Orne, M.T. The construct of hypnosis: Implications of the definition for research and practice. Annals of the New York Academy of Sciences, 1977, 296, 14-33.


Martin T. Orne

The Institute of Pennsylvania Hospital and University of Pennsylvania

Philadelphia, Pennsylvania 19139

Although hypnotic phenomena have been well delineated since the Marquis de Puységur's historic description, controversy persists concerning the nature of hypnosis and even its very existence. It is my hope that, in this paper, by asking what it is that makes hypnosis interesting -- to some, even implausible -- and exploring how the phenomena have been defined, it will be possible to lay to rest some disagreements about hypnosis. In particular, I will seek to address issues about the reality of hypnosis that are in fact controversies about the mechanisms responsible for what is observed. Such an effort is intended to clarify definitional issues and distinguish between those questions which require empirical as opposed to those which demand conceptual clarification.


Consider for a moment what occurs with a responsive subject following a simple hypnotic induction 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 has occurred. However, during his conversation, I twice remove my eyeglasses and each time he smoothes 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 has 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

* The substantive research upon which the theoretical outlook presented in this paper is based was supported in part by grant MH 19156-06 from the National Institute of Mental Health and by a grant from the Institute for Experimental Psychiatry.



15 Orne: The Construct of Hypnosis

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 Failure of Behavioral Compliance to Index Hypnosis

It is not the trivial items of behavior that cause us to call this set of events hypnosis but rather an inference about the subjective events reflected in these behaviors. The subject was not instructed to raise his hand slowly; rather he had been told that 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 about 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 behavior had reflected changes in the individual's subjective experience. In other words, it is not the overt behavioral compliance that is elicited by the hypnotist which distinguishes the phenomenon. Thus, the drill sergeant can and does elicit behaviors involving greater efforts, a higher degree of compliance, and extending over a longer period than do most hypnotic suggestions. Although some might focus on the vague resemblance to hypnosis with regard to the automaticity of behavior in both situations, the soldier's actions seem to involve quite different, processes.

These differences are important for an appreciation of what makes hypnosis unique. In the case of the drill sergeant, the social context defines his authority over the soldier. Elaborate, formal and informal sanctions exist to compel obedience to the sergeant's orders. Finally, these orders invariably demand behaviors that -- though requiring effort -- the soldier can carry out if he chooses to do so. Contrast this with the hypnotic situation. Hypnotist and subject may be strangers, but beyond the agreement to participate in hypnosis (and the absence of a hostile relationship), social sanctions which would compel compliance on the part of the subject are not required. Given a minimum of cooperation, the subject's hypnotizability -- a reasonably enduring trait -- seems to be the single most important determinant of the subject's response.1

Even though the hypnotized subject may respond to the suggestions of the hypnotist in an apparently automatic fashion, there is no compelling evidence that hypnotized individuals will do things in hypnosis that they are not prepared to do in the same social context without hypnosis. Thus, hypnosis is never induced in a vacuum and generally occurs in one of three settings: (1) in a therapeutic context, (2) in an experimental context, and (3) in the context of a demonstration with a volunteer subject. In all three settings the range of


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behavior which an individual will carry out if requested to do so is vastly greater than is generally believed. This willingness to comply is such that it has been difficult to document any increment of control following the induction of hypnosis over and above that already present prior to hypnosis.

Some time ago I summarized the evidence 2 that, contrary to my own early views,3 the hypnotizable individual is not more motivated than the unhypnotizable individual to comply with the requests of the hypnotist that do not involve hypnotic phenomena. In this I was particularly impressed with the striking and oft-ignored observations originally made by London and Fuhrer4 that unhypnotizable subjects are more willing to exert themselves in feats of endurance prior to hypnosis or following the induction of hypnosis than hypnotizable individuals. A similar tendency was reflected in a higher pain threshold of unhypnotizable subjects prior to an experiment.5 Again, using punctuality as the measure of motivation, as is often done in a therapeutic setting, one finds that highly hypnotizable individuals are more likely to arrive late or even miss appointments than those subjects who have more difficulty in entering hypnosis.6

It is only when hypnotic phenomena are suggested that the apparent increase in compliance of the hypnotized subject becomes evident. Thus, the hypnotizable individual will not hold a kilogram weight longer than his unhypnotizable counterpart, 3 but his arm soon begins to float upward when suggestions of lightness are given, and while he may promptly forget what has transpired when suggestions of amnesia are given, unhypnotizable individuals exposed to the same suggestions fail to respond.

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, however, the induction of hypnosis does not require an intense interpersonal relationship or 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 strikes me that it is the paradox between the apparently trivial induction procedure and the apparently dramatic consequences that is responsible for many of the difficulties which have surrounded hypnosis since its discovery.


The reactions to hypnosis that seem to evolve among both serious lay observers and scientists seeking to understand hypnosis appear to polarize into one of two major categories (see Sutcliffe's distinction between "credulous" and


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"skeptical" views 7). One group seems convinced that hypnosis is a uniquely powerful state that 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 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 desires. 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, which the trained hypnotist can readily appreciate and identify, characterize hypnosis. Furthermore, it is generally believed by these workers that unique neurological changes exist during hypnosis that either already have 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,8 Braid,9 Charcot,l0 to some extent by Erickson,11 and, most recently, by Spiegel.12

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 C. R. Hall 13 in the middle of the nineteenth century and those of E. Hart 14 at the turn of the century. Because 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 Puységur'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 P. C. Young,15,16 Pattie,17, 18 and Hull 19 gradually delineated hypnotic phenomena, as quantitative methods were applied to the study. More recently, Barber 20 and Sarbin and Coe 21 have forcefully expressed more extreme versions of the skeptical position.

In the context of a conference such as the one on which this volume is based, one often tends to minimize differences between positions and point to the gradual convergence of views taking place in the last few years. Undoubtedly, to some extent there has been a convergence of views; however, the way in which one conceptualizes the phenomenon and, even more importantly, the way one operationally defines it, will have profound consequences for the manner in which it is empirically studied and for the kinds of conclusions that follow from such studies. 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 potential utility and subjective reality of hypnotic phenomena. By the same token, it is very difficult and perhaps impossible to design studies that can document the behavioral consequences of alterations in subjective experience from a position which basically rejects the study of subjective experience as an 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 behavioral terms, it is necessary to identify those behaviors which


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reflect these changes. From this point of view, a definition of hypnosis will be discussed to facilitate rigorous, systematic research while taking into account the central characteristics of the phenomenon under investigation.


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 is (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 (or psychotherapist), carries out what he calls hypnosis (or psychotherapy), respectively. 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 neobehaviorist scientific community.

Most notably, Barber 20 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 -- with 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.†

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 isolated. 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

† It is worth noting that an induction procedure defines the hypnotic context for all subjects, regardless of whether they are hypnotized. This change in context can bring about significant alterations in the interpersonal relationship that, in the therapeutic situation at least, may have profound consequences for behavior. Such consequences may be unrelated to the presence of hypnosis but follow solely from the hypnotic context.


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which on analysis all turn out to involve suggested alterations of perception or memory.

The construct of hypnosis as a subjective state in which alterations of perception or memory can be elicited by suggestion is operationalized in standardized scales of hypnotic susceptibility of which the Stanford Scales22,23 have been the most useful. These scales present a variety of hypnotic items to the subject and measure the individual response in a standardized fashion. Though it is necessary to specify responses in behavioral terms, it should be emphasized that the resulting scores validly reflect the hypnotic process only to the degree that the behavior reflects alterations in the individual's subjective experience.2 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, however, 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 behavior may be affected more than his subjective experience. It therefore seems crucial that investigators keep in mind that objective scales are valid only to the degree that they continue to accurately 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 than they appear to be, we have always felt the most appropriate criterion measure of hypnosis is a diagnostic session 24 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 behaviorally 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 kind of suggestions given, the behavioral response, and the subject's description of what he experienced. In many ways this procedure is a rigorously 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 the careful establishment of the concordance between the subject's description of what he experiences and how 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 be clear that such a definition is descriptive rather than explanatory. Moreover, it may well be that the hypnotized subject carries out a suggested action also because he is in hypnosis; however, since we have found no actions which subjects would not carry out when requested to do so in the waking state,25 simple behavioral compliance cannot be used to identify hypnosis. Although 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.


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those individuals who have the skill of entering hypnosis and those who do not; the circumstances that facilitate and/or respectively inhibit the tendency to respond to hypnotic suggestion in those individuals who have the ability to do so; and the consequences of being in 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, however, to translate this definition into another conceptual framework. Thus, it is entirely compatible with my view to describe hypnosis, as Sarbin 26 does: a role that is played with such conviction as to become totally compelling to the individual. It would be crucial, however, that the individual experience the role as real, rather than that he is 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." 21 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.


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 the several different questions that are in fact subsumed under 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 behavior 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 that are involved. Hopefully, such an analysis will help explain both how and why investigators have often talked past each other, even though they seem to be addressing the identical question, 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


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

Already in Mesmer's time, the disputes surrounding his work 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. However, the inquiry soon shifted its focus to the question of whether the magnetic fluid the Mesmerists had postulated actually existed. Although the commission acknowledged that many patients seemed to be 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 was dismissed as not real.

A similar controversy was basic to the famous dispute between the schools of Nancy and Salpêtrière. 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 formal induction of hypnosis was not necessary in order 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 that produce it. Indeed, Bernheim, who was presumably 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 experience 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 explain 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 for which the theory has unsuccessfully tried to account.

Does a Formal Hypnotic Induction Procedure Result in Unique Changes?

Whether with unselected individuals unique effects of hypnotic induction can be demonstrated is by no means established. From the perspective of this discussion, however, even more troublesome is the tendency to confuse that question with questions about the reality of hypnosis. Since the early 1960s, Barber20 and his students have systematically tried to study hypnosis by comparing individuals exposed to an induction procedure with individuals who


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are treated in a different fashion. Typically, few if any differences 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 that mimic the behavior 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 does Barber, 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 it 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 behavior and his verbal reports seem to indicate are the kinds of questions about the reality of hypnosis that 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. However, 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 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, one hopes, lay to rest the concern about this problem which has perhaps inadvertently been encouraged by some of the observations about hypnosis in recent years.


In his major monograph on hypnosis and suggestibility, Hull 19 set the standard for modern research in this field. Because it was time-consuming to


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identify highly responsive hypnotic subjects, he favored an experimental design comparing the response of the same individual while hypnotized with that while in a waking state. He carefully counterbalanced the order of 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 in the manner in which some instructions are given, and finally, from my point of view particularly important, the extent to which a within-subjects design can communicate what is expected -- or wanted -- of the subject's performance, convinced me that additional controls were required.27 I rejected an independent group design, ‡ 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. From the observation of 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 29 1 have described in detail the merits and demerits of using as a comparison group unhypnotizable subjects instructed to simulate hypnosis. 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 wake state. The simulating subjects who are run in exactly the same fashion as deeply hypnotized subjects have the purpose of establishing 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 hypnotized individuals. Rather, they indicate whether an unhypnotized subject could successfully mimic the behavior 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.§)

‡Independently, Sutcliffe 28 adopted in his own work an independent group design to minimize practice effects. Since his studies resulted in essentially negative findings, concerns about experimenter bias are not2 relevant criticism of his work. The issue of experimenter bias would become relevant only if he had found differences on the particular parameters he was examining. In such a case, one would be required to run additional studies in order to exclude the alternative hypothesis of experimenter bias that might account for differences.

§ 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 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


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It should be emphasized that simulating subjects must not receive any special training in 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 about the myriad assertions concerning changes that are unique to hypnosis, concerning abilities that are 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.*

An Example from Hypnotic Age Regression

A hypnotic phenomenon of both theoretical and practical importance is hypnotic age regression. In an early study,31 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 say to those who would argue that age regression is a full return to early childhood that this is not the case, but the cynic would seize upon such data to show that age regression is a fraud. If, however, it were a true 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 behavior can therefore be taken as evidence that we are not dealing with mere conscious role-playing and that, at the very least, the hypnotized individual's judgment is affected. Though 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

Footnote § cont.. from p. 23

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 stimulate in the comparison group. To distinguish definitively between these possible alternatives, additional experimental data are needed.

* As I have pointed out in detail elsewhere, our work should not be taken to suggest that the spontaneous simulation of hypnosis is a common occurrence. It rarely occurs in either clinical or experimental contexts, and as will be seen later, it should not be assumed to explain the hypnotic phenomena that are observed. Further, while I devised the real-simulator model to deal with certain kinds of methodological problems, it is by no means either an appropriate or necessary control in much hypnotic research.23,30


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regression. Reiff and Scheerer,32 in a major monograph, had compared the behavior of individuals age-regressed to ages ten, seven, and four, with role players instructed to role-play ages ten, seven, and four, respectively, using a variety of Piaget-type tasks and other behavioral items. One somewhat different test was devised by the investigators. While subjects were regressed to age four, playing in a sandbox, the experimenter asked whether the subject wanted a lollipop. All subjects responded affirmatively; he then removed the wrapper and handed to the 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 to 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 four-year-olds did under these circumstances. To our surprise, none of the four-year-olds was willing to take the lollipop by its eating end -- all sensibly insisting on taking it by the stick! 33

Other Issues of Transcendence of Normal Volitional Capacities

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, but 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.3 Simulating subjects can serve as an independent control group to study this kind of question.3, 5, 34, 35 To answer transcendence questions, task-motivated groups20 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 anesthesia, although we have long since learned to be cautious about even such improbable possibilities. At the present time we can only suggest that any claims for abilities unique to hypnosis require careful validation, using the real-simulator model.


As has been suggested earlier, the question that ultimately bothers the observer of hypnosis is whether the subject's behavior truly reflects what he


26 Annals New York Academy of Sciences

experiences. Does the hand that rises really feel light? As he struggles to separate his hands in a hand clasp, 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 neobehaviorist studies of hypnosis, probably because of the admittedly difficult problem of operationalizing subjective experience. Similarly, role theory,26 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 in which it has been discussed here. By the same token, role theory21 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, however, 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 behavior of the hypnotized individual would view the distinction between conscious and nonconscious role playing central to his understanding.˜

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 anesthetic. 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 anesthesia suggestions effectively alter the individual's experience.

Systematic studies, however, are perhaps more relevant in this context. Particularly interesting are those which 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 which 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.

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." Although 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 spontaneously* * reported seeing the chair through the hallucinated person.

˜ There is, of course, no doubt that phenomenologically, especially with subjects in the midrange of hypnotizability, one frequently encounters mixtures of conscious and nonconscious role playing. While there is a continuum in the relative amounts of volitional compliance and experiential changes that occur in individuals, it is nonetheless important to determine whether we are dealing with two distinct, qualitatively different processes.

* * Obviously, if simulating subjects are asked a direct question such as "Do you, or do you not, see the back of the chair through Joe?" (in a context where "Joe" was the hallucinated person), many will catch on to what is wanted and reply affirmatively,


27 Orne: The Construct of Hypnosis

The mixing of hallucination and percept seems to occur spontaneously only with those subjects who are deeply hypnotized. This finding has been corroborated in two independent experiments that have explored it.37,38

A related kind of phenomenon is source amnesia, studied by Evans 39 and Evans and Thorn.40 Here a subject in deep hypnosis is asked a number of questions, including some such as "An amethyst is a blue or purple gemstone; 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."

Such a response might possibly be taken as evidence that amnesia is not real, since the subject clearly has the information that he had presumably forgotten. However, the conclusion should be precisely the opposite. 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 had amnesia. In this instance, however, you need not accept my opinion. We have data! In a study 41 using reals and simulators, approximately a third of the deeply hypnotized subjects showed source amnesia, while not a single simulator ever admitted having known the answers to questions he had learned during hypnosis. On reflection it becomes clear that one needs to have amnesia in order not to recall the source of what has just been learned.

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.42 They had lost 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. 43

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 the, circumstances, simulating subjects did not respond, but 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. 44

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

Footnote ** cont. from p. 26

thereby eliminating any possible differences between hypnotized and simulating subjects (see Johnson et al.36).


28 Annals New York Academy of Sciences

every time you hear the word EXPERIMENT" -- even though the hypnotist had yet to count to three -- Sheehan45 carried out a series of studies that manipulated preexperimental 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, however, 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 Kihlstrom46 and Kihlstrom and Evans47 which investigates the effect of suggesting posthypnotic amnesia on the order of recall. These studies do not involve simulators; rather, they study an unsuggested consequence of suggested hypnotic amnesia where an unobtrusive measure in the sense of Webb et al.48 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 that 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.49 The disorganization of recall is thus an unsuggested consequence of a suggestion to have amnesia. It is, however, 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, 50 which replicates the finding of disorganized recall in hypnotized subjects but fails to find this effect in individuals given task-motivated instructions.


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 certain types of therapeutic changes 51 and was a powerful technique in controlling human behavior,52 that it made possible unusual feats of strength,19 unusual feats of memory,53 and unusual types of control over an individual's biological processes.54 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 research on hypnosis that has been accompanied by a distinct shift in the way hypnosis is perceived. Prior to that time, there had been a developing consensus that hypnosis was effective in bringing about of novel and more appropriate methodological approaches that challenged some of the widely believed and apparently well-established evidence 19 that hypnosis led to the transcendence


29 Orne: The Construct of Hypnosis

of normal volitional capacities. As this evidence became widely disseminated, it was inappropriately used for the argument 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 of simulators in research3 -- that despite the superficial similarity of the hypnotized individual's behavior, the underlying mechanisms are by no means identical. Thus, we have now shown with careful, detailed studies systematic differences that are likely to be a function of the hypnotizable individual's being hypnotized rather than due to the absence of simulation. 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 hypnotist 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 much of the circumstances of the real world, or whether the hypnotized subject is characterized as deluded,28 or as a form of role enactment,26 or responding to a believed-in imagining,21 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 who has been 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 pseudomemories. Indeed, perhaps the most striking characteristic we have noted about hypnotized individuals -- in contrast to simulators -- is their remarkable willingness to mix the experiences in the world suggested 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 the ultimate significance of the fact that some individuals can for a time alter their perception or memories. Is it merely a curious quirk of the mind that can be seen under some circumstances or does it reflect important processes that can have profound consequences, both therapeutically and for an understanding of human mental functions? Although I am firmly convinced the latter is true, much work needs to be done to characterize the difference between the effect of just 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 Bowers55 has aptly emphasized, that the simulating model is not suited to explore the effects of suggestions which are widely recognized and known within the subject population. 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 to be inevitably mimicked by all simulators. This should not be taken to mean, however, that these characteristics are therefore not typical of hypnotized individuals. The important systematic studies of pain and its sup-


30 Annals New York Academy of Sciences

pression by hypnosis carried out by Hilgard and Hilgard56 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.

Although studies using simulators and other related forms of comparison groups will continue to be 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,57, 58 ?s,59 and Tellegen and Atkinson,60 which has shown that an individual's tendency to have naturally occurring trancelike experiences or the ability for 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 that 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 searching 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. Instead, we are seeking to identify a variety of mechanisms that may be associated with hypnosis that may begin to provide an understanding of how hypnosis relates to other circumstances that involve the focusing 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.


31 Orne: The Construct of Hypnosis


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. Especial appreciation is due to Mae C. Weglarski for her editorial assistance.


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The preceding paper is a reproduction of the following article (Orne, M.T. The construct of hypnosis: Implications of the definition for research and practice. Annals of the New York Academy of Sciences, 1977, 296, 14-33. Copyright 1977 New York Academy of Sciences, U.S.A.). It is reproduced here with the kind permission of the New York Academy of Sciences.