Erickson often pointed out the naturalistic basis of hypnotic pain control. In everyday life, pain can be temporarily abolished simply by the intervention of more compelling concerns. The young mother suffering a severe burn pain will instantly become oblivious to it when her baby falls out of the crib and screams in pain. Football players can finish a ballgame with broken limbs while barely noticing the pain. Watching a suspenseful movie can make us temporarily forget that we have the flu, a sprained back, or an ulcer. Whatever the particular circumstances, consciousness is diverted from registering pain.
Research indicates that while one's apperception of pain may be altered by hypnosis, its physical reality in the body is not. This is no different from neurosis where one feels wonderful but has migraines and high blood pressure and considers them aberrations from this wonderful mental state.
A number of experiments have shown that hypnosis does not block the actual sensory messages of pain on their way into the brain along the peripheral nervous system. This finding suggests that hypnotic pain control takes place at the cortical or cognitive level of the central nervous system – that is, at the third level of consciousness. Other research in the field indicates that although felt pain may be reduced, involuntary physiologic indicators of it continue to register: blood pressure, pulse rate, and temperature are all up. This suggests that oblivion to pain is only "in the head" (literally, in the cortical area of the brain) while the body continues to be affected. More interestingly, it turns out that this cortical oblivion is even incomplete. That is, conscious awareness of pain is not totally eradicated in hypnosis, contrary to what was traditionally assumed. The discovery of this came as quite a surprise to researcher Ernest Hilgard while he was conducting a classroom demonstration, in response to a serendipitous question on hypnotic deafness. He recounts the incident as follows:
The subject of the demonstration was a blind student, experienced in hypnosis, who had volunteered to serve; his blindness was not related to the demonstration, except that any visual cues were eliminated. After induction of hypnosis, he was given the suggestion that, at the count of three, he would become completely deaf to all sounds. His hearing would be restored to normal when the instructor's hand was placed on his right shoulder. To be both blind and deaf would have been a frightening experience for the subject, had he not known that his deafness was quite temporary.
Loud sounds were then made close to the subject's head by banging together some large wooden blocks. There was no sign of reaction whatsoever; none was expected, because the subject had, in a previous demonstration, shown lack of responsiveness to the shots of a starter's pistol. He was completely indifferent to any questions asked of him while hypnotically deaf.
One student in the class questioned whether "some part" of the subject might be aware of what was going on. After all, there was nothing wrong with his ears. The instructor agreed to test this by a method rebated to interrogation practices used by clinical hypnotists. He addressed the hypnotically deaf subject in a quiet voice.
"As you know, there are parts of our nervous system that carry on activities that occur out of awareness, of which control of the circulation of the blood, or the digestive processes, are the most familiar. However, there may be intellectual processes also of which we are unaware, such as those that find expression in night dreams. Although you are hypnotically deaf, perhaps there is some part of you that is hearing my voice and processing the information. If there is, I should like the index finger of your right hand to rise as a sign that this is the case."
To the surprise of the instructor, as well as the class, the finger rose! The subject immediately said, "Please restore my hearing so you can tell me what you did. I felt my finger rise in a way that was not a spontaneous twitch, so you must have done something to make it rise, and I want to know what you did."
Hilgard then began experiments to see if the "hidden observer" phenomenon also occurred in hypnotic pain control. He used "automatic writing" (also "automatic talking") as a tool to "split" the subject's awareness. The subject was told that one arm would be put in ice water while the other would be put "out of awareness." She was then asked to report verbally on how much pain she was feeling in the icy hand, while simultaneously writing a response with the hand that was "out of awareness." It turned out that as she verbally reported no pain in the icy hand, the out-of-awareness hand reported increasing degrees of pain. Another subject, who had his hypnotically-dissociated arm pricked several times with a hypodermic needle, reportedly wrote "Ouch, damn it, you're hurting me." Meanwhile, this subject himself remained oblivious to what was happening, asking when the experiment would begin a few minutes after it had already ended. In other words, the "hidden observer" in each subject reported feeling normal pain while the hypnotized part felt little or not pain. According to Hilgard, such experiments indicate that:
A hypnotized subject who is out of contact with a source of stimulation...may nevertheless register information regarding what is occurring. Further, he may be understanding it so that, under appropriate circumstances, what was unknown to the hypnotized part of him can be uncovered and talked about...It should be noted that the "hidden observer" is a metaphor for something occurring at an intellectual level but not available to the consciousness of the hypnotized person. It does not mean that there is some sort of secondary personality with a life of its own – a kind of homunculus lurking in the shadows of the conscious person. [Italics added]
Following are statements by some of Hilgard's subjects describing their experience of the hidden observer experiments:
It's as though two things were happening simultaneously. I have two separate memories as if two things could have happened to two different people.
Both parts (of me) were concentrating on what you said – not to feel pain. The water bothered the hidden part a little because it felt a little but the hypnotized part was not thinking of my arm at all.
The hidden part knew that my hand was in the water and it hurt just as much as it did the other day (in the waking control session). The hypnotized part would vaguely be aware of feeling pain – that's why I would have to concentrate really hard.
The hidden part knows the pain is there but I'm not sure it feels it. The hypnotized part doesn't feel it but I ' m not sure that the hypnotized part may have known it was there but didn't say it. The hypnotized part really makes an effort. [Original Italics]
Here we see the split clearly described in the subjects' own words. We see the knowing about pain dissociated from the feeling of it. Hilgard points out that even though there was a high level of sensory pain in these hypnotic subjects, there was no distress or suffering accompanying it. When the hypnotic state was lifted, the subjects could remember feeling pain but they did not feel the suffering. In other words, they remembered the feeling but they did not feel it.
Let's take an example of how the countless ways this split occurs outside of experimental situations. A scientist who is a rigid procedurist, never wavering from correct methods, believes in the Moonies and is a devotee (a case I know of). Here the intellect is split in a seamless unity where one part of the intellect sees reality in her science, and the other part is attending to the Pain below by developing belief systems. The Pain seeps into a part of the intellect and forces it to deal with it while keeping the person unconscious of her motivation. Another part has all of its critical faculties intact. It is easy to split the intellect. That is why one can be a crazy paranoid with weird ideas and still work and talk intelligently and rationally. So long as one doesn't touch the Pain, one can deal with the person.
How to explain hypnotic pain control? How to explain the overt and covert levels of reporting in the hidden observer phenomenon? Hilgard proposes a concept of "divided cognitive control systems" which we can shift in and out of via hypnosis. According to Yapko, dissociation from pain "involves the capacity to divide one's attentional and behavioral abilities" and "causes the subjective experience of feeling separated from all or part of one's body, and thus the pain."
In the normal waking state, we have an open communication channel between cognition and response mechanisms so that the sensation of pain is communicated voluntarily through face and body expressions, and involuntarily through vital sign indicators.
Hilgard, Hypnosis in the Relief of Pain, pp. 166-167.
Hilgard, Hypnosis in the Relief of Pain, pp. 168-69.
Ibid., p. 173.
Yapko, Trancework, p. 279.