USA
Recognizing that no satisfactory theory of hypnosis is currently available, I would like to contrast two points of view that have been the basis of a great many attempts to explain and understand the phenomenon. One view holds that inducing hypnosis brings some kind of altered state of functioning in the individual, perhaps associated with unspecified but potent neurophysiological alterations. This is a traditional position, held by investigators with varying views from CHARCOT to PAVLOV to FREUD. While this position is still widely held today, it has also been challenged. From the beginning some observers have noted inconsistencies in hypnotic behavior and have questioned the extent to which basic changes within the subject are necessary to understand what occurs. In the older literature, concepts such as "imagination", "responding to the authority of the hypnotist", "cooperation", and so on, are evoked. More recently, similar views have been expressed in motivational terms which focus on the subject's desire to be hypnotized and acting accordingly. Role theory, most clearly explicated by SARBIN (1950) has conceptualized hypnosis as playing the role of a hypnotized subject.
It must be recognized, of course, that those students of hypnosis who see it as an altered state also are aware of inconsistencies and a certain histrionic quality of much somnambulistic behavior. SARBIN, on the other hand, speaks of role playing at a non-conscious level, a view which cannot easily be operationally delineated from a state theory. Not surprisingly, most theorists recognize that some aspects of hypnosis can better be understood in
2 I wish to thank my colleagues, HARVEY D. COHEN, FREDERICK J. EVANS, KENNETH R. GRAHAM, GORDON A. HAMMER, EMILY C. ORNE, and DAVID A. PASKEWITZ for their helpful comments in the preparation of this paper.
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terms of an altered state while other aspects appear to fit a role playing model. At the same time, there has been a loose parallel between those theorists who took what SUTCLIFFE (1960) has called a "credulous view" of the phenomenon, accepting a state theory, whereas those who pride themselves on taking a skeptical, hard-nosed position have generally leaned toward a role theory.
Recent work, most notably by BARBER and his associates, has explicitly argued that hypnosis is neither a useful construct nor is it necessary to assume that there are any alterations in basic mechanisms to account for the phenomena. They believe all aspects of hypnosis can adequately be explained in terms of the context, the motivation of the subject, and the role he tries to play.
This position has attracted considerable attention, particularly in the United States, since it is phrased in a rigorous operational framework. The importance of translating concepts into operational terms is generally accepted by American psychologists and has led to the conceptual clarification of many issues. It is crucial, however, to understand precisely how a given investigator operationalizes the concepts he hopes to study, since it is easy to do considerable violence to what others believe the concept to mean. It seems desirable, therefore, to contrast the way hypnosis is operationalized by BARBER and his students as opposed to the somewhat more traditional approach upon which this paper is based 3.
In brief, BARBER (1969) defines hypnosis as that which results when a subject has been exposed to a hypnotic induction procedure. It is the situation and the behavior of the hypnotist which are seen as the independent variables leading to hypnosis. If a group of subjects are exposed to a trance induction procedure they are defined as being the hypnotized group regardless of the extent to which any of the subjects may be affected by such a procedure. Indeed, those characteristics of subject response which are traditionally seen as diagnostic of hypnosis are viewed as the dependent variables.
In many studies BARBER has demonstrated that the presence of hypnosis -- in other words, a formal induction procedure -- makes remarkably little difference when compared to imagination or motivational instructions without a formal trance induction procedure. The dependent variables in each instance are the four domains of behavior usually seen as defining hypnosis:
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the response to test suggestions, hypnotic appearance, reports of unusual experiences, and testimony of having felt hypnotized.
It should be noted that this view is almost diametrically opposite to our approach. Here it is recognized that wide individual differences exist in subjects' response to a trance induction procedure. Some subjects enter hypnosis with little or no formal induction, while others fail to respond despite their own cooperation and the hypnotist's most strenuous efforts. For this reason it is generally acknowledged that hypnotic induction procedures are a sufficient condition to induce hypnosis in some but by no means all subjects; further, that they are not a necessary condition for some subjects. Consequently, the presence of hypnosis is inferred from the subject's response to test suggestions, his appearance, and what may be inferred about his subjective experience from what he reports rather than from the behavior of the hypnotist. The presence of hypnosis is diagnosed much in the way one would diagnose the presence of depression. While in borderline cases such a determination is difficult to make reliably, there is little difficulty for reasonably trained observers to agree when subjects manifest the classic symptoms. For research purposes one selects those subjects where the presence of hypnosis can be reliably diagnosed by independent observers. Under these circumstances hypnosis becomes the independent variable rigorously defined by specified responses of the subject. One then is able to ask how a hypnotized individual responds differently. To do so the hypnotized individual's behavior may be compared with his own behavior when he is not hypnotized or with the behavior of other individuals who do not respond to hypnotic induction procedures.
Following the views of WHITE (1941), I had initially accepted both role playing and increased motivation, as well as an altered state of consciousness, as factors in hypnosis. From the point of view of understanding the effects of an altered state the other components were a kind of artifact that had to be understood and controlled. Because these views had largely been ignored, my own early efforts focused on clarifying the extent to which hypnosis could be understood in terms of role playing and altered motivation. Since then the once remarkable observation of how many effects of hypnosis could be duplicated without hypnosis has become so commonplace that the very existence of the phenomenon appears to have been questioned. It is the purpose of this paper to bring together some observations, obtained under controlled conditions, that some aspects of hypnosis cannot be explained as compliance, as playing the role of a hypnotized subject, or acting to please the hypnotist.
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Evidence for a less adequate response to hypnotic suggestion than to wake request
In several studies it has been observed that the deeply hypnotized subject does not perform as well on some tasks as individuals who are asked to play the role of a hypnotized individual. P. C. YOUNG, as early as 1937, carried out a study on hypnotic age regression which showed that non-hypnotized controls were better able to mimic the performance of a child on the Binet test than subjects who were hypnotized and age regressed. He concluded at the time that the hypnotized individual plays a role with all his heart but not all of his mind.
I was able to observe a similar performance, using drawing tests in hypnotic age regression. In studies of posthypnotic behavior, HULL (1933), citing work by KELLOGG (1929) and subsequently by PATTEN (1930), makes similar observations. These investigators asked subjects to carry out a posthypnotic suggestion such as: when reading poetry, to read faster on the even-numbered pages than the odd-numbered pages. The effect of the posthypnotic suggestion could be shown to decay rapidly over time whereas a simple request to control subjects resulted in stable, persistent behavior over many weeks.
In the above studies, hypnotizability was not kept constant. This was done by DAMASER (1964) in our laboratory who studied the effect of posthypnotic suggestion over a long period of time. In this experiment, subjects were given a stack of 100 postcards and requested to send one daily to the laboratory. This task had previously been shown to be responsive to experimental laboratory manipulation. Highly hypnotizable subjects were randomly assigned to three groups. The first group was deeply hypnotized; then, while in hypnosis, they were given the 100 postcards and the posthypnotic suggestion to send one daily to the laboratory, awakened and sent home. The second group was deeply hypnotized, given the identical posthypnotic suggestion, and then awakened. In the wake state they were also shown the 100 postcards and asked to send one to the laboratory daily. Thus this group served as both a posthypnotic suggestion and a waking request group. Finally, the third group was deeply hypnotized but given no posthypnotic suggestion, awakened and then, in the wake state, was shown the 100 costcards and asked to send one to the laboratory each day. The same procedure was carried out with another group of subjects who were hypnotizable but not able to attain consistent amnesia. The findings of the study were clear. The waking request groups sent significantly more postcards than the posthypnotic suggestion alone groups.
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Data such as these suggest that in some circumstances hypnotic suggestion may actually interfere with the performance of some experimental tasks. These findings are inconsistent with the notion that hypnosis is merely a function of the individual's playing the role of a subject, particularly since all subjects tend to believe that hypnosis is an extremely effective means of controlling behavior, a conviction that is disconfirmed by the way they behave in these studies.
Evidence for conditions when hypnotic suggestion leads to an increased response
Another study of posthypnotic behavior (ORNE, SHEEHAN and EVANS, 1968) carried out in our laboratory in collaboration with Drs. SHEEHAN and EVANS addressed this problem in an entirely different way. This concerned an extension and replication of SEYMOUR FISHER'S (1954) classic study of the relationship between expectations and posthypnotic response. In an ingenious experiment, FISHER suggested to deeply hypnotized subjects that, on awakening, each time they heard the word Psychology they would scratch their right ear. After waking the subjects he tested the suggestion by using the word and was able to elicit the suggested behavior. At this point one of his associates came into the room and by innuendo the experiment was terminated. The associate, Dr. FISHER, and the subject entered into an informal conversation about current topics of the day. In the course of this informal conversation at the conclusion of the study, the word Psychology came up spontaneously. Of the 12 subjects, only 3 responded during this time. After some minutes of conversation the associate left and FISHER, turning back to his subjects, would by implication continue the experiment and would conspicuously use the word Psychology in a sentence. Under these circumstances all of his subjects resumed responding by scratching their right ear. When asked about their behavior during the preceding period, several of the subjects erroneously insisted that they had continued to respond, while others gave very transparent rationalizations. From this study FISHER concluded that the posthypnotic response is a function of the subject's expectations of what is desired and would be carried out only as long as he believed the experiment to be in progress.
We hypothesized that it was plausible that in the FISHER study subjects perceived the original suggestion to be that they ought to respond by scratching their right ear in response to the word Psychology as long as the experiment continued since the request to do so indefinitely would not be a plausible one. If this were actually the case, one would expect the subjects
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to stop responding when they believed the experiment to be over, and this finding would not necessarily have any implications for the persistence of a different kind of posthypnotic suggestion outside of the experimental situation. From our point of view the FISHER study does not really test whether a subject who is given a clear-cut, time-limited posthypnotic suggestion will carry it out even under circumstances which he perceives to be outside of the experiment, where the hypnotist would be unlikely to know or even care whether the suggestion had been carried out. This question addresses itself to the issue of whether the posthypnotic response is a function of the suggestion given during hypnosis or whether it is an attempt by the subject to please the hypnotist, depending, as it were on the ongoing relationship.
An experiment was carefully designed (ORNE, SHEEHAN and EVANS, 1968) which would require that the subject come to the laboratory on two succeeding days and take a number of personality tests, some while hypnotized. Subjects were informed in advance that they would be required to come on two successive days. The first day, in addition to taking a number of tests which were, in fact, part of another experiment, subjects were given the suggestion in deep hypnosis that for the next 48 hours each time they heard the word Experiment they would run their right hand throught their hair. It should be noted that this suggestion was legitimized by the fact that subjects knew that they would see the hypnotist on the succeeding day. The suggestion itself, however, was clear-cut and explicit in placing a 48-hour time limit on its effectiveness.
The next day when the subject came to the laboratory the experimenter was informed by the receptionist of his arrival and on meeting him in the waiting room and walking down the hall to the experimental room, that the experimenter would carefully say, "I appreciate your coming back to the Experiment". This test, however, was not the crucial measure of the posthypnotic response.
Subjects taking part in our research are paid for their participation, and it is customary for them to return to the main office at the completion of a study where, after signing a receipt, they are reimbursed for their time. Each subject, on the completion of the first day's tests, returned to the secretary who asked him to sign the usual form, asking whether it would be all right to pay him "now for today's Experiment and for the next part of the study tomorrow". The subject's response under these circumstances, in a different room totally outside the experimental context, constituted the first criterion test. On returning the subsequent day the subject was met by the receptionist who asked whether he was participating in the physiological or the psycho-
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logical Experiment -- two studies that were in progress as the same time. The subject's response to the receptionist constituted the second test.
The results showed that, using a highly selected group of subjects who were capable of entering deep hypnosis, subjects responded in the waiting room and the main office as much as they had in the presence of the hypnotist. Thus, in some instances, since the word Experiment was used quite casually, subjects did not always seem to hear the cue; on the other hand, the fact that the context was different, the experimenter was not present, and that the test was carried out in a way that appeared totally unrelated to the study, did not seem to interfere with the response. Interestingly enough, those subjects who responded most consistently were those individuals who also were most deeply hypnotized.
One thorny methodological problem in this study was whether the subjects perceived the test by the secretary to be truly outside the experimental session. If somehow the way in which this study was carried out permitted the subjects to suspect that the secretary was really recording their behavior for the benefit of the hypnotist, the findings would have little relevance to the extent to which the posthypnotic response generalizes from one context to another. Obviously it would have been most desirable to test the posthypnotic suggestion totally away from the laboratory. However, even if we had done so, it would still have been necessary to ask whether the subject might not have suspected what we were doing. For this reason we ran a special treatment group of simulating subjects.
This approach was developed some years ago in order to have a comparison group which was not hypnotized but exposed to the identical cues as the hypnotized individuals. For this purpose it would be vital that the hypnotist be unaware whether a given subject was actually hypnotized or simulating. Only in this way could one be certain that the hypnotist's behavior would be truly similar. The literature had asserted that subjects were unable to simulate hypnosis successfully. When we asked subjects to do so, their behavior was clearly transparent. Typically, they would simulate for a minute or two, would look at me, smile, ask me if they were doing all right, and, in many ways, betray their discomfort and display their inability to carry out the requested task. Reflection clarified why. Subjects were asked to simulate knowing that we knew that they were simulating. Regardless of how well they might do in the task, success was impossible. They found the request unpleasant and experienced the situation as one where they could not win. When this procedure was modified by asking individuals who were unable
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to enter hypnosis to simulate doing so they were given instructions as follows: "I want you to go in with Dr. X who is an experienced hypnotist. In the past you have tried to enter hypnosis and have been unable to do so. In this experiment your task is to make believe -- to simulate -- to fake entering hypnosis. Dr. X will know that some people are simulating but he does not know who. Don't think you have given yourself away because as long as he continues the experiment you are being successful in fooling him. If he catches on to the fact that you are faking he will stop the experiment immediately. I cannot tell you what to do or how to behave. You have to do the best you can. While this is a difficult task, we have found that some intelligent subjects are able to accomplish it successfully. Good luck!" This simple instruction dramatically altered the situation and we found, somewhat to our chagrin, that subjects were able to simulate sufficiently well to deceive even highly experienced hypnotists.
I would like to emphasize that simulating subjects do not, except in very rare instances, enter hypnosis. They do, however, provide an extremely important and useful comparison group which allows the investigator to determine what aspects of the hypnotized individual's behavior could conceivably be accounted for in terms of his expectations. Let me emphasize that this is not a simple control group; it is a comparison group which allows very limited inference and is only useful to answer specific kinds of questions. The group is maximally motivated to respond to subtle cues and tends to be particularly suspicious in the situation. Therefore it provides an especially rigorous test of the adequacy of an experimental deception.
Parenthetically, our finding that simulating subjects could mimic the behavior of deeply hypnotized individuals on a wide variety of tasks has been erroneously interpreted to mean that there is no difference between these two groups. No such inference is justified; indeed, there is good reason to believe that entirely different mechanisms are involved in producing the behaviors. The importance of the technique is in clarifying the kind of cues that are available to the hypnotized individual and the kind of abilities available to non-hypnotized subjects.
In this context, then, the simulating subjects allowed a hard test of the question as to whether the receptionist was perceived as part of the experiment. Both groups of subjects were run randomly intermixed. Without knowing to which group any given individual belonged, we found that of 17 deeply hypnotized subjects, 6 responded on both days, whereas of the 13 simulating subjects, not one subject responded on both days. These differences are particularly striking since in the presence of the hypnotist the
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simulating subjects tended to respond more often, but in his absence the probability of their response was significantly less.
Looking at this issue from a somewhat different point of view, we explored the proposition that hypnosis increases the motivation of the subject to comply with the wishes of the hypnotist, a formulation which I initially put forth and that seemed so self-evident and intuitively correct that it had gone unchallenged for a number of years. However, on more careful examination it became clear that no such increased motivation to please the hypnotist could be demonstrated in the laboratory. Elsewhere (ORNE, 1966, 1970) we have examined these data in detail. Suffice it to say that a deeply hypnotized individual is not more likely to be compliant on tasks which in and of themselves do not require the presence of hypnosis than individuals who are unhypnotized or unable to enter hypnosis.
A final study (EVANS, 1966; ORNE and EVANS, 1966) which bears directly on this issue is an empirical investigation of a question that is sometimes asked by patients who have ambivalent feelings about hypnotherapy: "What happens if you drop dead while I am hypnotized?" The thinly disguised hostile question is generally answered in the classic text by indicating that if the hypnotist somehow leaves without warning subjects will gradually go into normal sleep from which they will eventually awaken. Actually, however, there are no data to support this view and the question is by no means easy to examine. The hypnotist's disappearance must be managed in such a way as to seem plausible and truly accidental in order to avoid doing violence to the implicit agreement between subject and hypnotist that the latter is responsible for the welfare of the former during the course of the experiment. Such a situation was finally created in a study requiring two sessions with subjects previously trained to enter hypnosis readily. It was explained to them that in order to standardize the procedure all instructions, including the induction and termination of hypnosis, would be carried out by tape recording.
The experimenter's task was essentially that of a technician -- turning on the tape recorder, applying electrodes, presenting experimental materials, etc. He did not say anything throughout the study since every item of instruction was given by means of the tape recorder. Each subject came for two such sessions. During the second session, while the subject was deeply hypnotized and tapping his foot in rhythm with hallucinating music, the tape recorder came to a grinding halt, the light went out on the desk, and the experimenter tried in vain to reactivate the machine by flicking the switch. He then
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muttered under his breath that the fuse must be blown and dashed from the room.
The subject's behavior was observed through a one-way screen through out the experiment in order to determine what would happen once the experimenter had left the room. Would hypnosis be terminated immediately once the subject was alone as some theories would predict, or would it take a period of time for the subject to pull himself out of hypnosis as one would expect if the condition were some special altered state?
Despite the "cuteness" of the deception procedure of the simulated power failure there was no certainty whether the subject would accept it as such. For this reason a comparison group of simulators was run. The findings were clear-cut: five out of the six deeply hypnotized subjects did not arouse immediately when the hypnotist left. They required varying periods of time to apparently pull themselves out of state. When they did, they appeared somewhat disoriented and confused. In contrast, five out of the six simulating subjects continued to simulate hypnosis for the whole half-hour period until the technician returned, presumably having fixed the fuse. During the subsequent postexperimental inquiry it became clear that the simulators caught on to the fact that the power failure was contrived and that they behaved as they thought a hypnotized subject would if there were a true power failure. The simulating subjects quite cogently pointed out that having been instructed to fool the experimenter put them on their guard lest they themselves be fooled. In contrast, only one of the hypnotized subjects suspected that the power failure was contrived.
Because the simulating subjects are a special treatment group their purpose is not primarily as a comparison with actual subject populations; rather, it is to clarify the adequacy of the experimental procedure. Since the simulators caught on to the fact that the power failure was contrived it was plausible that at some level the hypnotized subjects could have responded to the same cues though they did not verbalize such awareness. Therefore despite statistically significant differences between these two groups these results do not permit any conclusions to be drawn about the nature of the hypnotic phenomenon. The behavior of the simulators demonstrates an inadequacy of the deception procedure and indicates that the behavior of the hypnotized subjects could not be interpreted at face value.
Having found the reception manipulation wanting, we re-examined in detail the cues which might allow the subject to become aware that the power failure was a planned part of the experiment and that his behavior would actually be observed subsequent to it. The kind of nitty-gritty details
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which most investigators fail to publish and which, even if they wished to, most editors will delete for the sake of brevity, are crucial in this regard: to wit, in the study just described, to facilitate observation after the "power failure", the overhead lights remained on and only the bright desk lamp went out as the tape recorder stopped; an obvious one-way mirror had always been in the room to which we had hoped (in vain) the subject would have adapted further, a small polygraph continued to run in the experimental room after the "power failure", etc. We now redesigned the study with considerable attention to such details. The one-way screen was eliminated and replaced by another less well-known and carefully hidden means of observation. When the power failure occurred, all lights in the room were extinguished. Just enough light was filtered into the room through the window curtains from daylight -- or from a strategically placed parking light outside at night -- to make observation possible. Furthermore, physiological recordings were made by means of a large Ampex instrumentation tape recorder and a small polygraph. Both of these machines stopped, along with the lights and the tape recorder, with the power failure. (Actually, the wires from the subject were run through to another room at some distance in order to permit continuous recording of relevant data.) When the experimenter left the room the hall lights were out. Every effort was made by scrupulous attention to such details to make the power failure plausible.
With these revised conditions simulating and hypnotized subjects were run in another experiment by a blind experimenter. Here five out of six simulating subjects stopped simulating the moment the technician left the room, indulging in exploratory and other private behavior clearly indicating that they felt themselves to be unobserved. On the other hand, the hypnotized group behaved much as they had in the earlier experiment, pulling themselves out of this state only after a considerable period of time had elapsed. This behavior was in line with the data provided during an inquiry, indicating that both real and simulating subjects accepted the power failure as genuine.
Significant differences were again obtained but, in contrast to the findings of the first study, those from the second study allow meaningful inference. The behavior of the simulators clearly indicates that the power failure was accepted as genuine and therefore it is plausible to accept the behavior of the hypnotized individuals at face value.
Perhaps it seems superfluous to this audience to prove in such an elaborate fashion that hypnosis is experienced as real by the subject and to demonstrate that simple compliance or role playing cannot account for the phenom-
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enon: rather that hypnosis can better be conceptualized as an altered state though no defining or unique neurophysiological changes have thus far been identified with it. Possibly this is self-evident to any investigator who has worked extensively with hypnosis. However, having seen the pendulum of scientific opinion swing from a rather credulous acceptance of quasi-magical notions of hypnosis to a position where, at least in the United States, it has again become fashionable to deny the very existence of the phenomenon, I felt it necessary to demonstrate the obvious in a rigorous way. Having established once again that there are a number of striking, real and unexplained phenomena, it may now be possible to focus on more basic questions concerning the nature of hypnosis. Hopefully the trend of current work that identifies artifacts as such without thereby failing to recognize what we yet need to understand will hasten the day when an adequate theory of hypnosis can be developed.
SUMMARY
Traditionally hypnosis had been seen as a distinct altered state but recent studies challenge this view. Evidence will be reviewed which supports the traditional concept of hypnosis and indicates that neither compliance nor the wish to please the hypnotist can adequately explain the phenomena of deep hypnosis.
REFERENCES
BARBER, T. X.: Hypnosis: A scientific approach. New York: Van Nostrand, Reinhold 1969. -- DAMASER, E.: An experimental study of long-term post-hypnotic suggestion. Diss. Harvard Univ., Cambridge, Mass. 1964.-- EVANS, F. J.: The case of the disappearing hypnotist. Paper read at Amer. Psychol. Ass. New York, September, 1966. -- FISHER, S.: The role of expectancy in the performance of posthypnotic behavior. J. abnorm. soc. Psychol. 49, 1954, 503-507. -- HILGARD, E. R.: Hypnotic susceptibility. New York: Harcourt, Brace & World 1965. -- HULL, C. L.: Hypnosis and suggestibility. New York: Appleton-Century 1933. -- KELLOGG, E. R.: Duration of the effects of post-hypnotic suggestion. J. exper. Psychol. 12, 1929, 502-514. -- ORNE, M. T.: The nature of hypnosis: Artifact and essence. J. abnorm. soc. Psychol. 58, 1959, 277-299. -- ORNE, M. T.: Hypnosis, motivation and compliance. Amer. J. Psychiat. 122, 1966, 721-726. -- ORNE, M. T.: Hypnosis, motivation and the ecological validity of the psychological experiment. Paper read at Nebraska Symposium on Motivation, Lincoln, March, 1970. -- ORNE, M. T., & EVANS, F. J.: Inadvertent termination of hypnosis with hypnotized and simulating subjects. Int. J. clin. exp. Hypnos. 14, 1966, 61-78. -- ORNE, M. T., SHEEHAN, P. W., & EVANS, F. J.: Occurrence of posthypnotic behavior outside the experimental setting. J. Personality and soc. Psychol. 9, 1968, 189-196. -- PATTEN, E. F.: The duration of posthypnotic suggestion. J. abnorm. soc. Psychol. 25, 1930, 319-334. -- SARBIN, T. R.: Contributions to role
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taking theory: I. Hypnotic behavior. Psychol. Review 57, 1950, 255-270. -- SUTCLIFFE, J. P.: "Credulous" and "sceptical" views of hypnotic phenomena: A review of certain evidence and methodology. Int. J. clin. exp. Hypnos. 8, 1960, 73-101. -- WHITE, R. W.: A preface to a theory of hypnotism. J. abnorm. social Psychol. 36, 1941, 477-505. -- YOUNG, P. C.: The veridicality of hypnotically induced regression. Psychol. Bull. 34, 1937, 784.
Address of the author:
Prof. M. T. Orne, M. D. Ph. D., I11 North 49th Street, Philadelphia, Pennsylvania
(USA)