Even though hypnosis has always been an enigma, it is still one of the seven wonders of psychology. As in the fable of the elephant touched in different places by the four blind men, each investigator has formulated a different theory. Therefore there are as many definitions of hypnosis as there are definers. Like the nature of human behavior, there will be different theories about hypnosis since all hypnotic phenomena have their counterpart in the various aspects of human behavior. Inasmuch as the latter is poorly understood, it is no wonder that hypnosis is difficult to understand. However, we shall try to explain hypnosis as objectively as possible.
Unfortunately, nearly all theories on hypnosis mistakenly attempt to explain the induction procedure, the interactions produced by the emotions, and the resultant hypnotic responses together. This is patently impossible, since they are separate and distinct entities which involve the hypnotist's and patient's subjective reporting. Not to recognize its dual nature is like including a surgical procedure and an anesthetic induction in a unified theory. The following review briefly covers the older and more recent theories on hypnosis.
ATAVISTIC HYPOTHESIS: IMMOBILIZATION THEORIES
Hypnosis has been considered to be an atavism that at one time may have been necessary in humans as a protective defense mechanism to ward off fear or danger.50 This theory was based on Pavlov's observation that an animal's only chance of survival is to remain immobile in order to escape detection.68 His theory is discussed more fully below. The atavistic hypothesis was reinstituted by Meares.62
As emphasized in the last chapter, hypnosis has been compared with the immobility reflex (I.R.) noted in animals when subjected to fear-producing conditions.45 Though induced differently in animals, the I.R. is produced chiefly by physical and instinctual factors. In humans it results from the interaction of these factors with the experiential meaning of symbols and words. Moreover, human and animal hypnoses are dissimilar in that repetitive induction in the animal decreases hypnotic susceptibility, whereas in humans it increases it.
In general, any powerful stimulus, such as fright, causes certain animals and humans to “freeze up.” This concept led to the “death-feint” theory of hypnosis.77 However, this theory does not explain how hypnosis occurs in humans. Similarly, hypnosis has been defined as “a state of readiness for emotional action increasingly subordinated to cortical influence as one ascends phylogeny, but nonetheless consistently present in animal organisms in a variety of forms.”33
HYPNOSIS AS A STATE OF HYSTERIA
At one time, hypnosis was considered to be a symptom of hysteria; only hysterical individuals were believed to be hypnotizable.13 This conclusion was drawn by Charcot on the basis of only a few cases in a pathologic setting. Such an hypothesis is untenable, inasmuch as susceptibility to hypnosis is not pathogonomonic of neurosis: normal individuals, in fact, are readily hypnotizable.10 Although hysterics are more suggestible than normal individuals, it does not necessarily follow that increased suggestibility is a sign of hysteria.
PSYCHOPHYSIOLOGICAL THEORIES
Some investigators implicate the reticular formation, 1,16,73 the hippocampus,15 and subcortical structures mediating communication.7 Others give similar explanations.8,75,100 Still other theories involve inhibition of the ganglion cells of the brain,35 inhibition and excitation of neurons,103 a focus of central excitation with surrounding areas of non-excitation,52 cerebral anemia,34 shift of nervous energies of the central nervous system to the vasomotor system,60 and vasomotor decerebration involving anemia of the frontal lobes.93 “Synaptic ablation,” wherein neural impulses are directed into a smaller number of channels (selective attention), has also been considered.21
Psychophysiologic data are lacking to substantiate any of these theories, particularly those that posit that anemia of the brain or a shift of nervous impulses accounts for hypnosis. If hypnosis is due to a shift of one set of neural functions, what produces it? If it is due to anemia, then anemic individuals should be readily hypnotizable. Finally, if the cerebral blood flow is decreased during hypnosis, fainting rather than somnambulism should be produced.61 More speculative formulations contend that hypnosis is due to psychophysiologic factors,75,100 psychokinetic field forces, and oscillating electromagnetic fields.64
HYPNOSIS AS A CONDITIONED PROCESS LEADING TO SLEEP
Pavlov believed that hypnosis was a “partial sleep.”68,71 In his classification, those stimuli directly affecting the sense organs constitute the primary signaling system of both men and animals. Symbols or words belong to the secondary signaling system and are characteristic for man alone. They exert their conditioned effects via the primary signaling system. Thus words act as conditioned stimuli, which may in turn produce physiologic reactions.17 A word (signal or cue) becomes the stimulus for conditioned reflexes which become involuntary for life. Pavlov observed that various gradations of hypnosis hardly differed physiologically from the wakeful state and that the fluctuating nature of hypnosis depended on insignificant variations of environmental stimuli. He hinted prophetically that lower brain stem mechanisms were involved in hypnotic conditioning. Some modern researchers continue to subscribe to the Pavlovian theory.41,47,94 However, most authorities do not believe that there is any similarity between sleep and hypnosis. If there were, it would be better to start an induction procedure with the individual asleep! Even though some investigators have been able to convert light sleep to hypnosis,8 this does not prove that the two are identical. Hypnosis is not a transitional state between sleeping and waking. Experimental data show a rapid decrement in motor response and reflexes during sleep. During deep sleep, conditioned reflexes or physiologic responses to a repeatedly given stimulus cannot be established, whereas in hypnosis the learning of conditioned reflexes is enhanced over and above that of the nonhypnotic state.
During normal sleep, suggestibility is decreased markedly, rapport is lost, and memories are eliminated. The whole concept of sleep, when applied to hypnosis, obscures rather than clarifies the issues. The subject appears to be asleep because eye closure usually is part of the induction procedure. Moreover, there is a considerable body of literature on blood pressure, reflexes, and physiochemical and EEG studies which indicates that hypnosis more closely resembles complete wakefulness.17,53,58
A hypnotized person is more alert to his environment than when he is asleep.46 However, if the operator uses a technic which emphasizes sleep, then the individual, because he responds experientially to the word “sleep,” is apt to enter into a sleeplike state. Thus, in such persons, the EEG findings might resemble those associated with sleep.81 On the other hand, for the same reasons, an entirely different result is obtained when the word “sleep” is not used. This was borne out by recent studies which showed that the behavioral characteristics which resemble sleep are not intrinsic phenomena of the hypnotic state.48
IDEOMOTOR ACTIVITY AND INHIBITION THEORY
It is contended by several authors that the effects of suggestibility are the result of ideomotor action and inhibition,2,26 and that suggestibility is merely an experience of imagining that which is actualized through ideomotor activities.2 Although this theory accounts, to a degree, for physical reactions and even for some of the psychological reactions noted during hypnosis, it fails to explain the complex psychological reactions elicited during hypnosis.
THE DISSOCIATION AND NEODISSOCIATION THEORIES
For many years it was contended that the hypnotized individual was in a dissociated state: certain areas of behavior were split off from the main stream of awareness.72 Accordingly, hypnosis abolished volitional control, and, as a result, the individual responded only with autonomic behavior on a reflex level. If the dissociation theory were valid, then amnesia could not be removed by the suggestions of the operator. Furthermore, the amnesia would always occur spontaneously.
Hypnosis has been described as “dissociation of awareness from the majority of sensory and even strictly neural events taking place.”96 While this is partially true, it does not help us to understand the actual nature of hypnosis. Dissociation characterizes not only hypnosis, but also many other altered states of consciousness, such as dreams, hypnagogic states, “highway hypnosis,” reverie states, the detachment or depersonalization seen in many types of religious worship, and many other mental phenomena.
This older theory fell into disrepute when it was demonstrated that more often, instead of amnesia or dissociation, there was a hyperacuity and a better coordination of all the senses during hypnosis. Thus, although some degree of dissociation occurs when amnesia is present, it by no means indicates that dissociation produces hypnosis or is similar to it.
Hilgard found Janet's dissociation theory interesting, and postulated the neodissociation theory.38 Although the theory is not finalized, Hilgard points out that the normal ego controls that take care of our needs allow socially acceptable behaviors and sensible choices. However, he notes that other processes are carried on outside of such normal controls, which, on occasion, can function simultaneously with them.
ALTERED STATE OF CONSCIOUSNESS THEORY
More recently, numerous writers have attempted to explain hypnosis by an altered state of consciousness (A.S.C.) paradigm which borrows heavily from Eastern philosophy.56,90,95Unquestionably, all such altered states are related, particularly the various types of meditative states such as transcendental meditation (T.M.) and the relaxation response, to be discussed in Chapter 27. These states allow greater preoccupation with internal sensations or mental processes. The relevance of A.S.C. for experiencing hypnosis independently and voluntarily sheds little light on what constitutes the hypnotic state. However, because a considerable body of literature exists, these shall be discussed in Chapter 27.
HYPNOSIS AS A STATE
Several authorities lean toward the idea of hypnosis as a state or “trance.”22,37,67 Most investigators, including the author, acknowledge the existence of hypnotic state. Hypnosis has been related to an “ability component” or a “trait of hypnotic responsiveness,” wherein its fluctuating responsiveness is recognized.37
To separate responsiveness to the hypnotist's demands from the kinds of behavior clearly associated with the state of hypnosis, Orne ingeniously compared a group of highly responsive subjects (“reals”) with a group of insusceptible subjects instructed to behave as they thought a deeply hypnotized subject would (“instructed simulators”).67 The “reals” demonstrated higher tolerance to pain, performed posthypnotic acts more readily, and were dehypnotized more slowly. Evans and Orne also showed that “reals” came out slowly, whereas the “instructed simulators” terminated rapidly after it was suggested that a “power failure” had occurred in the building.25 Sheehan had noted similar differences between hypnotic and simulating subjects.82 It has been argued that the relationship of simulator model to attribution theory (i.e., the subject's awareness of situational influences on his behavior) shows that hypnosis is a definitive state.12
In an earlier and elegant study, Orne differentiated the genuinely hypnotized subject from the hypnotic simulator by the phenomenon of “trance logic”—a unique, subjective experience characterized by a logical incongruity where the deeply hypnotized subject “buys things that do not add up.” Moreover, he observed that hypnotized persons have no difficulty seeing a hallucinated person and the real person simultaneously, whereas the simulator does not “buy” this incongruity; either the real image or the hallucination disappears. These observations were recently replicated.59 Thus it is highly presumptive to assume that hypnosis is a distinct state.
Orne also believes that sociocultural factors and the kind of experimental procedures employed play an important role in the behavior of the hypnotized subject.66 He contends that subjects receive precise though indirect cues on how to behave in the presence of environmental expectations that a specific behavior will or will not occur. Every situation shapes expected responses and makes contrary responses more improbable. Orne has named these aspects of an experimental situation its “demand characteristics.” In exploring these, he has not only shed light on the theoretical basis of hypnosis, but also on the social psychology of the psychological experiment. Orne's view is that if we are to identify the essential core of the psychotherapeutic process, we must isolate it from sociocultural aspects and “demand characteristics.”
THE ROLE-PLAYING AND NON-STATE THEORIES
One theory holds that hypnosis is due to goal-oriented striving at an unconscious level.101 Before Hilgard formulated his neodissociation theory, he postulated a developmental-interactive one.36 His thesis was that the subject's ability to assume a role and relinquish reality orientation depends on the way he interacts on an interpersonal level with the therapist. Here one would have to consider the importance of rapport. Some theories of hypnotic behavior stress social and interpersonal relationships, while others maintain that the subject plays a role, that is, he acts in the manner in which he believes a hypnotized person would act.77,78,79,83
Esdaile, who had such remarkable success with hypnoanesthesia, once made these particularly cogent remarks in relation to simulation and roleplaying:20
I see two ways only of accounting for it. My patients, on returning home, either say to their friends, similarly afflicted, ‘what a soft man the doctor is! He cut me to pieces for 20 minutes and I made him believe that I did not feel it. Isn't it a capital joke? Do go and play him the same trick,’ or they may say to their brother sufferers, ‘Look at me;
I have got rid of my burden’—20, 30, 40, 50, 60 or 80 lb., as it may be (scrotal tumors)—‘I am restored to the use of my body and can work for my bread. This, I assure you, the doctor did when I was asleep, and I knew nothing about it.’
Thompson states that she finds it difficult to believe that a simulator could undergo an abdominal operation without an anesthetic.88 Pearson holds similar views.69 The author emphatically agrees on the basis of a large number of surgical and obstetrical operations which he performed on hypnotized patients.
Barber, a non-state theorist, raises serious doubts about the conceptual usefulness of hypnosis.5 He argues that hypnosis is not a “state” or a “trance” and is not produced as the result of “suggestion,” but rather, that it is based upon a number of overlapping antecedent, intervening, and dependent variables. Barber also stresses an interpersonal relationship [belief and faith] in which the operator restructures the “perceptions” and the “conceptions” [imagination] of the subject, because the subject is relatively inattentive to his environment [misdirection of attention]. This results because the subject [due to an expectant attitude] is ready, willing, and able literally to think as the operator wants him to think. Such “perceptual-cognitive restructuring,” rather than “suggestion,” is the essential element responsible for hypnosis.
The role-playing theorists are not denying that hypnosis exists, but rather that all hypnotic behavior can be accounted for by the aforementioned variables, particularly the importance of motivation and the goal-directed imagination.6 They also claim that what can be done in hypnosis can be achieved by “training in human potentials.”6 This has been refuted by others.14,23,24,39 Hypnosis adds more than suggestibility per se, even though the state may involve some degree of role-playing. The author believes that it is the conviction that an altered state has been produced which results in some transcendence of normal capacities.
If hypnosis were due solely to role-playing, then psychoneurotics would ordinarily make the best subjects. Multiple personalities, who are not actors, readily switch from one role to another. The greatest thespian would be ashamed by the facility with which this is accomplished during hypnosis.
THE REGRESSION THEORY: PSYCHOANALYTIC CONCEPTS
A synthesis between psychoanalytical and Pavlovian physiological theories was attempted by Kubie and Margolin.52 These investigators felt that the subject undergoes an infantile regression, with the hypnotist fulfilling the role formerly played by the parents.27 Gill and Brenman have utilized this hypothesis, contending that “hypnosis was a regression in the service of the ego.”29For Gill and Brenman, transference (the transfer by the patient to the operator of emotions felt for some other person) is an important element of hypnosis. For Kubie, it is only a secondary phenomenon which may or may not be present.51 To him there is no specific psychophysiological setting in which the hypnotic process takes place. Kubie believes motivation to be more significant than the regression concept in understanding hypnotic response. Hodge stresses the contractual aspects of hypnosis.40 As an illustration of the concept of greater compliance, experimental data derived from volunteers, especially college students, differ from those obtained from clinical patients; the latter are more highly motivated.
An ego-psychological theory of hypnosis is seen as a special type of self-excluding function of the ego. A change occurs from conscious perception to preconscious functioning, akin to the performance of routine activities, and this is regarded as a “topological regression.”9 This hypothesis presaged the notions that subcortical functions played the important role in production of hypnotic phenomena. Fromm speaks of ego passivity or ego activity to describe various states induced during hypnosis.28 Each is differentiated from its external behavioral counterpart.
Hypnosis has been attributed to the patient's nonrational submission and relative abandonment of executive control to a more or less regressed, dissociated state.88 Ostensibly, the hypnotist shapes the regressed state to make it easier to achieve desired goals. These assumptions, however, have not been borne out by recent observations.54
A logical theory has been proposed by Gindes, wherein the proper motivation induces a favorable mental set (elimination or reduction of irrelevant stimuli) or readiness to comply.30 When this is combined with relaxation, concentration, belief, and expectation—all catalyzed by the imagination—hypnosis ensues. The sensory changes or the phenomena become effective through distortion of the imaginative processes. Such a theory makes the “Svengali-Rasputin” trance concept of hypnosis untenable. More psychoanalysts would use hypnosis if this concept of the omnipotent hypnotist were invalidated.
Theoretically, the child who had a domineering father should be hypnotized easily by an authoritarian approach. Proponents of these theories are unable to correlate either the depth or successful incidence of hypnotic induction with the supposed parent-child relationship. Furthermore, if these things were valid, men would be much better hypnotists than women. Experimental data indicate little difference;98a good subject is hypnotizable by either a male or a female operator. Moreover, the regression and transference theories cannot account for autohypnosis and those spontaneous alterations in awareness which simulate hypnosis.
However, even though hypnosis in certain instances might involve transference phenomena, they are very likely only incidental to it. Shor added the concept of transference to his dual factor theory, in which role-taking and generalized reality orientation fade into nonfunctional unawareness.84 Transference, when it occurs, is the result and not the cause of the hypnotic state.52 It is probably facilitated by the intense interpersonal relationship or rapport, rather than by a “plunge” into regression and dissociation.86,88 This concept may apply to the somnambulistic state but certainly not to light and medium stages. A more likely interpretation would involve the concept of a “transference readiness.”57,63
There are many combinations of the transference theories that have just been described. Some stress fascination or sensual attraction as an important factor; others consider that hypnosis is due to erotic elements in the doctor-patient relationship. If there is anything to these theories, then a necessary prerequisite for successful hypnosis would be fascination or sensual attraction. If it were true, all lovers would swoon into mutual hypnosis! The sensual attraction theory thus cannot serve as a generalization for the hypnotic state or hypnotic relationship.57
THE HYPERSUGGESTIBILITY THEORY
The theory of hypersuggestibility has enjoyed a certain popularity.3,43 According to its proponents, the subject's attention span is narrowed to the words of the hypnotist, and the latter's voice takes over the inner voice of the subject. This only explains the phenomenon and not how hypersuggestibility actually occurs. It does not explain the spontaneous occurrence of amnesia or other bizarre, nonsuggested symptoms such as hallucinations. The hypersuggestibility theory, by inference, also implies that only gullible people are suggestible. This is not the case. As proof, the influence of demagogues on mob psychology and the persuasive effect of orators and salesmen have been compared with hypnosis. Although strong persuasion is one factor for successful salesmanship, salesmen do not produce somnambulism, actual hallucinations, or anesthesia.
PSYCHOSOMATIC THEORIES
An elaborate theory hypothesizes that suggestibility is ideomotor action, which, in itself, is a form of abstract conditioning.96 Other investigators do not concur with the concepts of “abstract conditioning,”31 and the idea of stimulus-response notions as an explanation for hypnotic behavior has received little support.18
Weitzenhoffer97 notes that Wolpe's reciprocal inhibition is similar to a hypnotic induction technic: the desensitization procedures used in behavior modification are closely related to the “reconditioning” proposed by Wolberg.102
INFORMATIONAL THEORY
It is possible to advance a speculative hypothesis based on “brain-computer” analogies. Pursuant to this idea, it is important to note that the manner in which the central nervous system utilizes sensory processing and control of information can be studied in three ways: (1) by attempting to observe physiological events, such as electrical and chemical reactions, or other information-conveying mechanisms and energy conversions that are involved in nervous system dynamics; (2) by studying behavior as it occurs spontaneously or during experimentally designed situations; and (3) by attempting to develop physical models which retain certain essential characteristics of sensory processing of information and control at nonhypnotic and hypnotic levels. These three approaches may be labeled microscopic (the examination of detailed events in the CNS), macroscopic (the examination of behavior), and physical (the correlation with physical models of CNS control processes).
Since the first two approaches have been extensively described in relation to information processing, the emphasis of this discussion will be on the third approach—the physical model. This model is not to be confused with mathematical analogues of neurobehavioral functioning. Rather, it compares the evolutionary neurophysiologic development of the complex controls built into the human system design for self-regulation of homeostatic or adaptive mechanisms with those utilized by systems engineers for electronic high-speed “thinking machines.”49
Engineers are well aware that whenever a system adjusts its feedback networks to increase the signal to noise ratio, it is functioning optimally—in dynamic equilibrium or negative feedback. This “steady state” has been called everything from hypnosis, Nirvana, Zazen, and exaltation to union with God.
The processing, storage, and retrieval of information in hypnosis can be understood better from the study of brain-machine (computer) analogies. This is not to imply that the brain is a computer, but rather that scientists must conceptualize that the brain functions according to the same principles set down by the physical sciences for the design of communication equipment. Thus greater receptivity in a receptor (the subject) enables messages (sensory inputs or percepts), to be received clearly from a transmitter (the operator) with a minimal degree of interference (noise), either in the external environmental communication pathways (channel), or in the internal receptors of the subject. This enhances the transmission of reception of signals. For a more complete exposition of the informational hypothesis on how hypnosis represents a “regression” from functioning like a general purpose computer (G.P.C.) to that of a special purpose computer (S.P.C.), the reader can refer to Chapter 32.
SUMMARY
Most of the foregoing theories, even though inadequate in many respects, contain some facet of truth. However, hypnosis cannot be explained by any single factor (e.g., cortical inhibition, hypersuggestibility, atavism, regression, death-feint, dissociation, drive, goal-striving, role-playing, regression, or transference) because, like any behavioral process, it cross-fertilizes with many areas of human thinking. A complete theory of hypnosis is not available to gain wide acceptance. Moreover, many psychological and physical factors, acting reciprocally through the imaginative processes, induce the perceptual response called hypnosis.
Hypnosis cannot be produced with greater frequency in individuals with passive, infantile needs; nor does a regression of the personality necessarily occur from the hypnosis per se. The dependency relationship is no more an essential feature of hypnosis than that present in all doctor-patient relationships, even at nonhypnotic levels.
Hypnosis, then, is not a sharply delineated state, but a process along the broad, fluctuating continuum of what is loosely referred to as awareness, depending, as it does, upon the degree of arousal or perceptivity. What is referred to as the hypnotic state must be differentiated from the hypnotic interpersonal relationship, even though the latter developed from the hypnosis. The capacity to enter into hypnosis is as natural a phenomenon as sleep, both presumably developed as phylogenetic adaptive response mechanisms.
During hypnosis, the excitatory cortical areas can be conditioned to remain selectively “awake” to specific sensory percepts (selective attention), while other cortical areas which are partially or completely inhibited prevent access to the stored or experiential data (selective inattention). In the presence of the proper mind-set, new conditioned responses can be “built in” the organism on the basis of new convictions compounded upon previously invoked beliefs (the ideomotor and ideosensory responses). Under these conditions, “unreality becomes reality,” and the “conviction of hypnosis leads to hypnosis,” as there is no other way to think.
The brain apparently functions similarly to a data processing apparatus, which, when unable to validate incoming information (sensory percepts) against stored data (memories, impressions), causes unreality to be interpreted as reality. More attention should be paid to the manner in which physical scientists describe events in the central nervous system. Perhaps a better model of what constitutes hypnosis will thereby be formulated.
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