Science and Hypnosis

SCIENCE AND HYPNOSIS by Gabrielle Harbowy

Some facets of the unknown are difficult to study in an objective fashion, but hypnosis is not one of them. 'Trance states' are prevalent in religious literature from Ancient Egypt to the modern day. Since the work of Dr. Anton Mesmer in the 1700's, science has been exploring the phenomenon of hypnosis, with unexpectedly concrete results.

Early twentieth century research in hypnosis examined the differences between the waking and the hypnotic states. The 1950's had broken down hypnosis down into its component characteristics. Scientists still were not certain what physiological or neurological occurrence *caused* the hypnotic state, but it was theorized that "hypnosis is brought about by electrical blockage between the brain stem reticular formation and specific-sensory, parasensory, and coordinate neuronal channels" (Roberts, 1960).

One-thing researchers agreed upon was that hypnosis was different than the "waking state". What remained unknown was what those differences were. Since subjects often had incomplete or flawed memory of events that had transpired during hypnosis, Gill and Brenman in 1959 interviewed subjects about the hypnosis experience while the subjects were in the hypnotic state. The subjects reported extreme difficulty in performing spontaneous, non-directed action, and difficulty in refraining from performing actions directed by the hypnotist.

Gill and Brenman's research led to the definition of seven characteristics of hypnosis:

Subsidence of the planning function (lack of desire to will action). A subject feels disconnected from her body and may wonder if her legs are crossed, but will lack the motivation to shift them and find out.
Redistribution of attention. A subject will be able, at the hypnotist's suggestion, to exhibit selective attention (listening only to the experimenter's voice) and selective inattention (not even hearing other sounds or voices in the room). Some selective attention is exhibited in everyday life, but the degree to which it is displayed in hypnosis is measurably beyond the normal range.
Availability of visual memories from the past
Decrease in reality testing and tolerance for persistent reality distortion. We all participate in nervous behavior -- fidgeting, adjusting clothing, etc. This 'stimulus-hunger' is in part this need for a contact that maintains location and boundaries of the body in its relation to the external world, and is what is referred to as 'reality testing'. It "is decreased in hypnotized subjects, partly as the result of actions of the hypnotist, with his emphasis on relaxation and detachment" (Hilgard, 1962). As such, we are also more inclined to accept reality distortions -- ideas that go against our set of beliefs about how the world works.
Increased suggestibility. This accompanies the lack of volition. We are less likely to initiate our own actions, so we become more susceptible to the suggestions of others to guide our behavior.
Role behavior. We are more likely to follow suggestions to act out of character, or to behave that way for an extended period of time.
Amnesia for events occurring in the hypnotic state.

These characteristics formed the basis for hypnosis research. Skeptics thought that subjects pretending to be hypnotized could easily fake any of these behaviors. As a result, much of the research into hypnosis in the 1960's was directed at producing a real hypnotic state, and separating it from falsified hypnotic behavior.

Many of these experiments involved pain or extreme discomfort. A person cannot suppress a reaction to cold: our bodies will shiver. Researchers discovered that hypnotized subjects could withstand much lower temperatures without shivering than non-hypnotized subjects could.

In other experiments, galvanic skin response (as is measured by polygraph tests) was used as an indicator of pain sensitivity (Sutcliffe, 1961). Hypnotized subjects were given a strong electric shock. Those who were told not to feel the shock registered all the physiological but none of the behavioral responses to the shock: heart rate and perspiration increased, but the subject did not flinch, jump, or exhibit facial expressions such as wincing. That is, the body felt "something", but the brain did not register it as pain. Similarly, subjects who were told to feel a shock when one did not occur reported pain, winced, and flinched, but did not exhibit increased heart rate or perspiration. As Sutcliffe summarized, "subjective experience is at variance with bodily reaction."

Before modern strict ethical guidelines were developed by the American Psychological Association, these pain-administration experiments were commonplace. A typical way to determine whether a patient was under hypnosis was to jab the subject in the thigh forcefully with a needle. F.L. Marcuse discusses this test in his book "Hypnosis - Fact and Fiction":

"It may be mentioned in passing that when this particular test is given, those few individuals who have deliberately played along to see what happens in the hypnosis session will rather hurriedly decide that they have played along long enough.

"Attempts in the waking state to pretend or simulate lack of sensitivity to pain with regard to flinching, heart rate, and other physiological measurements have not been able to reach that degree of control which is possible hypnotically."

Susceptibility testing

The culmination of these experiments in hypnosis were the susceptibility tests: measures which would allow easily hypnotizable subjects to be screened and selected for further research. The two major susceptibility tests are the Stanford Hypnotic Susceptibility Scale, written in 1959 by Andre Weitzenhoffer and Ernest Hilgard, and the Harvard Group Scale of Hypnotic Susceptibility, written in 1962 by Ronald Shor and Emily Orne.

The Stanford Hypnotic Susceptibility Scale is generally divided into two test-taking sessions. The first session, called Form A, is designed as a group test, and has twelve components on which subjects are scored.

For example, motor responses are carried out automatically as a result of direct suggestion, with loss of volitional control over movement. Items representing this division include: eye closure on command; inability to separate one's hands after being told that they are glued together; and inability to open one's eyes when directed to, after being instructed that they must remain shut.

Form B is a more advanced measure, testing subjects individually and calling for a more interactive hypnotic session. The subject is asked to imagine a sweet, and then a sour taste. To "pass" the test, the subject must indicate tasting both flavors, and make the appropriate involuntary facial expressions (grimacing, etc). The subject is told to inhale an odorless liquid (which is actually strong ammonia). To "pass", the subject must not react to the odor. Subjects who have normal olfactory capabilities and are seeking to deceive the experimenter find this particular subtest impossible to simulate. This test also has twelve items.

Susceptibility, After-Effects, and Credibility

Research has found that subjects most susceptible to hypnosis are women who have experienced some kind of physical, sexual, or emotional abuse. The theory is that these subjects have already taught themselves how to dissociate from reality, "self-hypnotizing" to avoid traumatic situations. Since this type of subject is susceptible, and since, as we have already discussed, people in the hypnotic state are more likely to experience visual memories of past events, it should not be surprising that there are often after-effects experienced by subjects following a hypnosis session. Most experiments on hypnosis have qualified therapists on call to assist the subjects if such a need should arise.

Subjects in the hypnotic state are also more prone to distortions of reality, and to suggestion. Therefore, memories recalled during hypnosis cannot be taken at face value. Often, the subject will unknowingly recall events that are part reality and part fantasy, and will then remember them upon waking as though they had happened in the manner recalled. Witnesses to a crime will accept suggestion about the appearance and behavior of the suspect, and will subsequently "remember" characteristics after hypnosis which eluded them before. Hypnotically-induced testimony is not allowed in court in the United States, unless the testimony can be corroborated by another source. Therapists who hypnotize to access a patient's repressed memories must also keep in mind that a patient under hypnosis is susceptible to suggestion, is lacking in motivation and volition, and therefore may be more likely to follow directions, accept statements, and say what the therapist wants to hear.

Continuing research

Modern research is focusing on anesthetic and therapeutic uses for hypnosis. Since pain is not experienced (or at least not remembered) by subjects, hypnosis is finding experimental uses for patients in all disciplines of medicine. From getting a tooth filled, to undergoing chemotherapy, to giving birth, the treatment of pain is gradually shying away from prescription medications and heading in the direction of hypnosis. Only continued scientific research into the very real phenomenon of hypnosis will make this a reality.

(research references available upon request)