as most implausible that such a simple set of operations would lead to such profound consequences.

If hypnosis were the consequence of some drastic procedure, be it a drug, an intensely stressful experience, prolonged isolation, or some other obviously significant intervention, we would find it easy to understand and accept. It is the paradox between the apparently trivial induction procedure and the apparently dramatic consequences which is responsible for much of the controversy which has surrounded hypnosis since its discovery.

HYPNOSIS --ACTUAL STATE OR ELABORATE HOAX?

The reactions to hypnosis that evolve among both serious lay observers and scientists seeking to understand hypnosis appear to polarize into one of two major categories (example: Sutcliffe's distinction between 'credulous' and 'skeptical' views, 1961). One group seems convinced that hypnosis is a uniquely powerful state which results in almost magical abilities. They report that hypnotized individuals can perform feats of strength and have control of both body and mind beyond the ken of the normal individual. Not only can cures of psychological problems be effected but even a wide

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range of bodily processes can be altered in a unique fashion. Finally, in novels and the lay press this view leads to the imaginative leap that the hypnotist is able to exert a wide range of control over the subject which, if not restrained by ethical strictures, would make it possible to compel the hypnotized individual to do whatever the hypnotist might desire. Scientifically, the extreme-state view tends to be associated with the conviction that hypnosis must involve a major neurophysiological alteration. Typically it is argued that specific bodily symptoms characterize hypnosis which the trained hypnotist can readily appreciate and identify. Furthermore, it is generally believed by these workers that unique neurological changes exist during the hypnosis that either already have been or would soon be demonstrated by rigorous research.This general view of hypnosis has been particularly popular among medically trained and biologically oriented individuals. The tradition is exemplified by Mesmer (1948), Braid (1960), Charcot (1882), to some extent Erickson (1939) and most recently Spiegel (1972).

An almost opposite response to hypnosis has been to argue that unique characteristics of hypnosis do not exist--the extreme version of this view holds that hypnosis reflects some kind of elaborate hoax. Early examples of this position are the writings of Hall (1845) in the mid-nineteenth century and those of Hart (1898) at the turn of the century. As rigorous investigators have been able to show that many of the claims concerning the effects of hypnosis have simply not stood up to close scrutiny, this position has found considerable support. Historically, Mesmer's animal magnetism, the Marquis de Puysegur's lucid somnambulism, and innumerable other more or less plausible claims about the effects of hypnosis have been questioned and discarded following careful studies. The work of investigators such as Young (1927, 1940), Pattie (1935, 1941) and Hull (1933) gradually delineated phenomena as quantitative methods were applied to the study. More recently Barber (1969) and Sarbin and Coe (1972) have forcefully expressed more extreme versions of the skeptical position.

Although it has been fashionable to argue that recent years have seen a gradual convergence of views, it is my belief that the manner in which one conceptualizes hypnosis and, perhaps even more important, the manner in which one operationnally defines it will help explain the empirical discrepancies in the observations of different investigators. I hope to show that it is not necessary to assume neurophysiological changes unique to hypnosis (for which no solid evidence as yet exists) in order to appreciate the utility and subjective reality of the hypnotic phenomenon. By the same token, it is difficult and perhaps impossible to design studies that can document the behavioural consequences of alterations in subjective experience from a point of view which essentially rejects the study of subjective experience as either a meaningful or, for that matter, attainable scientific goal. That which attracts our attention to hypnosis is the apparent change in subjective experience. While it is essential to find ways of demonstrating these changes in behavioural terms, it is also necessary to identify those behaviours which can reflect these changes. A definition of hypnosis will be discussed with the aim of facilitating rigorous systematic research without losing sight of the central characteristics of the phenomenon under investigation.

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THE DEFINITION OF HYPNOSIS

If we are to advance beyond the stage of arguing state versus hoax, it is essential for any systematic study of hypnosis to begin with a reasonable operational definition of the phenomenon. The two major ways in which hypnosis has been defined are 1) in terms of what is done to the subject, and 2) in terms of the subject's response.

Traditionally, hypnosis has been defined in much the same way as psychotherapy: an interaction that occurs when a trained individual, the hypnotist (psychotherapist), carries out what he calls hypnosis (psychotherapy). In other words, the qualifications of the hypnotist and the fact that he hypnotizes and asserts that the patient is hypnotized are the criteria. Unfortunately, the consensus within the field is by no means sufficient, and experts do not necessarily agree whether a given patient has in fact been hypnotized. While the inadequacies of such a loose definition seem evident, a variant of this approach has found considerable favor in the neo-behaviourist scientific community.

Most notably, Barber (1969) and his students have defined hypnosis by its antecedent events; in other words, hypnosis is that which occurs following a standardized induction procedure. Unfortunately, the response of unselected individuals to hypnotic induction procedures varies widely, depending upon their ability to respond. Typically, some 15% will be profoundly affected, some 5-10% will show hardly any response, and the remaining individuals will show varying levels of responsivity--the whole group more or less approximating the normal distribution.

Even more troublesome, moreover, is Bernheim’s classic observation that all hypnotic phenomena can be elicited in suitable individuals without any formal induction procedure. Clearly, if a hypnotic induction is unnecessary for some individuals and not sufficient to induce hypnosis for others, it cannot be used to define hypnosis. 1

The alternate approach recognizes that we are dealing with a phenomenon which cannot be identified by specific antecedent events, and for which no invariant psychological or physiological concomitants have been identified. Under these circumstances it seems reasonable to approach the identification of hypnosis as a problem analogous to the diagnosis of a state such as depression or sleep (without recourse to EEG).

In its simplest form one would define hypnosis as that state or condition which exists when appropriate suggestions will elicit hypnotic phenomena. Hypnotic phenomena are then defined as positive responses to test suggestions which on analysis all turn out to involve suggested distortions of perception or memory.

The construct of hypnosis as a subjective state in which distortions of perception or memory can be elicited by suggestion is operationalized in standardized scales of hypnotic susceptibility. The most useful have been the Stanford Scales (Weitzenhoffer and Hilgard 1959, 1962), which present a variety of hypnotic items to the subject and

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measure the individual response in a standardized fashion. Though it is necessary to specify responses in behavioural terms, it should be emphasized that the resulting scores validly reflect the hypnotic process only to the degree that the behaviour reflects alterations in the individual's subjective experience (Orne 1966). Fortunately, there is a high degree of concordance between what the subject independently describes as his experience and how he behaves in properly administered standardized tests. There are some circumstances, such as when a test is repeatedly administered with intervening treatments (as in studies designed to evaluate procedures proposing to increase hypnotizability) when the subject's objective behaviour may he affected more than his subjective experience. It seems crucial therefore that investigators keep in mind that objective scales are valid only to the degree that they continue accurately to reflect altered subjective events.

For reasons such as these, and because with relatively small samples it becomes very important not to increase error variance by including subjects who are less responsive that they appear to be, we have always felt the most appropriate criterion measure of hypnosis is a diagnostic session (Orne and O'Connell 1967) where an experienced clinician tries to induce a broad range of hypnotic phenomena in whatever fashion appears best suited to a particular subject. The response to hypnotic suggestion is evaluated behaviourally as well as by means of an extensive posthypnotic discussion which explores in detail the individual's experience. The diagnostic judgment is based on the congruence between the kinds of suggestions given, the behavioural response, and the subject's description of what he experienced. In many ways this procedure is an operationalized form of the traditional way of defining hypnosis by an experienced clinician's judgment based on extensive work with a particular subject. We have been able to achieve high levels of reliability between observers and routinely use two independent diagnostic sessions with two different investigators. Further, we do not view this type of evaluation as a substitute for at least two standardized tests of hypnotic responsivity. Rather the diagnostic sessions are intended to supplement standardized procedures by carefully establishing the concordance between the subject's description of what he experiences and the way he behaves.

In summary, I have tried to define hypnosis as that state or condition in which subjects are able to respond to appropriate suggestions with distortions of perception or memory. It should he clear that such a definition is descriptive rather than explanatory. Moreover, it may well be that the hypnotized subject may also carry out voluntary action because he is in hypnosis. Since we have found no actions which subjects would not carryout when requested to do so in the waking state (Orne 1970), simple behavioural compliance cannot he used to identify hypnosis. While it would appear that not all individuals have the capacity to respond to hypnotic suggestions, those individuals who do have this ability vary in their responsiveness to suggestion depending on the circumstances.

The basic questions which need to be resolved are the differences between those individuals who have the skill to enter hypnosis and those who do not, the circumstances which facilitate and/or inhibit the tendency to respond to hypnotic suggestion in those individuals who have the ability to do so, and the consequences of being in

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hypnosis for an individual’s psychobiological functioning.

One final point: In phrasing the definition I have sought to be as theoretically neutral as possible. It is appropriate to translate this definition into another conceptual framework. Thus, it is entirely compatible with my view to describe hypnosis as Sarbin (1950) does: a role which is played with such conviction as to become totally compelling to the individual. It would be essential for the individual to experience the role as real and not to be consciously acting a part. The role metaphor, if used in such a fashion, is operationally indistinguishable from my formulation. Equally acceptable and, in my view, operationally indistinguishable, is to describe hypnosis as a 'believed-in imagining' (Sarbin and Coe 1972). The crucial point in such a formulation is that the individual for the time being becomes unable to distinguish between his fantasy and other life experiences.

THE REALITY OF HYPNOSIS

Whether hypnosis is 'real' or a hoax is a question that has been raised ever since hypnotic phenomena were first described. The main reason why this issue remains with us today is, in my view, largely related to the tendency to confuse several different questions that are in fact subsumed by this deceptively simple problem.

There are four distinct major issues around which at one time or another controversy about the reality of hypnosis has revolved: 1) Is the mechanism which a given investigator has postulated to explain the phenomenology of hypnosis valid, e.g., is there such a thing as animal magnetism? 2) Does a formal hypnotic induction procedure bring about unique changes different from those seen without hypnotic induction, e.g., the paradigm followed by Barber and his students? 3) Can hypnotic suggestion lead to the transcendence of normal volitional capacity. e.g., in hypnotic age regression, do the thought processes come to resemble those of a child? Is an individual able to remember accurately what happened during childhood? 4) Does the hypnotized individual experience what he appears to experience? Does his behaviour reflect his phenomenal awareness, e.g., when hypnotic analgesia is induced and a pain stimulus administered, does the subject who asserts that he is comfortable nonetheless feel the pain?

While these four sets of issues do not necessarily exhaust what has been implied by the question of whether hypnosis is real, they may be sufficient to illustrate the range of issues involved. Such an analysis may help explain both how and why investigators have often talked past each other though they seem to be addressing the identical quest ion--the reality of hypnosis.

THE MECHANISMS BY WHICH HYPNOSIS IS EXPLAINED

Explanatory mechanisms inevitably seem to become an integral part of an investigator's way of thinking about the phenomenon. Particularly because the dramatic effects of hypnosis do not appear justified by equally dramatic causes, investigators have tended to postulate some new kind of psychobiological explanatory mechanism.

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The controversy about hypnosis would then focus on the validity of the particular explanatory principle that has been postulated.

Already in Mesmer's day disputes surrounded his work which illustrate this process. Mesmer sought to explain the cures following his treatment as the effects of an invisible fluid or force--animal magnetism. The Royal Commission appointed to investigate the claims of the Mesmerists initially agreed to study the results of treatment ,and members of the commission appeared impressed with some of the observed results. The inquiry soon shifted its focus to the question of whether the magnetic fluid which the Mesmerists had postulated actually existed. Although the commission acknowledged that some patients seemed to he helped by the Mesmerists' procedure, it was felt that such cures could best be explained as the consequences of 'mere' imagination. Because the experiments failed to provide evidence for a magnetic fluid, Mesmer’s claims were rejected and the phenomenon dismissed as not real.

A similar controversy was basic to the famous dispute between the schools of Nancy and Salpetiere (Chapter 1). The distinguished neurologist, Charcot, described what he believed to be invariant stages reflecting basic neurological changes associated with hypnosis. Bernheim rejected this position, and insisted that the effects of hypnosis were the product of suggestion. Further, he showed that it was not necessary to induce hypnosis formally for a responsive subject to manifest all hypnotic effects: suggestion alone could be sufficient. To Charcot's followers, the acceptance of Bernheim's view was tantamount to denying the reality of hypnosis ….hypnosis could be explained away as 'mere' suggestion. Again, what appeared to many to be a controversy concerning the reality of hypnosis was quite clearly a dispute about the mechanisms which produce it. Indeed, Bernheim, who was essentially accused of denying the reality of hypnosis, made the practice of hypnotherapy his life's work.

Similar issues persist to the present day. Whenever a new explanatory principle is evoked to account for hypnosis, there is a tendency to argue that hypnosis is not real if experimental work fails to document the postulated mechanism. Ultimately, we will, of course, need to understand how it becomes possible for some individuals to distort their experiences so dramatically. Without a meaningful theory the phenomenon continues to elude scientific clarification. By the same token, however, the absence of a satisfactory theory to account for the phenomena of hypnosis does not explain them away. Evidence that a given mechanism postulated to explain hypnotic phenomena fails to do so speaks to the inadequacy of a particular theory but tells us nothing about the reality of those events which the theory had unsuccessfully tried to explain.

Does a formal hypnotic induction procedure result in unique changes?

Whether unique effects of hypnotic induction can be demonstrated with unselected individuals is by no means established. From the perspective of this discussion, even more troublesome is the tendency to confuse that question with questions about the reality of hypnosis. Since the early 1960s, Barber (1969) and his students systematically tried to study hypnosis by comparing individuals exposed to an induction procedure with individuals who are treated in a different fashion. Typically, few if any differen-

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ces emerge when unselected subjects exposed to hypnotic induction are compared with unselected subjects exposed to a task-motivated condition, fantasy instructions, and the like. As I have pointed out earlier, such a design appears to address the reality of hypnosis only if hypnosis is defined exclusively by its antecedent events. Such a definition fails to take into account the nature of the phenomenon under investigation. Furthermore, the task-motivated instructions are likely to produce effects which mimic the behaviour of hypnotized individuals without necessarily bringing about a change in the individual's subjective experience. On the other hand, some types of fantasy instructions are more likely to produce the same phenomenon as other kinds of hypnotic induction procedures.

Though one might argue, as Barber has, that the absence of dramatic differences between hypnotic induction groups and control groups given different types of instructions challenges the utility of the construct of hypnosis, such a position fails to account for the dramatic changes in subjective experience that seem to be brought about in some individuals following a variety of different antecedent events. It is the occurrence of a sequence of events such as we described at the beginning of this paper which needs to be understood: the demonstration that it does not depend upon formal induction procedures speaks to that issue but does not address the reality of the phenomenon that is observed.

Transcendence of normal volitional capacities and the correspondence of subjective experience and verbal report

Whether hypnosis can lead to the transcendence of normal volitional capacity and whether the hypnotized individual actually experiences what his behaviour and his verbal reports seem to indicate are the kinds of questions about the reality of hypnosis which concern the nonspecialist when he asks whether hypnosis is real. These two questions are conceptually distinct. It is possible that the answer to one of these is affirmative and to the other negative. An empirical resolution of these questions would seem essential for the development of any definitive theory to account for hypnotic phenomena. It is these issues which the bulk of our research has tried to address. How these problems are formulated and translated into operational definitions will, however, depend in a large part on how hypnosis has been defined.

The discussion to follow will strive to clarify some of the problems of research in this area: why we have developed some special methodological tools to deal with them and selected findings which, in my view, document the subjective reality of hypnosis and may help lay to rest the concern about this problem which has perhaps inadvertently been encouraged by some of our observations about hypnosis in recent years.

SOME METHODOLOGICAL CONSIDERATIONS

In his major monograph on hypnosis and suggestibility, Hull (1933) set the standard for modern research in this field. Because it was tedious to identify highly responsive hypnotic subjects, he favored an experimental design which compared the responses

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of an individual while hypnotized with his own responses in a waking state. Hull carefully counterbalanced the order or presentation in an effort to control for order effects. However, he himself already recognized some of the serious difficulties potentially inherent in such a design, particularly that it was possible for a subject to depress his waking performance in order to enhance the relative level of the hypnotic performance.

This difficulty, as well as the problem of treating subjects in the same way whether they are hypnotized or awake, and the likelihood of unwittingly biasing the subject's response by the manner in which some instructions are given, and finally (from my point of view particularly important) the extent to which a within-subject design can communicate what is expected--or wanted--of the subject's performance, convinced me that additional controls were required (Orne 1973). I rejected an independent group design, 2 partly because of the extreme cost involved in finding highly responsive subjects and also because an independent group design does not solve the problem of experimenter bias. In observing other investigators, I had noticed that hardly anyone gave instructions to hypnotized individuals in the same manner as to waking subjects, a tendency that I found difficult if not impossible to eliminate when I ran subjects myself. To deal with these issues, a special simulator comparison group was developed.

Elsewhere (Orne 1971) I have described in detail the merits and demerits of using unhypnotizable subjects instructed to simulate hypnosis as a comparison group. The logic of the design is based on that developed by Hull, using highly responsive subjects as their own controls, in hypnosis and in the waking state. The simulating subjects who are run in exactly the same fashion as deeply hypnotized subjects serve to establish whether motivated unhypnotized subjects could figure out the responses that are desired from the totality of cues available to them--including prior information, the experimental procedure, and subtle (perhaps unwitting) cues from the experimenter. Simulators are not intended to be true controls to be compared directly with hypotized individuals. Rather they indicate whether an unhypnotized subject could successfully mimic the behaviour of the hypnotized individual for an investigator-hypnotist who is blind to their true status. The model demands that unhypnotizable subjects be used as simulators since it is the only way to assure that these subjects will not enter hypnosis. (Obviously we confound hypnotizability as a trait with the presence of hypnosis as a state. 3 )

3 If there are no differences between real and simulating subjects, it becomes impossible to determine whether this is due to the selection of inappropriate dependent variables or whether it is because there are no differences between these groups. In any case, a lack of differences indicates that a particular experimental procedure is inadequate to establish a particular effect. The fact that

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It should be emphasized that simulating subjects must not receive any special training on how to simulate and they must be aware that the hypnotist does not know their true status and be convinced that he will terminate the experiment if he comes to believe they are faking. The hypnotist, by the same token, must in fact be unaware of the subject's true status. As I have reported, it is not possible for experienced hypnotists to distinguish between these two groups of subjects during a simple induction procedure and without special tests or extensive contact. In practice, the hypnotist is also required to guess the status of the subject which provides further assurance concerning possible differential treatment of these two groups by the hypnotist.

This design provides the opportunity for a rigorous test on the myriad of assertions concerning changes that are unique to hypnosis, concerning abilities that are presumably unique to hypnotized individuals, and concerning what the subject might or might not figure out from the experimental procedure concerning the desires of the hypnotist which are not explicitly suggested to him.4

An example from hypnotic age regression

A hypnotic phenomenon of both theoretical and practical importance is hypnotic age regression. In an early study (Orne 1951), a highly responsive subject was given appropriate suggestions to regress to age six. accordingly, he began acting like a child, talking like a child and apparently thinking like a child. After he had completed some drawing in regression, I asked him to put his name at the bottom of the drawing, which he did in typical childlike printing. On a hunch, I then asked him to continue to write and dictated, 'I am conducting an experiment which will assess my psychological capacities.' He printed slowly and laboriously but with perfect spelling. It struck me that such an obvious discrepancy may be the cause of much controversy about hypnosis. Not only does it negate the view that age regression involves a return to intellectual functioning of early childhood, but it would be quite wrong to believe with the skeptic that such data shows age regression to be a fraud. If it were really a fraud, if the subject were merely seeking to put one over on the hypnotist, would he be so stupid as to write such a sentence without spelling errors? This subject's behaviour can therefore be taken as an indication that we are not dealing with mere conscious

unhypnotizable subjects are used in the comparison group is irrelevant in the case of null findings. If, however, differences are noted, they cannot be explained as a function of differential treatment by the hypnotist-experimenter, but they may be related to differences in hypnotizability as a trait, or to the presence of hypnosis in the experimental group or to the effect of instructions to simulate in the comparison group. To distinguish definitively between these possible alternatives, additional experimental data are needed.

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role playing and that, at the very least, the hypnotized individual's judgment is affected. Although I view this argument as plausible and correct, you may not choose to agree with me. It is precisely to evaluate the likelihood of such an event that the simulator design was developed.

The subtlety of the problem is illustrated in a later study of hypnotic age regression. Reiff and Scheerer (1959) in a major monograph had compared the behaviour of individuals age regressed to ages 10, 7, and 4, with role players instructed to role play ages 10, 7 and 4, respectively, using a variety of Piaget-type tasks and other behavioural items. One somewhat different test was devised by the investigators. Subjects regressed to age four, playing in a sandbox, were asked by the experimenter whether they wanted a lollipop. All subjects responded affirmatively: the examiner then removed the wrapper and handed to each regressed subject, whose hands were covered with mud, a lollipop, while holding it by the stick in such a way as to make it awkward for the subject to reach for the stick. Hypnotized subjects were satisfied to take the eating end of the lollipop into their dirty hands and put it into their mouths. Role players, however, awkwardly reached around the stick and would not put their hands on the part that was to go into their mouths.

On replication, using simulating subjects where the hypnotist was blind to their true nature, both reals and simulators took the lollipop at its eating end with their dirty fingers. This aspect of the study clearly indicates something about the cues the hypnotist puts into the situation. Lest one make an inappropriate inference, we also examined what 4-year-olds did under these circumstances. To our surprise, none of the 4-year-olds was willing to take the lollipop by its eating end: all sensibly insisted on taking it by the stick (O'Connell et al. 1970)!

Other issues of transcendence of normal volitional capacities

Though it appears that when the hypnotized subject's performance in hypnosis is compared with his performance in the waking state he is able to transcend his normal abilities to a considerable degree, this observation must be qualified by evaluating what highly motivated waking subjects can be induced to do. For example, it was possible to show that by motivating subjects in the waking state they could be induced to exceed their previous hypnotic performance on an endurance task (Orne 1959). Simulating subjects can serve as an independent control group to study this kind of question (Orne 1959; Damaser et al. 1963; Shor 1964; Orne and Evans 1965). To answer transcendence questions, task-motivated groups (Barber 1969) are equally appropriate controls. Summarizing the work on the transcendence of normal volitional capacities, all of the claims concerning significant changes due to hypnosis can be mimicked by highly motivated individuals in well controlled studies.

We would, however, be loath to conclude that hypnosis would not result in increased performance on some of the many dependent variables that have not yet been rigorously studied. For example, I find it difficult to believe that simulating subjects would calmly tolerate major surgery without benefit of anaesthesia, though we have long since learned to be cautious about even such improbable possibilities. At the

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present time we can only suggest that any claims for abilities unique to hypnosis require careful validation using the real-simulator model.

HYPNOTIC PHENOMENA THAT CANNOT BE EXPLAINED AS VOLITIONAL ROLE PLAYING

As has been suggested earlier, the question which ultimately bothers the observer of hypnosis is whether the subject's behaviour truly reflects what he experiences. Does the hand that rises really feel light? As he struggles to separate his hands in a handclasp, does he really feel unable to take them apart? When he seems to have forgotten what has happened, is he really unable to recall?

These questions, of such interest to the naive observer, also seem to me central to the study of hypnosis, though they are unfortunately hardly considered in many of the neo-behaviourist studies of hypnosis, probably because of the admittedly difficult problem of operationalizing subjective experience. Similarly, role theory (Sarbin 1950) as it addresses hypnosis has provided for the possibility of role playing on a nonconscious level which would make hypnosis real in the limited sense that it has been discussed here. By the same token, role theory (Sarbin and Coe 1972) tends also to speak of playing a role in a conscious sense, sliding from one position to the other with little difficulty and without an apparent need to draw a distinction between them. Conscious role playing would be the same as spontaneously simulating hypnosis. It is hardly surprising therefore that an investigator who intentionally uses simulating subjects as a comparison group to clarify the behaviour of the hypnotized individual would regard the distinction between conscious and nonconscious role playing as central to his understanding.5

Perhaps the best clinical evidence for the subjective reality of hypnotic effects derives from the treatment of chronic pain and the use of hypnosis as an anaesthetic. Though environmental contingencies certainly affect the expression of pain, the repeated choice of hypnosis as an analgesic when alternatives are readily available is difficult to explain without assuming that the anaesthesia suggestions effectively alter the individual's experience (see Hilgard and Hilgard 1975).

Real simulator studies are perhaps most relevant in this context. The ones which are particularly interesting are those that are counterexpectational: that is, where the simulating subject is unable to predict accurately what the deeply hypnotized individual will do--resulting in a difference between these groups that may be ascribed to hypnosis, to the presence of hypnosis, or to being hypnotizable, but not likely to be a function of simulation as an independent treatment. An example of this kind is the spontaneous occurrence of evidence of trance logic which does not occur with all subjects but often will be seen in deeply hypnotized individuals.

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For instance, when a subject, who is able to do so, is given the suggestion to hallucinate a person sitting in a chair and is asked to describe what he sees, he may say, 'I can see him . . . he is there. . . But it is strange, I can also see the outline of the chair through him.' While this response occurs spontaneously in only 25-30% of deeply hypnotized individuals who are able to hallucinate a person, I know of no instance where a simulator has spontaneously6 reported seeing the chair through the hallucinated person. The mixing of hallucination and perception seems to occur spontaneously only with those subjects who are deeply hypnotized. This finding has been corroborated in two independent experiments which have explored it (Peters 1973; MacDonald and Smith 1975).

A related kind of phenomenon is source amnesia, studied by Evans (1965) and Evans and Thorn (1966). Here a subject in deep hypnosis is asked a number of questions including some such as 'An amethyst is a blue or purple gem stone: what color does it turn when it's heated?' Almost no one is familiar with the answer, and when the subject in deep hypnosis says he doesn't know, the experimenter casually answers yellow and then goes on to the next item. He then induces amnesia and awakens the subject. When asked what transpired, the subject insists that he cannot remember. The subject is then given a simple test of information which includes the amethyst item: when asked what color it turns when it's heated, he responds 'Yellow' in an almost automatic fashion. If then asked how he knows this, he may offer some plausible possibility such as learning the information in a geology class. In short, the subject (who is no longer in hypnosis) displays no knowledge of the true source of his information. Hence the term 'source amnesia.'

Clearly, such a response indicates that the item of information exists in the subject's memory storage. It would be incorrect, however, to therefore assume that the subject's amnesia is not real. Amnesia is a descriptive term indicating a subject's inability to recall a particular set of events. It speaks to a problem of retrieval which can be solved if the information is addressed in a different manner, just as someone unable to recall a name may have little trouble recognizing it among a list of names. It would seem that no one shamming amnesia would be so naive as to admit knowledge that he acquired during a time for which he is supposed to have amnesia. In this instance, however, you need not accept my opinion. Hard data is available!

In a study (Evans 1971) using reals and simulators, approximately one-third of the deeply hypnotized subjects showed source amnesia while not a single simulator ever admitted having known the answer to questions he learned during hypnosis.

In another study where we investigated what happened if the hypnotist disappeared, we found that when the study was carefully carried out, simulating subjects typically stopped simulating when they were left alone (Evans and Orne 1971). They had lost

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the audience for the role they were required to play. Deeply hypnotized individuals continued in trance for some minutes, only gradually arousing themselves over time--suggesting a state or, in Sarbin's metaphor, the synonym, a high level of organismic role enactment (Sarbin 1950).

In another study, we tested the effect of a posthypnotic suggestion that the subject run his hand over his hair whenever he heard the word EXPERIMENT: this test took place outside of the experimental context in a situation where the hypnotist would neither know nor care about the subject's response. Under these circumstances, simulating subjects did not respond, while those who had been deeply hypnotized were as likely to respond in the absence of the hypnotist as in his presence. Simulators, moreover, actually responded more frequently in the hypnotist's presence than deeply hypnotized subjects who occasionally failed to hear the posthypnotic cue when it was well embedded in a sentence, something that very rarely occurred with simulators (Orne et al. 1968).

Building upon his observation that deeply hypnotized subjects ceased to respond to the word EXPERIMENT when they were given the instruction, 'When I count to three, you will no longer run your hand over your hair every time you hear the word EXPERIMENT'--even though the hypnotist had yet count to three--Sheehan (1971) carried out a series of studies which manipulated pre experimental expectancies. When subjects were given the expectation that a hypnotically induced automatic response persisted until a specific cue was given lifting the suggestion, simulators tended to behave in accordance with these expectations. Deeply hypnotized individuals still tended to discontinue their automatic behavior once it was clear to them that a suggestion was about to be terminated. These observations would seem to support the view that the deeply hypnotized individual is highly attuned to the hypnotist's explicit and implicit wishes which come to determine his experience, whereas the simulator is more influenced by prior knowledge and expectations.

Perhaps the most exciting finding is the recent work of Evans and Kihlstrom (1973) and Kihlstrom and Evans (1976), which investigated the effect of suggesting posthypnotic amnesia on the order of recall. These studies did not involve simulators: rather they studied an unsuggested consequence of suggested hypnotic amnesia, where an unobtrusive measure in the sense of Webb et al. (1966) was used. It was shown that in response to amnesia suggestions those individuals who were hypnotized but nonetheless had some recall remembered those items they did recall in a random order. On the other hand, less hypnotizable individuals who remembered the same number of items were likely to recall them in the order in which they had occurred. This novel observation appears to reflect a robust phenomenon which is not destroyed either by exhorting subjects to remember, providing them with honesty instructions, or even asking them to put the material in a correct temporal sequence (Kihlstrom 1975). The disorganization of recall is thus an unsuggested consequence of a suggestion to have amnesia. It is not seen, regardless of the level of the hypnotic response, unless amnesia is specifically suggested. Particularly interesting is the recent study by Spanos and Bodorik (1977) which replicates the finding of disorganized recall in hypnotized subjects, but fails to find this effect in individuals given task-motivated instructions.

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CONCLUSIONS

As I have tried to point out, controversies about the very existence of hypnosis have persisted since the phenomenon was first described. Over the past 25 years, however, we have witnessed an unprecedented amount of research on hypnosis which has been accompanied by a distinct shift in the way hypnosis is perceived. Prior to the time, there had been a developing consensus that hypnosis was effective in bringing about certain types of therapeutic changes (Wolberg 1948) and was a powerful technique in controlling human behaviour ( Estabrooks 1943), that it made possible unusual feats of strength (Hull 1933), unusual feats of menory (Erickson 1943), and unusual types of control over an individual's biological processes (Dunbar 1943). Though acknowledged to be a powerful phenomenon, it was rarely integrated into general textbooks of psychology and received scant systematic attention even in psychiatry. Little systematic effort was made to understand hypnotic phenomena within the broader framework of psychobiological principles.

Ensuing work led to the development of novel and more appropriate methodological approaches which challenged some of the widely believed and apparently well established evidence (Hull 1933) that hypnosis led to the transcendence of normal volitional capacities. As this evidence became disseminated, it was inappropriately used to argue that hypnosis was not real. In such a context my demonstration that even highly trained clinicians were unable to identify hypnotized individuals from simulators in a single session contributed to the overall confusion.

It took a surprising amount of work to document what I had been careful to explain in the first publication on the use if simulators in research (Orne 1959)-- that despite the superficial similarity of the hypnotized individual's behaviour, the underlying mechanisms are by no means identical. We have now shown with careful, detailed studies systematic differences that are likely to be a function of the hypnotizable individual's being hypnotized. Some of these differences help clarify the nature of the hypnotic phenomenon. Perhaps equally important, they help to document that the hypnotized individual's behavior cannot be explained as a conscious effort to please the hypnotizer or as some form of conscious role playing.

Whether the hypnotized individual is characterized as responding to a world created by the hypnotist's words while disregarding many of the circumstances of the real world, or whether the hypnotized subject is characterized as deluded (Sutcliffe 1958) or as engaged in a form of role enactment (Sarbin 1950), or responding to a believed-in imagining (Sarbin and Coe 1972) does not matter. Regardless of how we describe hypnosis, it is real in the sense that the subject believes in his experience and is not merely acting as if he did. To say that an individual regressed to age four believes that he is four does not, however, mean that he therefore knows only what he knew when he was four and is really like a child. To some degree we may indeed see an increase in accurate recall of events that once transpired: to some extent hypnosis will also facilitate the creation of pseudo-memories. Indeed, perhaps the most striking characteristic which we have noted about hypnotized individuals--in contrast to simulators--is their remarkable willingness to mix the experiences in the world suggested

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by the hypnotist with the percepts of the real world, often in a remarkably uncritical fashion.

Having obtained evidence for the subjective reality of the hypnotic phenomenon and at the same time evidence that hypnosis does not result in physiologically real color blindness, uniocular blindness, uniaural deafness, or what you will, we remain confronted with the puzzle of how some individuals can for a time distort their perception or memories. It is merely a curious quirk of the mind which can be seen under some circumstances or does it reflect important processes which can have profound consequences, both therapeutically and for an understanding of human mental functions? While I am firmly convinced the latter is true, much work needs to be done to characterize the difference between the effect of merely having a fantasy as opposed to the effect of having a fantasy and for a time accepting it as real.

Having documented substantial differences between simulating and real subjects, it is also necessary to recognize, as Bowers (1976) has aptly emphasized, that the simulating model is not suited to exploring the effects of suggestions which are widely recognized and known within the subject population 7. For example, the tendency of the hypnotized individual to become relaxed and initially to speak in a low, somewhat colorless voice is sufficiently well known that it is inevitably mimicked by all simulators. This should not he taken to mean, however, that these characteristics are therefore not typical of hypnotized individuals. The important systematic studies of pain and its suppression by hypnosis carried out by Hilgard and Hilgard (1975) present lawful information about pain, even though simulating subjects can mimic most of these changes. Fortunately, experimental subjects are on the whole honest, and it is neither feasible nor necessary to set up byzantine procedures in each instance to test the validity of subjective reports. Obviously such reports have problems, many of which are closely analogous to those of psychophysics. While psychophysics has had to concern itself with questions of response set and other kinds of bias, it has appropriately not worried about purposive simulation.

Though studies using simulators and other related forms of comparison groups will continue to he needed to test some particular questions or striking claims not otherwise easily resolved, it is my hope that the need for such elaborate procedures will diminish as we rethink our search for psychological or physiological correlates that are unique to hypnosis. It seems likely that it will be more productive to focus on identifying basic cognitive, social psychological, and neurophysiological mechanisms that link hypnosis with other psychobiological processes..

An example of this kind follows from the work of Shor (1960), Shor et al. (1962), As (1963), and Tellegen and Atkinson (1974) which has shown that an individual’s

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tendency to have naturally occurring trance-like experiences or the ability of absorption-- which appears to be an underlying mechanism for the occurrence of such events--relates to the ability to enter hypnosis. This process involves an individual's increased ability to become absorbed either in his own thoughts or by some particular feature of the external environment in a manner which causes him to exclude other external stimuli which would normally capture his attention. The ability to focus attention has long been acknowledged as important to the ability to enter hypnosis. However, one would hardly expect the ability to focus attention to be a unique attribute of hypnotizable individuals. Nonetheless, the psychobiological processes reflecting such deployment of attention have been the subject of considerable study in other contexts and may well provide some important empirical links between hypnosis and other related phenomena. For these reasons, we are currently examining such basic mechanisms as habituation, the orienting response, and measures of cognitive effort as means for empirically assessing the deployment of attention.

Our hope is to establish links between hypnosis and other phenomena rather than search for any unique psychobiological correlate of hypnosis. In such an effort we have little concern about whether a particular process can be mimicked and even less about whether the process is unique to hypnosis. Rather, we are seeking to identify a variety of mechanisms associated with hypnosis which may begin to provide an understanding of how hypnosis relates to other circumstances which involve the focussing of attention and the ability to choose for a time to ignore significant aspects of the real world. It is our hope that as such an understanding evolves we will ultimately be able to understand how in hypnosis it is possible to gain control over the subject's information input, how the mechanism of recall can be affected, and the consequences of such events for the individual's total psychobiological functioning.

ACKNOWLEDGEMENTS

The author would like to thank Frederick J. Evans, A. Gordon Hammer, Emily Carota Orne, William M. Waid and Stuart K. Wilson for their substantive comments during the preparation of this paper.

The substantive research upon which the theoretical outlook presented in this paper is based was supported in part by grant MH 19156 from the National Institute of Mental Health and by a grant from the Institute for Experimental Psychiatry.

This manuscript closely follows a paper presented at the New York Academy of Sciences which was published in 1977 in the Annals of the New York Academy of Sciences, 296, 14-33.

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