What Is Hypnosis?
By Gérard V. Sunnen, M.D.
INTRODUCTION
We are witnessing a blossoming sophistication in the science of the mind and especially in the elucidation of how the psyche interrelates with the physical body. It is in this domain that hypnosis finds its rightful niche as a science that deals almost exclusively with mind/body interactions; for this reason, hypnosis has had a fascinating historical trajectory.
Historically, hypnotic phenomena have been interpreted in different ways through the tinted glass of each culture's ideology. In Grecian sleep temples, for example, hypnosis was seen as a sleep state facilitating communication with deities (Zilboorg, 1941); in Mesmer's time, it was conceptualized as an agitated condition stemming from the absorption of cosmic forces (Crabtree 1993).
Hypnotic phenomena are not easily measured or quantifiably grasped. They are neither countable bacterial colonies on an agar plate nor hypnotic phenomena capable of precise delineation, as would be a cardiac rhythm. To some extent, they can be measured by any one of many psychological tests gauging suggestibility, hypnotic susceptibility, or the aptitude for imagery (Balthazard 1993, Field 1965, Bowers 1986). These tests may be administered before or after hypnosis. Tests may also center upon physiological parameters expressed through the electroencephalogram (EEG) or the metabolism of cerebral pathways (Graffin 1995). However, the complexity factor in hypnosis resides in that its manifestations tend to be subjective as much as objective, expressing themselves in the context of the global person (Mott 1995).
THE EXPERIENCE OF HYPNOSIS
Although there is fairly good general agreement regarding the psychological and physiological phenomena elicited through hypnosis, rich controversies exist regarding the mechanisms by which they occur (Kirsh 1995).
Participants vary greatly in their experiences during hypnosis (Hilgard 1965, Freundlich 1974). Certain feelings stand out as commonly encountered, whereas others remain idiosyncratic or rare (Twenlow 1982). In clinical situations, some people exit from the hypnotic experience astonished to have felt a state of mind so vastly different from their normal waking state, whereas others talk as if nothing unusual had happened. In the former case, the vivid impact of the experience will serve to facilitate further hypnotic work through the subject's conviction that some tangible phenomenon has indeed taken place. In spite of any novel sensations in the latter case, individuals may, much to their surprise, be able to show a full range of hypnotic phenomena. For example, a severely overweight woman in her thirties, who had a long history of failed attempts at following dietary regimens, came out of her first hypnotic session disappointed. She imagined that she would have experienced a feeling of other-worldliness during trance, whereas in fact, she reported only a slightly enhanced level of relaxation. As treatment continued and suggestions were offered to follow a nutritional plan with ease, she expressed surprise. In spite of the absence of subjective changes during hypnotic sessions, she was able to actualize the message of the suggestions seemingly automatically.
During the deeper stages of hypnotic experience, participants may be asked to talk about or to notice how they feel. The answers are usually spoken in monotone, slowly, and with pauses. A query asked during hypnosis, even if not assiduously answered at the time, makes it easier for more detailed reports to be shared after hypnosis because some degree of observing self-awareness will have been kindled.
Physio-Motor Changes
During hypnosis the motions and the internal workings of the body often feel decelerated. There may be a sense of inertia or a feeling of not desiring to move; if movements are made, they have a tendency to be carried out less frequently, to have reduced range, and to be experienced internally as if made in slow motion. There is frequently a pervasive sensation of comfortable heaviness permeating the neuromusculature. This sensation, which goes hand-in-hand with physiological appeasement, may be looked for and suggested during the induction because its presence tends to convince the participant that some real internal change has indeed transpired.
One of the characteristics of hypnosis is physiological languor, but not all hypnotic phenomena occur in this context (Malort 1984). Although in medical hypnosis we tend to suggest to our patients a global relaxation response, there are hypnotic-like states in which activation rather than relaxation is a prominent feature (Fellows 1993). Certain states are sometimes elicited in the course of religious ceremonials, as is observed in Sufi dancing dervishes (Rouget 1980). In modern clinical practice, suggestions of physical action in the context of psychological relaxation are often utilized. It is possible, for example, to present posthypnotic suggestions for the purpose of enhancing athletic performance, which requires intense concentration and physical effort. The athlete, during trance, visualizes himself actualizing a performance with peak mastery. Once these images are incorporated into memory posthypnotically, they can exert a positive influence upon the performance itself (Liggett 1993, Stanton 1994).
Relaxation and Meditation
Relaxation has both physical and psychological components. Parallel with physiological parameters, the experience is one of repose and calm. Of all the hypnotic phenomena, relaxation is the most easily and consistently observed. In some individuals the relaxation can be extremely pronounced, and it is not infrequent for first-time participants of hypnosis to say that they have never before felt a relaxation level so profound.
This important global response is already present in neutral hypnosis (i.e., hypnosis without any overt suggestions or the phase of the hypnotic process following induction and preceding the presentation of suggestions) (Edmonston 1977). By adding proper suggestions, neutral hypnosis can be,amplified many times over. Once experienced by the patient, relaxation can, through the techniques of self-hypnosis (the process by which a trance is brought on by the participant himself) or posthypnotic suggestion, be applied during situations previously experienced as stressful or anxiogenic.
The feeling of relaxation in hypnosis can range from mild, general deceleration to pervasive peacefulness. In the latter instance, the parts of the mind that contribute to anxiety are quieted.
Physiological Changes Observed in Hypnosis
The literature contains many accounts of physiological changes associated with hypnosis (Sturgis 1990). It is important to note, however, that no physiological variable has been shown to be systematically or regularly associated with hypnosis (Sarbin 1972). Most experiments that purportedly show a correlative relationship to physiological variables fare equivocally on replication or are methodologically imperfect.
The physiological changes observed during hypnosis are greatly influenced by the nature of the suggestions administered. It stands to reason that incentives to relaxation will lead to a different physiological response configuration compared with suggestions centering upon activation in any one of its forms.
It is common to observe cardiac variability during the initial phase of hypnotic induction (DeBenedittis 1994), which may be due to feelings of novelty about the upcoming experience, especially if it is a first experience. This response is followed by a slowing regular rhythm as deeper stages of hypnosis are achieved (Harris 1993).
Reduced bleeding time has been reported in patients undergoing surgical procedures with the assistance of hypnoanesthesia (Bishay 1984). Vasodilation and increased circulation to otherwise poorly perfused areas have also been reported in response to hypoanesthesia instructions (Rossi 1997).
Longitudinal studies on blood pressure reduction through hypnosis have yielded erratic results, depending upon the research approach. However, by means of training in self-hypnosis (Deabler 1973) and especially with the integration of hypnosis with biofeedback support, hypertensive subjects have been able to modulate and even normalize their blood pressure readings (Friedman 1977).
A slowing of the breathing rate can be observed in individuals within the deeper dimensions of the hypnotic experience (Sarbin 1956). Breathing is then more likely to show less amplitude and to be more abdominally expressed. On the other hand, respiratory rate, predictably, is found to increase when cognitions of fear, anger, pain, or muscular activity are elicited (Dudley 1964).
A number of metabolic changes have been reported to take place following hypnotic suggestions. Among them are alterations in blood glucose level, basal metabolic rate, calcium metabolism, and oxygen saturation (Lovett-Doust 1953). There are also reports that the body temperature may be raised or lowered, depending upon the suggestion presented (Margolis 1983).
The hypnotic experience has been approached through many physiological channels, including gastric secretions (Klein 1989), cerebral blood flow (Diehl 1989), cerebral oxygen consumption (Malolo 1969), and electrodermal activity (Boucsein 1992).
Few endocrine studies have been performed. Release of adrenocorticotropic hormone (ACTH) by the pituitary gland can be affected directly by emotional stimuli, and some researchers have reported a drop in plasma cortisol titers to significantly low levels shortly after hypnotic induction (Sachar 1964). Cutaneous functions have occasionally shown marked sensitivity to hypnotic influence (Burgess 1996).
A Sudden change in brain voltage that is initiated by an external stimulus is referred to as an evoked potential (Davic-Jefdic 1993, Jutai 1993). Some experiments seem to show a diminution of visual evoked potentials in hypnosis (Banyai 1981).
Numerous studies have attempted to analyze EEG patterns in hypnosis (DePascalis 1993). Some researchers have found enhancement of theta rhythm after hypnotic induction (Tebecis 1975). EEG measurements comparing neutral hypnosis--which presumably would reflect the physiological essence of the hypnotic state because of the absence of administered suggestions--and the state of wakefulness have interested many researchers. Several studies have shown an augmentation of alpha wave density during hypnosis (Melzack 1975). Others have discovered EEG patterns in neutral hypnosis marked by enhanced delta and theta activity, with concomitant reduction of alpha and beta wave manifestation (Saletu 1987).
Despite the efforts of numerous researchers, the hypnotic condition has not yielded substantive physiological correspondence. Despite the growing sophistication of medical technology, much needs to be accomplished to correlate psychological dynamics with some yet elusive central nervous system alteration. We are nevertheless gently reminded of Freud's futuristic remark that every thought--and presumably every alteration in mental state, including hypnosis--will eventually prove to be accompanied by a specific neurophysiological event.
Anticipatory anxiety is a universal source of stress. Self-reproach, guilt, resentment, and dwelling negatively on the past are also sidestepped, as the mind is asked to confine itself to an experiential grounding in the very present time. There is a moving away from the perceived complexities of the current life situation into self-reflection. Some contemporary theoretical approaches suggest that the frontal lobes of the hypnotized individual act as if they have been distanced from the nervous system (Crawford 1994, Gruzelier 1993). In the construct of this rough neurophysiological model, the frontal lobes, in their psychological correlation with concerns about the past and worries about the future, may function as if they had assumed relative dormancy.
Relaxation is a complex global state involving not only physical and physiological realms but also dimensions touching upon the emotions and thought processes. It is hardly possible for an individual to be fully relaxed and physically at rest and at the same time emotionally disquieted by ruminative feelings, such as resentment or shame or by activated thoughts fueled by worry and unrest. Hypnosis in its relaxing action touches all dimensions of the body and the psyche. In this sense, it can be said that hypnosis is the most potent nonpharmacological relaxing agent known to science.
Descriptions of the subjective experience of the hypnotic trance often include alterations in the perception of time flow and sensations of relative removal from the ties connecting the individual to reality. Yet, during hypnosis, the individual may still feel, with varied intensity, the presence of the hypnotherapist, and with it, a sense of security and reassurance. In hypnosis, the elements of this relationship are closely intertwined with the experience of the trance because part of the patient's psyche is linked to the hypnotist's psyche in a process of dynamic communication, a dyadic alliance (Diamond 1984). The hypnotherapist may communicate with one part of the subject's self, then with another, but there remains an interpersonal bridge, regardless of the clinical approach of the hypnotist, which may be very permissive, choice-giving, and open-ended in the manner that suggestions are presented. Indeed, no matter what the style of the hypnotic process, the structure of the therapeutic relationship imbues its experience.
Self-hypnosis expands the privilege of autonomy (Garver 1984). The link of interpersonal rapport is dissolved as the experience becomes more fully intrapsychic. A more conscious portion of the mind gives suggestions, affirmations, and directives to another, more unconscious part (Sacerdote 1981). According to some authors, the autonomy accompanying self-hypnosis may invite disproportionate wanderings of attention and less task orientation than that observed in the more structured heterohypnosis (Fromm 1990).
Sometimes the individual enters a self-hypnotic state .and does not give himself specific suggestions, which may be called neutral self-hypnosis, a state marked by relaxation, free-floating imagery, and dream fragments or sequences. In neutral self-hypnosis, the sense of control floats, undirected. In this unstructured trance state, the subject may observe and remember or not observe and not remember.
If we add one ingredient to this self-induced trance state, we have meditation. That ingredient is focused watchfulness.
The meditative trance is similar in quality to the self-hypnotic experience. In meditation, however, the individual starts out with no overt induction process but rather with the resolve to begin and continue the experience and to direct the observing self toward a meditative focus (Sanders 1991). This point of convergence may be a part of the body (e.g., the solar plexus), an imagined or spoken sound (mantra). a meditative image (mandala), or a selected spiritual idea (Naranjo 1971). Meditative focusing is showing ever richer potential in harmonizing the mind/body related dysfunctions (Shapiro 1982).
Time Changes
In the experience of hypnosis, the sense of time is shifted from external to internal events. Consequently, the sensation of time passing is correspondingly stretched because internal events are subjectively slowed (Blakely 1991, Von Kirchenheim 1991). Time feels less insistently present, and it is not uncommon for a participant to estimate the duration of a hypnotic session to have been 30 minutes, when in fact it has been only a few minutes (St. Jean 1988). In other cases, time feels as if it has stood completely still, as if frozen.
Body Image Change
The experience of how the body feels during the normal waking state is often changed during hypnosis. With eyes closed, the waking subject, when asked to convey the configuration of the body as it is experienced, will usually describe a fairly anatomical rendition, with all the body parts in their respective positions. More precisely, the hornunculus in the brain, with its disproportionate emphasis upon head, eyes, and feet, will correspond to the imaginal rendition.
The experience of how the body feels during the normal waking state is often changed during hypnosis. Without directive suggestions, the body may feel heavy, as if pushing into the cushions of the chair; or the body may feel lighter, as if floating. At times the body will feel larger, expanded, and macroscopic, as if filling the entire room. Rarely, it may feel microscopic (Gill 1959, Freundlich 1974).
Changes in Thinking Processes
Along with physiological slowdown, the flow of thoughts is likely to show variability in its velocity and direction. In any given day or moment, the course of our thinking current, the rate at which one thought follows others, varies. It may be faster in the evening than in the early morning. In depression, it is likely to be slowed down. In hypomania and in psychostimulant intoxication, it will be accelerated.
What is the relationship of the flow of thought to the experience of being aware of oneself? Is it ever possible to be devoid of thoughts and still be acutely conscious? In hypnosis, the flow of thoughts sometimes is reported to stop completely. At the same time, the individual is alert and aware, is not depressed, and knows that thoughts have ceased coming to mind. Often, there is a sense of amazement that awareness of one's awareness is exquisitely preserved, when all the while thoughts have desisted in manifesting themselves (Ludwig 1972).
When the current of thought is slowed, its structure is also likely to be changed. Trance logic refers to mental mechanisms in which logically incongruous ideas can coexist without clashing (Orne 1959). A student of mathematics, for example, came out of his hypnotic experience with a feeling of wonderment. During his hypnotic session he said he had felt, however fleetingly, the concept of infinite distance and endless time. After hypnosis, he talked about the experience as an everlasting revelation that, in spite of his efforts, his rational self could not experientially retrieve.
Emotional Changes
Although the word emotion most directly conveys the idea of a feeling, it is in fact a conglomerate body of processes involving the autonomic nervous system and many psychological associations (Bryant 1989).
Although it is possible in hypnosis to quell emotions as in deep relaxation, it is also possible to enhance certain feeling states. Sometimes, during a hypnotherapeutic situation, a solitary feeling may be presented to the patient for contemplation and amplification. A demoralized individual, for example, may be asked to center solely upon a sensation of optimism. For some participants this can be difficult because they may need to have an actual memory trace or a contextual milieu for this feeling. In this situation, a specific life event can be resurrected, one that was associated with happiness, feelings of self-confidence, and situational mastery. These feelings, once recreated, can be then hypnotically intensified so that they may exert their posthypnotic ego-strengthening influence.
An interesting feature of hypnotically induced feelings is that they tend to persist beyond the hypnotic session. This phenomenon draws associations to Papez's description of how emotions reverberate in the limbic system (Papez 1937). For example, a chronically depressed patient at age 54 could not recall any instance during his life when he experienced feelings of happiness. Then, during one of his sessions, he retrieved the memory of walking as a small boy with his uncle in the countryside, not far from some railroad tracks. A train whistled in the distance and he started imitating its sound and running in a skipping way. He remembered feeling happy then, if only for a few evanescent moments. In hypnosis, he was asked to invite those same feelings into his awareness, to then amplify them through meditative focusing. The ability to experience feelings of joy and freedom became progressively easier, and he gradually started to integrate them into his everyday life, coloring his existence with more joyfulness.
Changes in Imagination
To some degree, the ability to create mental images is present in everyone. It is most pronounced in dreams when the messages flowing from the sense organs are drastically reduced and awareness is shifted to the ever-ongoing inner mental life. In the waking state, the effervescence of mental images surfaces in daydreams. The imagery of daydreams is complex, under partial volitional control, and uniquely expressed in everyone; they may contain visual impressions, feelings, some aesthetic sensations, the interplay of dialogue, and intricate scenarios. Daydreams may be so engrossing that coming back to reality feels shocking.
Clinically, it is important to know the style of imagery used by our patients. In hypnotic induction and in treatment, the stimulation of imagery, in any one of its modalities, provides an important vehicle for progress. It makes little sense, for example, to reduce relaxation by suggesting a sense of heaviness in the body musculature when someone much more naturally responds to suggestions of warmth (i.e., the image of lying down in heated sand), or to more visual scenes (i.e., seeing oneself in a verdant garden or a sunbathed beach) (Kroger 1976).
The ability to create, intensify, and sustain images is enhanced in hypnosis (Hammond 1990). In certain participants, this faculty can be activated to such a degree that the sense of reality recedes and imagery takes precedence. We then have a situation in which the processes of wakefulness coexist with the processes of imagery formation. Further along this continuum, imagery can be so intensely vivid that it is referred to as a hallucination: With eyes open, the participant is able to see an object or a person as if it were there. Conversely, the participant might also not see an object that really is there, a negative hallucination.
Imagery is turned into a therapeutic tool in hypnosis. Images constructed by the patient can, through their real representations or the symbol they convey, point in the direction of creative insight, enhanced self-perception, personal growth, and problem resolution. Through their influence, they have been found to exert important therapeutic effects (Porter 1978, Sheikh 1978).
Hypnotic Effects Upon the Senses
Every second, in the uncharted leap of body to mind, billions of sensory inflow signals become actualized sensations. A hand dipped in the icy water of a wintry lake, for example, will send signals via the lateral spinothalamic tract to nuclei in the thalamus, then on to the postcentral gyrus. Somewhere along the way, feelings of cold will be created. This raw sensation can, however, be modified by other areas of the mind. The sudden startle of a flight of birds in our wintry scene will shift patterns of perception, and the feeling of cold will momentarily be overridden.
Hypnosis mobilizes this ability to move into or away from sensory experience. Sensations can be made to expand or recede. For example, a participant may be convinced to feel pain more distant, less insistent, less sharp and more diffuse, less lancinating and more soothingly warm, or anesthetizingly cold. The process by which this is done can be learned by the patient for therapeutic gain. The stroke victim can be taught to home in on awareness of the vestiges of sensory inputs in an affected limb, in order to make it more functional with time (Appel 1992, Warner 1988). The child accident victim can be guided to veer away from the insistent annoyance of uncomfortable casts to aid in the quality and speed of recovery.
Memory Changes
As dreams dramatically show, the distant and detailed memories of childhood years can be vividly brought back to us as adults. The nervous system stores every experience. New experiences are recorded in its substance, in a sequenced series of bioexperiential events requiring, for their integrity, the proper functioning of short, intermediate, and long-term memory mechanisms.
Many memories, although indelibly present, do not gain entrance to consciousness because they are connected to too much anxiety or psychic pain. Others are cast aside because, in the priority of things, they have little relevance. Conversely, some memories impinge too insistently upon daily life experience and may be disruptive. With effort, one can push for the retrieval of a forgotten detail or, as in suppression, one can consciously coax into oblivion an uncomfortable fact.
The ability of the mind to modulate access to personal memory stores is itself a malleable quality. In the hypnotic state, the individual may be asked to move away from present reality and to rekindle the remembrance of an event (Dinges 1992, Schacter 1996). This phenomenon of enhanced recall is called hypermnesia.
In the phenomenon of posthypnotic amnesia, the subject forgets what has transpired during the hypnotic experience (Williamsen 1965). This effect may occur on its own, or may be encouraged by suggestions (Kinnunen 1996). In either case, the elements of the experience usually return to awareness at some point in the future, typically some days after the event.
Age Regression and Revivification
Whereas memory retrieval and hypermnesia involve a coming to the surface of specific events and effects, age regression implies a more complex phenomenon, namely the reliving of a part of the past in the context of the developmental stage of that time (Orne 1951).
For example, an adult subject (it usually has to be a hypnotically talented one), is asked to travel backward to relive some segment of his adolescence. The hypnotist advises, "You are now about 15 years old. Can you talk about what you are doing and how you feel?" The participant begins an inward search and then talks about an event with varying amounts of detail and effect. Why, of all possible remembrances, did he home in on the memory he chose?
In the hypnotherapy situation, if the event is emotionally charged, the participant may be asked to act as if he is on the side lines, as an observer, in order to reduce the possible affectual impact and its possible disruptive effects. In complete age regression, the episode is relived in all its immediacy and intensity. We are reminded of Penfield's patients who, when cortically stimulated, could actually re-experience segments of their past in their proper sequence (Penfield 1950). With further regression, the expressions, verbal intonations, and the emotional responses of the period re-emerge, turning back developmental time. Regressed to infancy, there may be drooling, monosyllables, and sometimes, amazingly, a Babinski reflex (Raikov 1982). Clinically, age regression and revivification find usefulness in the clarification, release, and reintegration of repressed affect in preparation for conflict resolution and psychological liberation.
"ANESTHESIA AWARENESS" AND ITS RELATION TO HYPNOSIS
The phenomenon of the possible preservation of portions of awareness during chemical anesthesia is not strictly a mainstream feature of hypnosis. However, it presents fascinating theoretical questions and research directions into the dynamics of awareness as they relate to various mental states. The crucial connective thread between hypnosis and anesthesia comes from data suggesting that events occurring during anesthesia may be retrieved by the use of hypnosis (Edwin 1990), and that the process of anesthesia itself may be beneficially influenced by hypnotic intervention (Erickson 1994).
It has been assumed for decades that a patient in the moderate or even deeper levels of chemical anesthesia was in a state of other-worldliness and had relinquished all semblance of consciousness. Some authors (Crile 1947), however, began to study the relationship between anesthesia and awareness and described instances in which the coexistence of the two were not necessarily incompatible.
Recent studies have increasingly focused upon hypnotic recollection of the anesthesia experience (Rossi 1988). Although consciously, many of the patients have little or no memory of their surgical experience, some (especially highly hypnotizable ones) are able to reconnect with these buried memories, in the context of trance.
It has been reasonably established that some patients in such situations are attuned to meaningful communications by the treating personnel (Wilson 1969). This occurrence has prompted hypnotherapists to introduce suggestions to patients awaiting operative procedures; these suggestions are designed to protect the patients against inadvertent negative communications, which may be reacted to, physiologically or psychologically, with nefarious stress reactions. For example, in the event that one of the operating personnel mentions, "there is a lot of blood loss here," the patient may respond with a rise in blood pressure and increased heart rate, promoting cardiac instability. In such a situation, affirmative hypnotic suggestions can act not only as a protective buffer but also as an activator to positive adaptation mechanisms, making successful negotiation of the surgical process more likely (Nathan 1987).
CURRENT CONCEPTS OF HYPNOSIS
Although the manifestations and capabilities of hypnosis have received increasing acknowledgment, the essence of its mechanisms remains difficult to define (Chaves 1994). Today, even with the impressive advances in the understanding of psychological mechanisms, theories of hypnosis are remarkably numerous and divergent (Lynn 1991). The search for a unified theory has been elusive. To be integrated, such a theory would have to explain the multitude of hypnotic phenomena, from age regression to anesthesia and from catalepsy to hallucination; it would have to account for the wide ranges of individual manifestations and show the reasons for the striking subjective experiences that are often induced.
Because theories are approximations, it is probable that several of them are concurrently valid, each seeing a portion of a multidimensional process involving psychological, physiological, and social mechanisms. The following theories are important currents of thought regarding hypnotic phenomena.
Physiological Theories
Those who correlate conditions of consciousness with changes in the central nervous system or those who hold that physiological events may precede all mental events look for physical reasons to explain hypnosis (i.e., variations in the EEG, in evoked potentials, in cerebral blood flow, or in neurotransmitter dynamics) (Spiegel 1992). In the future, as the sophistication in noninvasive central nervous system visualization techniques progresses, the most subtle elements of the physiological accompaniments of the hypnotic condition may yield its yet elusive enigmas. Difficulties with this approach have to do partly with the different manifestations of hypnotic states. For example, in passive or in neutral self-hypnosis, in which participants are physiologically slowed down, we would expect readings in all the previously mentioned tests to be different from those taken during active hypnosis, where the participant, eyes open and alert, may be very task-oriented.
Investigations into the function of the reticular activating system, the diffuse thalamic projections, the activities of the frontal lobes, and the limbic system have been inconclusive. We still do not possess sufficient knowledge about the functioning of these areas of the central nervous system as they relate to the creation of normal consciousness, let alone hypnosis.
There are investigators who share Charcot's concepts that hypnosis is based upon physiological disturbances (Guillain 1955) or Pavlov's ideas of cortical alterations of function and the mechanics of energy in psychic activity (Drabovitch 1934, Kraines 1969). For some, the right hemisphere, with its connectedness to imagery and feeling states, is more involved with hypnotic phenomena (Gabel 1988). Others have been impressed by behavioral or anatomical capabilities such as the eye-roll sign (the capacity of the eyes to roll backward into the head) as reliable indicators of hypnotic susceptibility (Spiegel 1978).
Because body and mind are likely to converge at some yet unknown interface of brain function, it is conceivable that hypnosis, at some level, encompasses some tangible bodily functions. The question remains then: If a particular neurophysiological constellation proves to be a characteristic feature of hypnosis, is it an effect of hypnosis or a cause?
Sleep State Theory
Early magnetists were fooled by the resemblance of the hypnotic state to sleep (Gravitz 1991). They assumed that because their subjects were in a state of slumber, hypnosis was indeed a variant of the sleeping state. Yet, they could not resolve the apparent contradiction that their subjects behaved, in many ways, more as if awake than asleep (Darnton 1970).
In recent years, sleep has been increasingly studied and has become more equated with a state of aliveness than one of suspended animation. It has been divided and subdivided into stages, correlated with a variety of dreaming activities, neurohumoral shifts, neurotransmitter metabolism changes, and chronobiological cycles. Sleep is a dynamic, phasic process with, presumably, several functions, some of which are still unclear. Could hypnosis possibly be one of the many sleep stages? Or is hypnosis a sleep stage with some degree of awareness added to it, as in the phenomenon of lucid dreaming, in which the individual, while remaining asleep, attains the awareness that the dream is, in actuality, part of the process of dreaming itself (Tart 1979)?
Pavlov termed hypnosis "partial sleep." In his view, both sleep and hypnosis resulted from the inhibition of certain cerebral areas. In hypnosis, he postulated, the preservation of "sentinel points" or channels of communication accounted for some limited reactivity to surroundings (Pavlov 1923). Some investigators point out that light sleep can become hypnotic-like by means of establishing rapport through response to suggestion, and that, at times, hypnotized individuals have fallen asleep when left undisturbed or given appropriate suggestions. (Greenleaf 1986).
Because hypnosis has some, albeit limited, common denominators to certain sleep states, it is understandable that the functioning of the neurological pathways involved in the physiology of sleep kindles special inquisitiveness. Among these are certain postulated subcortical sleep-regulating nuclei adjoining the third ventricle, the contributions of the reticular formation, selected pontine nuclei, and the neurotransmitter serotonin. Whether these structures and their associated biochemical components are necessarily directly involved in hypnosis is unknown (Levitt 1963). When global physiological measures are considered, however, hypnosis is very close to wakefulness. Reflexes are not altered in hypnosis, whereas in sleep, they are diminished or absent. Moreover, steep is accompanied by marked modifications in the output of awareness because it is channeled into the environment, whereas in hypnosis, responsiveness to outside stimuli is preserved. In the current analysis, hypnosis appears to be a condition that is neither the usual waking state nor any of the sleep stages.
Hypnosis as a Modified or Special State of Consciousness
The view that hypnosis is a special state of consciousness finds many followers (James 1935, Silverman 1968) who point out that individuals often report experiences outside the realm of their ordinary reality. Many deeply hypnotized participants describe how incredibly relaxed or peaceful their experience was, and how differently they perceived the flow of time, the configuration of their body image, or the experiencing of their awareness (Shor 1962). The usual waking state has a familiar experiential quality. We know it to be there most of our waking hours and, it is argued, we would know of any significant deviation from it.
During hypnosis, this subjective alteration in the personal field of awareness or aliveness is correlated by "state of consciousness" (or state) theorists to depths of hypnosis (Tart 1975, Ludwig 1972). To determine how "deeply" an individual has experienced trance in this system, we would ask for an introspective report, usually with reference to an arbitrary scale (Tart 1979). For example, zero could represent the usual waking state and 10 the deepest trance the participant estimates could be attained.
State theorists posit quantitative (in, for example, the substantivity of consciousness), as well as qualitative changes (certain mental processes may be more or less operational, that is, shift to primary process thinking, alterations in ego mechanisms, or redirection to introspective orientation).
A strong support for the state theory is the occurrence of trance logic that refers to the ability of deeply hypnotized subjects to experience comfortably the coexistence of logically inconsistent perceptions or ideas (Orne 1959). The "ability of the subject to mix freely his perceptions derived from reality from those that stem from imagination and are perceived as hallucinations" cannot be done by imitators (Martin 1996). However, trance logic is also found in dreams, in primary process thinking, and in schizophrenia. How unique is it to hypnosis?
If the waking state is one state of consciousness, albeit the dominant one, and hypnosis is another, we may then ask, how many states are there? Is there a spectrum of states? If so, how does hypnosis fit into it? Is the usual state of consciousness experienced in the same fashion by everyone, or are there significant individual variations?
The school of states of consciousness develops many of its concepts from Eastern philosophies, which have a much longer tradition of interest in these areas (Sheikh 1981). In the Western tradition, states of mind are often equated with neurological and psychiatric conditions having repercussions upon consciousness (i.e., hyperalertness, sedation, stupor, light coma, or deep coma) and part of the problem in defining hypnosis may be semantic: At this time, we may not have developed the terminology to describe the complex and varied conscious mental configuration in the mind's repertory.
Although theorists often put themselves in state and nonstate camps, these divisions may, in the end, be unnecessarily polarizing (Perry 1992). A more integrated view would see hypnotic phenomena as occurring within the context of certain mental sets (state theory) and as capable of being intensified and shaped by many relevant influences, such as social communication, cognitive factors, and interpersonal variables (nonstate theory).
Hypnosis as an Atavistic Phenomenon
This theoretical view holds that hypnosis represents a more primordial style of mentation, a return to an archaic mental functioning, in which suggestion plays an important role (Meares 1972). This primeval mental state is normally superseded, but not replaced, in the waking state by logical, intellectual, and critical faculties. In this model, during the antediluvian periods of their mental evolution, humans functioned much more fully in modes of thought in which nonverbal communication, "hypnotic-like" rapport, and body/mind connectedness were in prominent evidence (Nash 1989).
In the perspective of this theory, several facets of hypnosis may be explained: In many hypnotic inductions, critical faculties are placed at bay by giving monotonous, repetitive suggestions. The prestige of the hypnotherapist is influential, perhaps in the same way as that of important figures long ago in our evolutionary past. Nonverbal communications are well known to occur prominently in hypnosis (Erickson 1959). The participant often reports being able to draw inferences from many subliminal cues and to have increased sensitivity to the meta-meaning and the emotional messages inherent in communications.
In the atavistic hypothesis, depth of hypnosis can be equated to completeness of regression. Spontaneous pseudo-trance or daydreams could represent a mixture of noetic and atavistic processes. Posthypnotic suggestion phenomena, the remarkable action by which instructions given during hypnosis are carried out seemingly automatically at some point in the future, and sometimes in the distant future, are explained by a mechanism of introjection, in which a participant accepts the hypnotist's messages as his own and carries them out as self-fulfilling time-released personal actions.
The atavistic theory is attractive, but it does not adequately account for hypnotic phenomena such as anesthesia and hallucinations.
Psychoanalytically Oriented Theories
Somewhat similar to the atavistic theory, but much more centered on stages of personal development, are psychoanalytically inspired theories of hypnosis that see portions of the participant's psyche as regressing to an infantile ego state, with the hypnotherapist acting as a parental figure (Schilder 1956). The concept of hypnotic rapport becomes imbued with notions of transference, the process by which feelings, attitudes, and wishes, originally linked with an important person in one's earlier life, are channeled onto others (Gill 1959).
Freud had difficulty integrating hypnosis into his psychoanalytic theories. He was strongly influenced by the ideas of both Charcot and Bernheim (Bernheim 1897), but came to see hypnotic phenomena through the perspective of transference (Ellenberger 1970). We may ask whether transference, like suggestibility, is a surface manifestation of hypnosis, or a primary ingredient.
Ferenczi believed that hypnosis recapitulated the Oedipal situation (Ferenczi 1909). He also used expressions such as "paternal hypnosis" and "maternal hypnosis to further describe the nature of the libidinal regression. If the induction was of the authoritarian or commanding type, the subject would associate the hypnotist with a strong father and, if permissive, with the mother. Implied in this view is a gender-oriented element in the hypnotic condition that, barring some claims by occasional subjects who experience erotic feelings in their trance, is not borne out by clinical observations.
In the psychoanalytic view, hypnosis implies a regressed condition in which magical expectations, dependency strivings, and primitive wishes and fears are operational (Schilder 1958, Gruenwald 1982). Because, seen from this Perspective, the hypnotist is placed in an omnipotent position, many psychoanalysts have stayed away from its use. Others, however, pointing to the rich potential of the transference condition implied in hypnosis, have integrated its applications within the psychotherapeutic context (Wolberg 1964).
Hypnosis as a Dissociative Condition
To Haule, the concept of dissociation was central to hypnosis (Haule 1986). Dissociation may be defined as a personality trait, characterized by modification of connections between affect, cognition, and perception of voluntary control over behavior, as well as modifications in the subjective experience of affect, voluntary control, and perception (Sanders 1986). In this process, a body of ideas, emotions, and behaviors is capable of splitting off from the personality to express itself with a certain degree of autonomy. This dissociated material, actively separated from awareness, can be brought to manifest itself through the use of certain techniques, among them hypnosis (Bowers 1991).
Automatic handwriting provides a poignant illustration of this phenomenon: The participant, conscious and alert, can watch his hand write out answers to questions or even produce lengthy narratives, as if detached from the supervision of the self. In this situation, there is an observing ego and a dissociated ego that is perceived by the observing ego as acting independently. In clinical situations, these two egos can be seen when the participant, during induction with the arm levitation method, for example, is amazed to feel his arm rising, seemingly by itself, to eventually touch his face, thus signaling the onset of hypnosis.
Although we do not know the precise nature of the mechanisms of dissociation (Counts 1990), either in the central nervous system or in the psychological architecture, this theory describes some but not all of the characteristics of hypnosis. The relationship of hypnotizability to the capacity for dissociation continues to require further elucidation (Frankel 1990).
Ego State Theory
Ego state theory is closely connected to dissociation theory and also to concepts dealing with the phenomenon of multiple personality, psychogenic amnesia, and fugue states.
Ego state theory postulates the existence of networks of personality traits, experiences, feelings and behaviors, which in various degrees of cohesion are bound by common principles (Watkins 1991). Several ego states may coexist as fairly distinct entities within the same individual, and their boundaries are thought to be loosely defined and malleable, in contrast to the more rigidly constructed demarcations found in multiple personality syndromes. In the hypnotic situation, different ego states may be communicated with, for the purpose of bringing about a more global psychological integration (ego state therapy) (Beahrs 1982).
Behavioral Theories
This viewpoint contrasts with state theories of hypnosis, seeking to strip the hypnotic state of its status as a separate entity or as a distinct condition of consciousness. To bolster this position, some authors point out that all the phenomena said to occur in the hypnotic condition can be produced in normal subjects in their normal waking state (Barber 1995).
If, side by side, we observe a hypnotized subject and a simulator responding to the best of their abilities to the suggestions of a hypnotherapist, we may have cause to wonder who is who. Using this behavioral perspective, it is true that there may be difficulties in telling them apart because responses to instructions can be so convincing in both situations. Is hypnosis a more or less consciously determined simulation? A role play? Could hypnosis be the expression of complex behaviors fashioned from perceptions to social cues?
To cut through the argument of outright mimicry, we could, as amply documented by historical examples (the work of Esdaille in particular [Esdaille 1950]), attempt to perform a major operation on the hypnotized individual without recourse to chemical anesthesia. It is likely that the simulator, on approach of the scalpel, will quickly give up the charade. Simulators may, in addition, have difficulties faking the appearance of a Babinski reflex during age regression, or truly experiencing an auditory or visual hallucination.
Simulation is a conscious maneuver. On a more unconscious level, however, some theorists believe (Sarbin 1972) that hypnosis derives from deep motivations to behave like a hypnotized person should. The definition of what constitutes hypnotic behavior can be overtly or subtly communicated by our culture or by the hypnotherapist who presents cues, verbal and nonverbal, to this effect. This definition would explain the varied manifestations of hypnosis in different cultures and during different historical periods, but it would not elucidate the deeper intrapsychic mechanisms presumably needed for their creation.
The drive to behave in ways suggested by the hypnotherapist is related, in this model, to the completeness of the hypnotic rapport. The strength of the motivation to fulfill the hypnotist's expectations has been proven to be remarkably strong in some individuals (task motivation) (Megas 1975). It is felt that the role-taking behavior of the subject may be so complete, profound, and intense that there is total belief in its consistency and validity. The behavior of the hypnotized individual becomes wholely congruent with self-image and the suggested perception of reality assumes such complete self-syntonicity that phenomena, even phenomena involving the deepest mechanisms of perception and the participation of the autonomic nervous system, are spontaneously expressed.
Hemispheric Laterality Theory
It has been long assumed that the brain is an organ whose symmetry implied an equal sharing, by each hemisphere, of its many functions. For centuries, the contributions made by the brain were not realized; yet the Ebers Papyrus (2500 BC) tells of a man who, as a result of head injuries "lost his ability for speech without paralysis of his tongue." Later, Roman physicians described deficiencies in consciousness, perception, and behavior due to cerebral traumas incurred by gladiators. In 1861, Broca described a patient who had lost the "faculty for articulated speech," with the sparing of verbal and written comprehension, as a result of a left hemispheric lesion. In 1874 Wernicke described a different syndrome, loss of verbal comprehension with preservation of elocution, as a sequela of a lesion in the posterior portion of the first temporal gyrus (Gardner 1975).
Since these early findings, the brain "localizationists" have worked to find discrete territories for each of the many faculties expressed by humans. Although successful for purely motor or sensory modalities, this compartmentalizing approach has had many difficulties with the mapping of associational areas and with such psychological dimensions as emotionality, intelligence, and other higher mental functions. This line of research has provided an appreciation for the intricacies and the plasticity of the brain--as seen, for example, in its adaptation to injury--and for the dynamic interrelatedness of both hemispheres as they complement each other.
Sketching some global differences, the left hemisphere in most individuals has more jurisdiction over expressive speech, syntax, writing, reading, arithmetic, and rhythm; the right hemisphere has greater involvement in processing visual patterns, spatial configurations, holistic analyses, melody, imagery, and the proper interpretation of special meaning and metaphors.
It is in this area that hypnosis and hemispheric function meet (Frumkin 1978). Can resistance to induction be considered a manifestation of logical left hemispheric overbearance? By what neurophysiological mechanisms do techniques such as confusion, paradox, double-bind (the simultaneous communication of conflicting messages), or reframing (changing a person's perspective of events or situations in order to change their meaning), work to circumvent them? How can abilities inherently present in the right or the left hemisphere be best utilized to enhance the effectiveness of therapeutic hypnotic intervention?
HYPNOSIS--QUESTIONS FOR THE FUTURE
The many unresolved issues concerning the nature of hypnosis and the growing sophistication in its exercise make its future promising in numerous areas, from research to clinical practice. At the same time, and this is seen in the increasing volume of papers dealing with hypnosis (Graham 1991), there is widening medical and public acceptance of its therapeutic potential (Fromm 1972). Since its birth as a science, hypnosis has shown a cyclical evolution with fluctuating levels of interest from the scientific community. Today, however, hypnosis appears to be firmly implanted as a medical tool, and its future is likely to witness its progressive maturation in its varied applications to the spectrum of medical practice (Morgan 1992).
Since the early work of Breuer and Freud, hypnosis has found a place in the study of repression, conversion, dissociation, catharsis, and psychogenic amnesia, among other preconscious and unconscious processes. Although relatively abandoned for decades in favor of free association and dream interpretation (Cheek 1995), hypnosis has recently been "rediscovered" for the experimental investigation of conflicts, for the study of ego-homeostasis and enhancement, and for the therapeutic utilization of imagery. Somewhat akin to the population of identified neurotropic molecules that is steadily growing in number, the dynamics of the psychological processes in hypnosis will likely continue to yield ever greater evidence of their variety, complexity, and plasticity. With this knowledge, techniques of hypnotic treatment will become more efficient and more accessible to patients.
There is currently a tendency to integrate different therapeutic modalities in the promise of achieving more efficient individual change. The future of hypnosis will likely witness studies of its usefulness as a facilitator to other therapies, much as hypnobehavioral approaches have already been applied to systematic desensitization, aversion, flooding, assertiveness training, short-term dynamic psychotherapy, and imagery techniques.
As a quintessential facilitator to mind/body communications, hypnosis will continue to become integrated into holistic patient care. Facilitating this integration is research that points to the interconnectedness of all phenomena, mental and physical, in the organism. Psychoneuroimmunology, for example--the science of the interactive relationship between neurophysiological, immune system, and mental functions--continues to demonstrate the potent contribution of the psyche to the function of all biological processes (Vishwanath 1996).
Some medical specialties geared to the management of human factors inherent to novel technologies will invite specialized mind/body disciplines, including hypnosis, to enhance their therapeutic capacity. In space medicine, for example, the possibility of applying hypnotic phenomena to the problems encountered by space mission crews is being explored. Nausea associated with prolonged weightlessness is a particularly disabling problem, poorly controlled by medications. Self-hypnosis has clear potential to modify, and in many cases to abolish space-engendered symptoms without depressing consciousness or creating side effects. It can also assist in the adjustment to new circadian rhythms and in the attainment of deep relaxation designed to make the best of erratic rest periods. It is conceivable, in future missions requiring long travel time, that crew selection will privilege the ability to induce prolonged trances.
In view of these considerations, it is evident that hypnosis presents fascinating opportunities for medical and psychotherapeutic research. Aside from these very tangible promises, the mental mechanisms responsible for the vast array of hypnotic phenomena, once understood, can open rich insights, not only into the most intimate connections of body to mind, but into the nature of consciousness itself.
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