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Evans, F. J., & Orne, M. T. The disappearing hypnotist: The use of simulating subjects to evaluate how
subjects perceive experimental procedures. International Journal of Clinical and Experimental Hypnosis,
1971, 19, 277-296.
THE DISAPPEARING HYPNOTIST: THE USE OF SIMULATING SUBJECTS TO EVALUATE
HOW SUBJECTS PERCEIVE EXPERIMENTAL PROCEDURES 1
FREDERICK J. EVANS AND MARTIN T. ORNE 2
Institute of the Pennsylvania Hospital and University of Pennsylvania
Abstract: This study examines the effects of a temporary power failure while S was hypnotized during a
tape-recorded session. It was necessary that the power failure be perceived by S as an accident and not as
an experimental deception. In a previous study (Orne & Evans, 1966), Ss simulating hypnosis with a
"blind" E continued faking throughout the "power failure," apparently suspecting they were being
observed. Therefore, no conclusions could be drawn about the behavior of the hypnotized Ss. After the
procedure was modified, simulating Ss ceased faking as soon as the hypnotist left the room, thereby
demonstrating that they believed that a power failure had actually occurred and that they were not being
watched. Hypnotized Ss spontaneously, although slowly and with subjective difficulty, terminated
hypnosis by themselves. The spontaneous behavior of the hypnotized Ss in the absence of a hypnotist
seems inconsistent with predictions based on motivational or role-taking theories of hypnosis.
The current major theories of hypnosis agree that individual difference, motivational, and interpersonal
factors are important components of the phenomenon. Some theorists (e.g., Barber, 1969; Sarbin, 1950)
have argued that these aspects are wholly sufficient to explain hypnosis, while others (e.g., Hilgard, 1965;
Kubie & Margolin, 1944; Orne, 1959) insist that, in addition, hypnosis involves an altered state of the
individual. Because there is considerable overlap in these views, it has been difficult to operationalize the
differences. One situation in which these
Manuscript submitted January 17, 1971.
1 This study was supported in part by contract Nonr-4731 (00) from the Office of Naval Research and by
grant MH 19156-01 from the National Institute of Mental Health, Public Health Service.
2 Several colleagues were involved in the successful completion of this investigation. We wish to thank
Barbara Marcelo, St. Christopher's Hospital for Children, Philadelphia, for her role as the blind E and
Mary Jo Bryan for her help as technician. The comments of Harvey D. Cohen, Mary R. Cook, A. Gordon
Hammer, John F. Kihlstrom, William A Mitchell, David A. Paskewitz, and especially Charles Graham and
Emily Carota Orne were particularly valuable. We also wish to thank Howard A. Kaiser, Betty H. Marx,
Toby L. Parcel, and Susan Jo Russell for their help in various ways.
277
278 EVANS AND ORNE
differing theoretical views should lead to different predictions is the rather unlikely event that the
hypnotist is prevented from terminating hypnosis. Occasionally an anxious patient may ask, "What would
happen if the hypnotist had a heart attack while I was hypnotized ?" Dynamic implications aside, this
question is concerned with whether hypnosis must be terminated by the hypnotist or whether it is
contingent upon a continuing interpersonal relationship and would therefore become terminated
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automatically if the hypnotist became unavailable. The purpose of this paper is to present an empirical test
of this question.
State and Motivational Theories of the Termination of Hypnosis
"Motivational" and "role playing" theorists regard hypnosis as a special kind of interpersonal relationship
between S and the hypnotist which motivates S to behave like a hypnotized person or to enact the role of
a hypnotized individual. The induction of hypnosis consists of establishing this special role relationship. If
hypnosis does not exist beyond this specifically defined relationship, one would predict that the
disappearance of the hypnotist would automatically and immediately terminate hypnosis. If the special
relationship does not continue, then hypnosis cannot exist. 3 The major difficulty with operationalizing a
test of this view involves defining the hypnotic relationship as ended in a way that permits a test of the
continuation of the hypnotic effects without reinstating the special relationship.
Adherents of a "state" approach argue that hypnosis involves a qualitative change in the organism.
Hypnosis is a special condition within the hypnotized individual -- in particular, an altered state that allows
Ss to experience distortions of perception and memory as subjectively real. Although individual
difference, motivational, and interpersonal factors are important in bringing about the induction and
termination of hypnosis, hypnosis cannot be accounted for by these factors alone. Regardless of how
hypnosis is initiated, it involves changes within the individual and, consequently, if the hypnotist
disappeared, hypnosis would not automatically cease. On the contrary, time and effort would have to be
expended by the individual to reverse the
3 In our attempt to derive a testable hypothesis differentiating the two types of theories of hypnosis, we do
not claim that adherents of either theory have even implicitly made these predictions. Thus, Sarbin (1950)
has argued that role involvement may not be at a conscious level. It seems that such a view cannot
spontaneously be distinguished from a state theory. Nonetheless, if the defining relationship is stressed as
the means by which role taking is established (Barber, 1969; Sarbin, 1950; Sarbin & Andersen, 1967),
then the termination of the relationship ought to terminate the need to continue the role.
279 THE DISAPPEARING HYPNOTIST
altered state of consciousness and attention which these theorists believe constitutes a significant aspect of
hypnosis.
What Happens if the Hypnotist Does Disappear?
Historically, a variety of opinions have been expressed about the fate of a hypnotized S suddenly and
unexpectedly left alone (see Orne & Evans, 1966). Although it has been generally held that under these
circumstances a deeply hypnotized S would eventually lapse into normal sleep from which he would
ultimately arouse himself, little empirical evidence is available. The only directly relevant study was
conducted by Dorcus, Brintnall and Case (1941). The secretary interrupted a session while S was deeply
hypnotized and reminded the hypnotist -- sufficiently loudly for S to overhear -- of an important
appointment downtown. The hypnotist left immediately without any word to S. Twenty Ss remained
hypnotized, defined in terms of the length of time they stayed in the experimental room, for a mean time
of approximately 28 minutes. The control group of 25 "relaxing" Ss remained for a shorter period of
approximately 20 minutes. However, no systematic attempt was made to determine whether Ss perceived
E’s departure as genuinely due to external demands or whether they recognized the situation as an
experimental manipulation. Therefore the interpretation of these results remains equivocal. 4
It is difficult to envisage a situation in which a hypnotist can legitimately disappear without creating
suspicion or, worse yet, disturbing the rapport between himself and S. Few appointments or emergencies
are sufficiently urgent that a hypnotist who is genuinely concerned for the welfare of his S can simply
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disappear without having some time available to terminate hypnosis, apologize, and explain his
predicament to S. It is implicitly part of the rules on conducting experimentation that E concern himself
about S’s welfare. Therefore, unless the hypno4 Due to a printer's error, it was reported in our earlier study (Orne & Evans, 1966) that the control group
mean was 23 minutes instead of 20. The difference between the two groups is still, however, insignificant
(t = 1.6). As Dorcus et al. (1941) reported their data in rather broad categories, this t test might be
misleading. The data were grouped in 10-minute intervals up to 50 minutes; this interval was scored as 55,
which leads to a very conservative t-test. Dorcus et al. (1941) reported that the two control Ss, who
remained with their eyes closed for "50 minutes and over," did so for a shorter time than the seven
hypnotized Ss who fell into this category. This difference is significant (p < .05, one-tailed Fisher's exact
test). The control Ss performed in a fashion similar to the simulating Ss who were not deceived, i.e., the
unhypnotized Ss continued with the experiment in a way that is consonant with the expectation that
hypnotized Ss would remain hypnotized.
280 EVANS AND ORNE
tist's disappearance is caused through no fault of his own, the situation seems implausible. It is likely that
S’s credulity was strained by the inappropriately abrupt departure of the hypnotist in the study by Dorcus
et al. (1941).
A more satisfactory method of conducting the relevant experiment is suggested by the use of a tape
recording to induce hypnosis. Provided S is capable of experiencing deep hypnosis when it is induced by
the hypnotist's tape-recorded voice, the special hypnotic relationship or rapport, to the extent that it can
be said to exist, is between the voice on the tape recorder and S. A sudden, mechanical failure of the tape
recorder provides a plausible and dramatic method of interrupting hypnosis. By a fortuitous accident,
hypnosis can be interrupted precipitously in a fashion which will not interfere with S’s relationship with
the laboratory. The hypnotist "disappears," as it were, through no fault of his own. The crucial issue in this
design then becomes: Can a sudden mechanical failure be created artificially, yet still be able to bring
about a situation in which S perceives the accident as genuine? Or, does the artificiality of the situation
override the more subtle aspects involved in the hypnotist's abrupt departure? 5
Deception, Plausibility, and Empirical Validation
To obtain meaningful evidence about the specific outcomes predicted by the two different theoretical
points of view, it is necessary that the experimental situation be perceived by S as E intends it to be seen:
the hypnotist's disappearance must be perceived as truly accidental, not as a planned part of the
experiment nor as unprofessional or inappropriate. It is not sufficient to end an experiment by an act of
fiat on the part of E. Such a situation undoubtedly would be highly anxiety-provoking for some Ss, and
would fail to deceive others.
Evaluating the success of justifiable deception in psychological experiments is difficult. Even when the
deception seems highly plausible at face value, the active role played by S in a psychological experiment
(Orne, 1959; Orne, 1962; Orne & Evans, 1965) makes it mandatory that his perceptions in the situation be
evaluated. Typically, a pact of ignorance is established in which S does not wish to indicate that he has
seen through E's deception (for that would invalidate his own experi5 The relationship as such is not interfered with in the long-term view of the interaction; however, at least
during the interval while the tape is not playing and the observer is not present, no object of interaction
exists with whom to play the defined role or to define what a good S is supposed to do. In this reciprocal
sense, if these aspects are the features which define the occurrence of hypnosis, S would have no reason
for continuing to be hypnotized.
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281 THE DISAPPEARING HYPNOTIST
mental results), nor does E wish to discover that Ss were not as naive as he had hoped (for that would also
invalidate his experiment!). 6 The psychopharmacologist has developed a partial solution with the
double-blind methodology. For the social psychologist who employs deception as a tool, the problem is no
less acute (Stricker, 1967).
The Simulation Design and Evaluating Deception
Orne (1959, 1962, 1970, 1971, in press) has proposed several strategies (not strictly control groups in the
classical sense) for evaluating S’s perceptions about the nature of the experimental procedure. One such
strategy particularly suited to hypnosis research is that of Ss' simulating with a "blind" E. A S who is
insusceptible to hypnosis is asked to simulate the performance of deeply hypnotized Ss. Provided E is
blind to the identity of both real and simulating Ss, he cannot reliably detect which S is which by observing
the classical hypnotic phenomena. 7 This technique is particularly well adapted to exploring S’s potential
awareness of deception.
There are two special features of the simulating technique: (a) Both hypnotized and simulating Ss are
treated alike. As E is "blind," he cannot provide cues for the hypnotized Ss which are not also provided for
simulators. (b) The behavior of simulators provides a means of evaluating the contribution of Ss'
expectations and perceptions in accounting for the obtained results.
Specifically, the behavior of simulating Ss in the present study will provide evidence about two important
aspects. First, their behavior during the "accidentally" produced power failure will provide clues about the
plausibility of the deception. Depending on their reaction to the cessation of the tape recording, it will be
possible to evaluate whether already suspicious Ss perceive the power failure as a deliberate manipulation
by E or whether they accept it as a plausible accident. Only when these highly suspicious Ss accept the
procedure as a genuine power failure can meaningful conclusions be drawn about what
6 For an example of a highly plausible deception and subsequent evidence suggesting that the existence of
such a pact of ignorance in fact raises questions about the generality of the obtained results, see Milgram's
(1965) studies on obedience and a critique of this work by Orne and Holland (1968).
7 Although special experiments can be designed to differentiate real from simulating Ss, the experimental
model uses simulators as a quasi-control group to evaluate the experimental procedure. Under these
circumstances, the intent is not to study whether the two groups of Ss can be differentiated. Fortunately,
the cues available to the hypnotist in conducting typical hypnotic experiments are not sufficient to
discriminate between these two groups. Therefore, the E remains blind as is required by the model.
282 EVANS AND ORNE
hypnotized Ss would do in such an emergency. Secondly, as a further check on the validity of the
experiment, the behavior of the hypnotized Ss can be evaluated against the performance of the simulating
Ss in terms of how they would expect a hypnotized person to react in such an emergency.
An Unsuccessful Study -- As Indicated by Simulating Ss
A study (Orne & Evans, 1966) was designed in which a tape recorder served as the hypnotist. While S
was carrying out several suggestions (his arm stuck to the chair, his eyes glued together, his foot keeping
time with hallucinated music), a switch was thrown, shutting off a bright desk light and bringing the tape
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recorder to a slurring halt in mid-sentence --presumably a power failure. The E unsuccessfully tried to
restart the tape recorder, muttered "the damn fuse," and rushed from the room. The S was then observed
for 30 minutes through a one-way screen. The lights and tape were then turned on again. The details of the
procedure are the same (with some important modifications) as those reported below for the present
study.
Six Ss were deeply hypnotized and six other Ss had been given standard simulating instructions (Orne,
1971). The E, of course, was unaware of S’s status and could not guess better than chance which Ss were
simulating and which were hypnotized.
The objective behavior of the simulating Ss in the first study is presented in Table 1. Five of the six
simulators continued to simulate hypnosis, keeping their eyes closed, tapping their feet to "hallucinated"
music, and keeping their arms on the chair. The reason for the continuation of the simulating behavior
throughout this period was most likely that they expected that E would try to trick them in order to detect
simulation. They later reported to the nonblind E (who had originally given the simulation instructions)
that they actually did suspect deception and that they did not feel the power failure was genuine.
Once it became clear that the manipulation was not successful, the procedure was examined with more
care. Three distinct factors in this situation seemed to make the deception less than adequate: (a) In order
to facilitate observation, all experimental rooms had conspicuous one-way screens. Since all Ss had
completed several hypnosis experiments in the same room, it was hoped that Ss would have become
sufficiently adapted not to notice them. (b) When the "power failure" occurred, a bright desk lamp, which
was plugged into the same wall socket as the tape recorder, went off simultaneously with the tape
recorder. The overhead ceiling light stayed on, however, partly because it facilitated visual observation
through the one-way screen. (c) In addition to the tape recorder, a small two-channel Offner polygraph
283 THE DISAPPEARING HYPNOTIST
was situated in the experimental room. It was plugged into a wall socket at the other side of the room and
did not stop recording when the power failure occurred. A high hum is always associated with the
polygraph; its continued functioning would have been obvious to Ss even with their eyes closed. Since it is
quite common for a fuse to blow on one circuit while another circuit in the same room continues to
function (and since physiological data for Ss during the breakdown period were also desired), we had
hoped that the situation would be plausible despite the continued functioning of the polygraph and the
overhead lights.
It should be emphasized that these flaws in the experimental procedure, so blatant and obvious in
retrospect, represent the kind of procedural detail which is hardly ever reported in print, nor did they
appear particularly meaningful prior to the completion of the first study. Only when the situation failed to
deceive the simulating Ss did we consider these design problems. Inadequacies of the procedure identified
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by the simulators' behavior were also corroborated by the comments made later by the simulating Ss
during the post-experimental discussion.
The behavioral evidence convinced us that the design of the study had been inadequate. Highly motivated
and suspicious simulating Ss had not been convinced that the power failure was an accident.
Consequently, it was not possible to draw clear inferences about the behavior of the (presumably less
suspicious) hypnotized Ss. It was most parsimonious to assume that they, too, could have suspected the
power failure was not an accident, but rather a ruse of E. Given this possibility, the experiment would not
have been testing the effects of a sudden termination of hypnosis, but rather only Ss' ability to second
guess E’s ruses -- a trivial finding in this context. The only feasible conclusion
284 EVANS AND ORNE
was that a valid operational procedure for testing the experimental hypothesis had not been successfully
executed.
The present study was an attempt to modify the procedure in important ways so that a viable experimental
procedure could be established. The role of simulating Ss was to provide objective evidence about
whether the experimental situation convinced motivated, suspicious Ss that the power failure which
occurred was indeed accidental.
PROCEDURE
Subjects
The Ss were selected from a large population of college undergraduates who had volunteered initially to
participate in hypnosis research. They had completed at least the Harvard Group Scale of Hypnotic
Susceptibility, Form A (HGSHS:A) of Shor and E. Orne (1962) and the Stanford Hypnotic Susceptibility
Scale, Form C (SHSS:C) of Weitzenhoffer and Hilgard (1962). After qualifying with extreme scores
(upper and lower five percent of the score distributions) on these scales, Ss were clinically evaluated at
least twice on the diagnostic rating scale measuring hypnotic depth described by Orne and O'Connell
(1967). The Ss who still qualified at the end of this procedure were either deeply hypnotizable or
essentially insusceptible Ss.
In addition to the assessment of hypnotic susceptibility, Ss had participated in at least two experimental
hypnosis sessions in the room in which the reported study took place. During these sessions they became
acclimated to tape-recorded hypnotic induction procedures. The Ss were told that they were participating
in an extensive investigation measuring depth of hypnosis and interrelating several different methods of
assessment: standardized scales, objective behavioral tests, subjective impressions of depth of hypnosis
(recorded continuously by S on a circular hypnotic depth indicator, HDI), and physiological indices
(including galvanic skin potential, GSP). The Ss selected for the present study were scheduled for an
additional two sessions as part of this ongoing research, and insusceptible Ss received the simulation
instructions reported below. The physical setting and general procedures were the same in both sessions.
The accident occurred late in the last session.
Simulating subjects. The Ss chosen to simulate hypnosis had been completely unresponsive to hypnotic
effects in the previous sessions and were themselves convinced that they were insusceptible to hypnosis.
They had scored 4 or less on at least two standard scales and no higher than 2 in at least two diagnostic
sessions. Simulating Ss were given an accurate (and truthful) description of their task. In summary, each
simulator was told:
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Your task during the next two sessions is to try to fool another hypnotist by pretending to be deeply
hypnotized. Although you are not susceptible to hypnosis, your task is to pretend to be a deeply
hypnotized S, to fool another E who is a trained, expert hypnotist. The new E knows that some Ss will
really be hypnotized and that others will only be acting, but he does not know which Ss are hypnotized
and which ones are faking. In previous research it has been found that a "blind" E cannot with certainty
pick out which Ss are simulating. The task is not an easy one for you, but it can be done successfully. If E
becomes sure that you are actually simulating, however, he will stop the experiment and your services will
be no longer required. You should make use of whatever clues you glean from the instructions, the
experimental procedure, your past experiences with hypnosis, and your expectations and conceptions
about what deep hypnosis is like. Your task is even more difficult in this study, because you have to
simulate with the hypnotic depth indicator and the physiological record at all times; one of the important
aims of the experiment is to determine whether you can fool the machine, as well as the hypnotist. Good
luck!
Hypnotizable subjects. The six deeply hypnotizable Ss in each study could experience all major
phenomena of deep hypnosis, with marked subjective conviction about the reality of their experiences. All
Ss could experience challenge suggestions, positive and negative hallucinations, complete posthypnotic
amnesia, and would carry out posthypnotic suggestions compulsively. They had scored 8 or more on
HGSHS:A and SHSS:C and in the 5-range of the diagnostic scale. In accordance with the simulating model
(Orne, 1971), hypnotized Ss did not know that simulating Ss were participating in the study.
Experimental Session Procedure
As in the first of the two sessions, the experimental session commenced after the application of the
recording electrodes. Minimal interaction took place between the "blind" E-observer and S. As before, a
short passive hypnosis was induced to measure psychophysiological baselines. Hypnosis was induced a
second time, and S completed a memory experiment lasting about 30 minutes. During these periods the
"blind" E occasionally monitored the GSP recording in the room. The "blind" E then made a final
judgment about whether she believed S was hypnotized or simulating.
Hypnosis procedure before tape breakdown. The tape was started again and hypnosis was reinduced. Arm
levitation and arm rigidity suggestions were administered. Emphatic suggestions were given that S’s right
hand and arm were stuck tightly to the table and arm of the chair and that they would remain stuck until E
said, posthypnotically: "Your arm is comfortable now." After S tested that his arm was stuck, by trying to
lift it, suggestions were given that he was at a concert
286 EVANS AND ORNE
listening to his favorite music, tapping his foot in time with the music. "... You're enjoying it [the concert]
so very much that you hum the tune to yourself, that you tap in rhythm to the music. You go on tapping*
your foot. Keep on tapping your foot in rhythm with the music." At the predetermined point during this
suggestion (marked by the asterisk above), the power failure was made to occur.
The power failure. The tape recorder was plugged into a hidden extension cord which led behind a large
Ampex tape console into the adjacent observation room. A silent mercury-switch was thrown in the
observation room, stopping the tape recording in mid-sentence with a marked slur. Simultaneously, the
desk light turned off and the overhead lights went out. The larger "computer" recorder and table
polygraph both stopped. Immediately the "blind" E sprang up, switched the light twice, manipulated the
control dials of the tape recorder console, and after muttering softly "the damn fuse," she hurriedly left the
room, slamming the office door. She then quietly entered the adjacent observation room.
The S was observed for 40 minutes from the time the light went off. After 40 minutes the electrical power
was switched on again. The lights flashed on instantaneously. The tape recorder started turning, but took a
few seconds to warm up before the sound recommenced. The tape restarted at exactly the same point as it
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had stopped. Thus, the suggestion about the concert continued where it had left off 40 minutes earlier.
Two and one-quarter minutes after restarting the tape, the "blind" E quickly re-entered the room,
appearing slightly disheveled. If S still had his eyes closed, E said nothing. If S was not apparently
hypnotized at this point, E re-induced hypnosis by counting from 1 to 20, the standard cue previously
used.
The tape continued to the end of the suggestion about the concert and several additional suggestions were
administered. Hypnosis was terminated, and, after amnesia was tested, a brief inquiry was conducted by
the "blind" E, during which S was asked what he thought had been the purpose of the experiment. If S
mentioned the power failure, E said that a fuse had blown, but further discussion about the tape
breakdown was avoided as much as possible. The "blind" E removed the posthypnotic suggestion that S's
arm was stuck to the chair and then left to find the "non-blind" E. A more exhaustive inquiry about S's
perception of the meaning of the experiment and the nature of his subjective experiences was conducted.
Procedural Differences from the Original Unsuccessful Study
Several important changes were made in the replication study procedure which, it was hoped, would
eliminate some of the cues that indi-
287 THE DISAPPEARING HYPNOTIST
cated to the simulators in the earlier study that the power failure was, in fact, part of the experiment. With
these changes, it was hoped that the power failure was perceived as a genuine accident.
A variety of psychophysiological measures were recorded on an Offner Type R polygraph. Standard
recording techniques were used. These included occipital and parietal monopolar EEG, horizontal eye
movements, GSR, GSP, respiration, and EMG leg activity. The recording electrodes were led into the
observation room but by a route not visible to S. The Ss were told that their responses would be played
directly into a large Ampex tape recorder for subsequent computer analyses. The tape deck (which
blocked the corner of the room where the leads entered the observation room) was started, but actually
recorded nothing. In addition, a small two-channel Stoelting polygraph was in the experimental room. In
the previous study, a similar small machine was used. One channel recorded respiration, the other was
used to provide necessary coded signals between the experimental and observation rooms for the standard
on-line monitoring of the physiological data. 8 As in the previous study, the Stoelting recording was visible
to the S, and E periodically examined it. Following the power failure, the cessation of these recording
devices presumably added to the plausibility of the deception, because nothing was apparently being
recorded.
Instead of the one-way screen, an old but relatively unknown method of observation was adopted.
Hanging on the walls of the experimental room were three framed silk screen paintings that fitted into the
natural decor of the room. One of the paintings covered a hole in the wall. Silk screen acts like a one-way
screen when looking from the dark to the lighter side. 9
When the "power failure" occurred, not only did the tape recorder slur to a halt, but the Stoelting and
Ampex equipment also stopped, and all lights in the room went out. These occurrences were intended to
help convince S that not even his physiological responses were being recorded. Thus, the power failure
affected all the equipment in the room rather than just selected parts of it, as in the earlier study. When E
left the room, even the hallway lights were off. During daytime sessions, a small amount of daylight
passed through the drapes. At night, only dim
8 As there are no consistent differences which indicate the presence of hypnosis on standard
psychophysiological measures, these data will not be reported. They were added primarily to provide
emphasis for S that continuous recordings were being taken and to provide additional physical restraint
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during the session. Hopefully, the electrodes added to the plausibility of the study.
9 In fact, this was the system employed in the original one-way observation room at the Harvard
Psychological Clinic prior to the development of one-way glass.
288 EVANS AND ORNE
light entered from a distant parking lot light that had been specially and strategically installed for
observational purposes. Further, a female medical student was chosen as the blind E in the replication
study. It was hoped her ingenuousness and confused reaction to the fuse problem would be credible,
making it less likely that Ss would feel they were being deceived when a power failure apparently
occurred.
RESULTS
Simulating subjects. In the earlier study simulating Ss continued to pretend they were hypnotized
throughout the 30-minute observation period. These performances provided objective evidence that they
perceived the accidental power failure as part of the experimental procedure, thereby invalidating the
experiment. This time, simulating Ss performed quite differently compared to simulators in the earlier
study. Here, five of the six simulators immediately ceased simulating when the observer left the room.
They opened their eyes within seconds after she closed the door. They remained active and alert for the
full 40 minutes of observation. When the tape was recommenced, simulators immediately resumed
simulating as the observer's footsteps approached the door. On each of the three objective criteria -- time
to open eyes, cease tapping, and move the stuck arm (see Table 2) -- mean performance time for the
simulators was significantly shorter (p < .01, p < .02, p < .05, respectively) in the present study than in the
earlier one.
Two conclusions are suggested by the behavior of the simulators, both of which were confirmed in
post-experimental inquiries. (a) The plausibility of the accident was confirmed. Simulators believed a fuse
had truly blown and did not consider as a possibility that the accident was part of the experiment. They
perceived no need to continue faking
289 THE DISAPPEARING HYPNOTIST
during this period because it did not occur to them that they were being watched. This conclusion was
reinforced by the varieties of private behavior which simulating Ss would not have indulged in had they
believed they were being observed. (b) Simulators apparently believed that truly hypnotized Ss would not
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notice the power failure, and, as indicated by their return to simulation when the power was restored,
believed hypnotized Ss would remain hypnotized for more than 40 minutes.
Having successfully demonstrated that the simulators behaved as if they believed they were not being
observed --establishing by their behavior the plausibility of the accident -- we felt in a position to evaluate
the performance of the deeply hypnotized Ss. If highly motivated simulating Ss did not doubt the reality of
the accidental power failure, it seems unlikely that the hypnotized Ss with less reason to be suspicious
would seriously entertain any doubts about the veridicality of the procedure.
Hypnotized subjects. Deeply hypnotized Ss showed no immediate behavioral signs of being aware of the
power failure nor of E departing (see Table 2). Five of the six Ss remained passive for several minutes;
behaviorally, they looked exactly as they had before the power failure. Then, after a mean of 10.7
minutes, they ceased foot-tapping; they opened their eyes after 16.5 minutes; and, while looking around
the room, first moved their "stuck" arms after an average of 19.2 minutes. Their behavior was consistent
with the hypothesis that they would arouse themselves from hypnosis after a period of time (ranging from
1 to 29 minutes) following the departure of E. This sequence of events was confirmed by their subsequent
subjective reports. It appears that hypnosis is not limited in its duration by the immediate presence of the
hypnotist (observer) or of an immediate hypnotic surrogate, the tape-recorded procedure, nor does
hypnosis persist as long as other unhypnotized Ss believed it would.
Some Comparisons between the Two Studies
The dramatic difference in the performance of the simulating Ss in the two studies has been described.
Changes in the procedure that appeared relatively minor, but which actually involved a great deal of
planning and testing, led to a situation which was perceived entirely differently by the two simulating
groups. In the first study the behavior of the simulators indicated that the deception was transparent; in
the second, the behavior of the simulators indicated that no deception was suspected. No inference about
the behavior of the hypnotized S was possible in the first situation, because the procedure could have
been,
290 EVANS AND ORNE
for them, equally transparent; there is no experimental way of evaluating their real perceptions. In the
latter study, however, inferences can be drawn because the evidence indicated that the deception was
convincing enough to be accepted. Under these circumstances, it is all the more remarkable that the
performance of the hypnotized Ss in both studies was consistent and could not be differentiated
statistically. In both instances the hypnotized Ss behaved significantly differently from the simulating Ss -they did not remain hypnotized as long as the non-deceived simulators in the unsuccessful study, and they
remained hypnotized longer than the deceived simulating Ss in the second study. 10 This evidence
suggests that hypnotized Ss were not responding maximally to the cues inherent in the situation, but rather
were responding to those cues derived from their ongoing subjective experience.
In summary, the behavior of the hypnotized S is not consistent with the view that the cessation of the
ongoing relationship will instantaneously terminate hypnosis (as it did with the simulators who accepted
the accident in the second study). Nor is it consistent with the behavior of the simulators who, in the first
study, believed that the "accident" was faked and that they were being observed throughout. The
hypnotized Ss appeared to be initially unaffected by the accident, but, in accord with a feeling of
free-floating anxiety that "something had happened" (expressed later in post-experimental interviews),
were able to terminate hypnosis by themselves. This task was typically described by them as a difficult
one.
The Return of E
Of considerable interest is the behavior of both groups of Ss when the power was turned back on. About 2
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1/2 minutes after the tape recorder came back on, E could be heard walking down a corridor and then
entered the room. As soon as the lights were turned on, the simulating Ss (who had temporarily stopped
role playing) quickly resumed a position similar to the one occupied when E left, typically taking great
care to put the arm, which was supposed to be stuck to the arm of the chair, back again, and adjusting the
HDI (which several of them had randomly moved and played with in the interim). As they heard E
returning, and as the doorknob turned, they resumed tapping and closed their eyes. They clearly wished to
convey the impression that they were still hypnotized, providing additional evidence that they did not
seriously contemplate that they might have been observed during the preceding 40 minutes. In addition,
this behavior provides strong evi10 Using simulating Ss does not provide a control group in the classical sense, and traditional statistical
tests may not be appropriate. The results reported were significant using Fisher's exact test (p < .05).
291 THE DISAPPEARING HYPNOTIST
dence about a popular notion of what would happen if, in an actual situation, hypnosis was inadvertently
terminated by the absence of the hypnotist; clearly the simulating Ss believed a hypnotized person would
remain in trance for at least this length of time.
In contrast to the expectations communicated by the simulating S, the behavior of the hypnotizable Ss in
both studies was counterexpectational. Excluding the one S who did not terminate hypnosis, 10 of the 11
susceptible Ss in the two studies made no attempt to re-enter hypnosis when E returned. Rather, they
turned towards E with a puzzled look, sometimes with a nervous laugh, apparently seeking an explanation
of what had happened.
DISCUSSION
The experimental findings of the second study considered in conjunction with the previously reported
results (Orne & Evans, 1966) have important methodological and theoretical implications for hypnosis
research.
The Use of Simulating Ss to Test the Adequacy of an Experimental Deception
In this study the purpose of the simulating Ss was to provide a rigorous test of how S perceived what was
intended to appear to be a spontaneous power failure. Since simulators are instructed to mimic the
behavior of deeply hypnotized individuals without the benefit of specific task instructions, they are forced
to rely upon their previous knowledge about hypnosis and their analysis of the cues in the situation. These
individuals, therefore, would be particularly sensitive to subtle nuances in the behavior of the hypnotist
and even more so to subtle aspects of the experimental situation which might serve to communicate how
they ought to behave.
The two experiments taken together illustrate how the simulating Ss provide a conservative estimate of the
kind of cues made available by the total experimental procedure. In the first experiment the simulating
group was not deceived because sufficient care was not taken to solve the technical problems that are
involved in properly staging the power failure. Therefore, it was not appropriate to draw inferences about
the behavior of the deeply hypnotized group in that study. Although significant differences were found
between the behavior of the two groups, the behavior of the simulators showed that the deception was not
convincing. Because of the inadequacy of the manipulated deception, it could not be asserted, with any
degree of certainty, that
292 EVANS AND ORNE
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the power failure was perceived as genuine by the hypnotized group. In the second experiment, great care
was taken to assure the plausibility of the deception and, indeed, the behavior of the simulating Ss was
evidence that the power failure was seen as genuine. Because the simulating group now perceived the
experimental situation as it was intended -- the deception was successful -- we felt justified in assuming
that the behavior of the deeply hypnotized group permitted ecologically valid inferences to be drawn
about what would happen in a nonexperimental situation, were the hypnotist to actually disappear.
One very interesting observation deserves special comment. The hypnotized Ss in the first and second
studies behaved similarly. Not only does this observation challenge the view that hypnotized individuals
are particularly sensitive to subtle cues in a situation -- not surprisingly, a group of individuals asked to
deceive E are more alert to deception than the deeply hypnotized group -- but it also illustrates the
conservative nature of the simulating control group. In retrospect, the data suggest that the behavior of the
deeply hypnotized group may have been ecologically valid even in the first experiment. On the other
hand, we were not in a position to evaluate their behavior until the data from the second experiment
became available.
The purpose of the simulating control is to test the adequacy of an experimental procedure, and it will
sometimes provide a more rigorous test than is actually necessary. On the other hand, a control procedure
which forces the investigator to perfect his experimental procedure is highly desirable since it will
minimize the likelihood of generalizing inappropriately from laboratory findings. While further data will be
needed, the observations in these two studies, as well as the logical analysis of the situation, suggest that,
if a deception is not recognized as such by simulators, it is extremely unlikely to be recognized as such by
other Ss not given simulating instructions.
The use of simulators in this context is in some ways analogous to carrying out a test of significance. A
test of significance may turn out to be insignificant, leading the investigator to accept the null hypothesis
when it may not, in fact, be true. This is the price one must pay in order to minimize the probability of
accepting random fluctuations as significant differences. Similarly, when simulators see through a
deception, it becomes logically necessary to view the experimental procedure as inadequate for the "real"
group even though, as in this instance, this group did not necessarily see through the deception. The virtue
of the simulation group in a study such as this is to minimize the probability that the investigator will
delude himself about the effectiveness of a deception manipulation.
293 THE DISAPPEARING HYPNOTIST
Implicatiom of Behavior of Hypnotized Ss
Since it appears clear that the situation in the second experiment was perceived as an actual power failure
which happened to occur during an experiment, it is possible to infer how hypnotized Ss would respond if
the hypnotist had actually disappeared. Hypnotized Ss tended to arouse themselves from hypnosis after
some time had elapsed but in all cases well before the 40-minute period expired. For example, they
stopped tapping their feet after a mean of 10.7 minutes, and first opened their eyes, which were
supposedly tightly shut until after hypnosis had terminated, after a mean of 16.5 minutes. No S terminated
hypnosis as soon as E left the room, nor did any remain hypnotized for as long as the 40 minutes. Neither
the stopping of the tape recorder, the abrupt darkening of the room, nor the departure of the research
assistant, leaving S alone in the room, was sufficient to terminate hypnosis immediately.
Typically, the first sign that S was about to arouse himself was a movement of the hypnotic depth
indicator which often preceded other behavioral signs by several minutes. The Ss had received instructions
to move the depth indicator in accordance with how deeply hypnotized they were, and it is interesting that
the power failure did not deter them from continuing to follow the initial instructions they had received.
As Ss actually roused themselves, they appeared confused when they first opened their eyes, looking
aimlessly about the room. They subsequently reported during the inquiry with the original non-blind E that
they experienced a vague feeling that something had changed or was wrong, which gradually became
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more pronounced and made them somewhat uncomfortable, bringing them out of trance, until eventually
they no longer felt hypnotized. These subjective reports seemed highly concordant with their behavior,
which suggested that hypnotized Ss aroused themselves slowly with some difficulty.
In evaluating these findings it is important to keep in mind that hypnotized Ss were selected from a large
population for their ability to enter deep hypnosis. Their behavior, therefore, can only be generalized to
other Ss who manifest the traditional criteria of deep hypnosis. (All Ss were in the 5 range, according to
the specifications of Orne and O'Connell, 1967.) Certainly, phenomena of this kind demand Ss who have
the ability to respond to hypnosis and who are motivated to do so, factors which are at least as important
as the hypnotic induction procedure. There is little doubt that Ss who are not capable of entering very
deep hypnosis, but are "hypnotized" by being exposed to a trance induction procedure, would arouse
themselves almost immediately
294 EVANS AND ORNE
when the power failure occurred. The question to which we have addressed ourselves in this research is
the extent to which deep hypnosis, the phenomenon classically described as artificial somnambulism, can
or cannot be explained exclusively as a consequence of S's motivation and expectations about how to
enact the role of a hypnotized individual. While the importance of these factors is recognized by the
authors (see Orne, 1959, 1970; Evans, 1968), this experiment was designed to see whether these factors
are sufficient to account for deep hypnosis.
The Counterexpectational Nature of These Findings
The behavior of the simulating Ss permitted inferences to be drawn concerning Ss' expectations about
what deeply hypnotized individuals would do if the hypnotist actually disappeared. In the first study, the
simulators, who recognized that the power failure was a deception, continued to act as if they were
hypnotized for the entire 30-minute period. In the second study, in which the power failure was more
realistically contrived, simulators stopped simulating as soon as they believed themselves to be alone.
When they heard E coming down the hall, however, they quickly assumed the appropriate simulated
hypnotic behavior, making certain that they appeared to be simulating hypnosis as E re-entered the room.
It is clear from the behavior of the simulators in both the first and second studies that Ss believe the
appropriate behavior of hypnotized individuals would be to remain in trance for a considerable period of
time after the disappearance of the hypnotist -- certainly more than 30 to 40 minutes. The deeply
hypnotized Ss behaved contrary to these expectations and beliefs. The hypnotized Ss terminated trance
during the observation period and, of course, did not make any pretense of being hypnotized when E
returned. If deeply hypnotized Ss are merely enacting a role, they certainly do not see their role as ending
immediately with the hypnotist's departure; in other words, if hypnosis is only role enactment, the role is
not audience-dependent in the usual sense of the word "role."
Usually it is difficult to determine whether the hypnotized S's behavior can be ascribed to hypnosis or
whether it might equally well and more parsimoniously be understood as S's responding according to his
expectations of how deeply hypnotized individuals ought to behave. In this experiment, however, the
behavior of the deeply hypnotized S cannot be explained as a function of either his prior expectations or
of the cues inherent in the experimental situation. Therefore it is difficult to see how the behavior of the
hypnotized Ss in this study can be
295 THE DISAPPEARING HYPNOTIST
explained solely as playing the role of a hypnotized individual. Rather, these data are more congruent with
the view that hypnosis involves some as yet unspecified alterations in the S's state of consciousness.
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REFERENCES
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DORCUS, R. M., BRINTNALL, A. D., & CASE, H. W. Control experiments and their relation to theories
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EVANS, F. J. The case of the disappearing hypnotist. Paper presented at the meeting of the American
Psychological Association, New York, September 1966.
EVANS, F. J. Recent trends in experimental hypnosis. Behav. Sci., 1968, 13, 477-487.
HILGARD, E. R. Hypnotic susceptibility. New York: Harcourt, Brace & World, 1965.
KUBIE, L. S., & MARGOLIN, S. The process of hypnotism and the nature of the hypnotic state. Amer. J.
Psychiat., 1944, 100, 611-622.
MILGRAM, S. Some conditions of obedience and disobedience to authority. Human Relat., 1965, 18,
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ORNE, M. T. The nature of hypnosis: Artifact and essence. J. abnorm. soc. Psychol., 1959, 58, 277-299.
ORNE, M. T. On the social psychology of the psychological experiment: With particular reference to
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ORNE, M. T. Hypnosis, motivation, and the ecological validity of the psychological experiment. In W. J.
Arnold & M. M. Page (Eds.), 1970 Nebraska symposium on motivation. Lincoln, Neb.: Univer. of
Nebraska Press, 1970. Pp. 187-265.
ORNE, M. T. The simulation of hypnosis: Why, how, and what it means. Int. J. clin. exp. Hypnosis, 1971,
19, 183-210.
ORNE, M. T. On the simulating subject as a quasi-control group in hypnotic research: What, why, and
how. In E. Fromm & R. E. Shor (Eds.), Current trends in hypnosis research. Chicago: Aldine, 1972, in
press.
ORNE, M. T., & EVANS, F. J. Social control in the psychological experiment: Anti-social behavior and
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ORNE, M. T., & EVANS, F. J. Inadvertent termination of hypnosis with hypnotized and simulating
subjects. Int. J. clin. exp. Hypnosis, 1966, 14, 61-78.
ORNE, M. T., & HOLLAND, C. H. On the ecological validity of laboratory deceptions. Int. J. Psychiat.,
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ORNE, M. T., & O'CONNELL, D. N. Diagnostic ratings of hypnotizability. Int. J. clin. exp. Hypnosis,
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SARBIN, T. R. Contributions to role-taking theory: I. Hypnotic behavior. Psychol. Rev., 1950, 57,
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SARBIN, T. R., & ANDERSEN, M. L. Role-theoretical analysis of hypnotic behavior. In J. E. Gordon
(Ed.), Handbook of clinical and experimental hypnosis. New York: Macmillan, 1967. Pp. 319-344.
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SHOR, R. E., & ORNE, E. C. Harvard Group Scale of Hypnotic Susceptibility, Form A. Palo Alto, Calif.:
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STRICKER, L. J. The true deceiver.Psychol. Bull., 1967, 68, 13-20.
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El Hipnotista Desaparecido Sobre como los Sujetos Simuladores y Realmente Hipnotizados
Perciben los Procedimientos Experimentales
Frederick J. Evans y Martin T. Orne
Resumen: Este trabajo examina los efectos producidos por una interrupcion de la corriente electrica en la
conducta de sujetos sometidos a hipnosis por medio de cinta magnetofonica; para ello era necesario que
esta interrupcion apareciera como casual y no como el resultados de un componente experimental como
se desprende de un estudio anterior (Orne & Evans, 1966). En ese estudio los sujetos simuladores
continuaron simulando el estar en hipnosis pues pensaron que la falla electrica era parte del experimento.
En este estudio dejaron de seguir simulando apenas el experimentador abandono la pieza creyendo que la
falla era real y no estaban siendo observados. En cambio los sujetos realmente hipnotizados salieron de su
estado lenta y gradualmente. Esta conducta no parece estar en relacion con aquellas teorias que suponen
que la hipnosis tiene que ver, o bien con motivacion, o bien con el desempeno de un rol.
Der verschwindende Hypnotiseur: Die Anwendung von simulierenden Vpn. zur Bestimmung der
Wahrnehmungen Yon experimentellen Verfahren in Versuchspersonen
Frederick J. Evans und Martin T. Orne
Abstrakt: Dies Studium untersucht die Effekte eines zeitweiligen Versagens des elektrischen Stroms in
einer Tonbandsitzung, wuhrend die Vp. hypnotisiert war. Es war notwendig, dass die Vp. das Versagen des
Stroms als einen Zufall und nicht als ein Hintergehen im Rahmen des Experiments auffasse. In einem
fruheren Studium (Orne und Evans, 1966) hatten Hypnose-simulierende Vpn. unter einem "blinden" Vl.
das Imitieren wuhrend des Stromversagens fortgesetzt, wahrscheinlich in der Annahme, dass sie unter
Beobachtung waren. Daher konnten keine Schlussfolgerungen uber das Benehmen der hypnotisierten
Vpn. gezogen werden. Nachdem man das Verfahren modifiziert hatte, horten die simulierenden Vpn. mit
dem Imitieren auf, sobald der Hypnotiseur den Raum verlassen hatte, womit sie ihren Glauben bewiesen,
dass ein Versagen des Stroms tatsachlich eintrat und auch dass sie nicht beobachtet wurden. Hypnotisierte
Vpn. beendeten selbst und spontan die Hypnose, obgleich langsam und mit subjektiver Schwierigkeit. Das
spontane Benehmen von hypnotisierten Vpn. bei der Abwesenheit eines Hypnotiseurs scheint nicht mit
den Voraussagungen in Einklang zu stehen, die auf motivierenden oder Rollespielenden Theorien der
Hypnose basiert sind.
The preceding paper is a reproduction of the following article (Evans, F. J., & Orne, M. T. The
disappearing hypnotist: The use of simulating subjects to evaluate how subjects perceive experimental
procedures. International Journal of Clinical and Experimental Hypnosis, 1971, 19, 277-296.). It is
reproduced here with the kind permission of the Editor-in-Chief of The International Journal of Clinical
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and Experimental Hypnosis.
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