This article originally appeared in The Skeptic, Volume 4, Issue 1, from 1990.
Take statements like these: ‘I don’t remember where I heard that’; ‘I’ve forgotten the word’; ‘I don’t know why I did that’; ‘It doesn’t hurt’; ‘I’ve gone deaf’; ‘I can’t see it’; ‘It’s red’. There are two ways of finding out whether these statements are true. One is to simply ask the speaker, and believe whatever he says. The other is to sit down and figure out independent ways of getting at the truth.
Hypnosis is a case in point, and for my present purpose I intend to deliberately restrict my main references to one of the latest and largest offerings on the subject – Hypnosis: the Cognitive-Behavioural Perspective, edited by Nicholas P. Spanos and John F. Chaves (Prometheus Books 1989). This is because the book is available to the general public, and saves me from appending a list of references to professional journals that you won’t have ready access to, and won’t consult anyway. The book contains 19 papers in all, and the text is backed up by about 1,500 references that you can chase up if you want to.
What is hypnosis? Spanos and Chaves point out that, for most laypeople and many research workers and health care providers, it involves a trance, or at least an altered state of consciousness. It is brought on by some repetitive verbal rituals, known as an induction procedure. The person hypnotised becomes a passive automaton, and comes under the control of the hypnotist.
The vogue began with the German physician Anton Mesmer in the late 18th century. It became entwined with a range of other occult beliefs, and took on a new lease of life. And now here we are towards the end of the 20th century, with the American Psychological Association sheltering a fully-fledged Division of Psychological Hypnosis (are there other kinds?).
![Book cover of 'Hypnosis: the cognitive-behavioral perspective', highlighting the H and S in 'Hypnosis', above a single eye and a spread of four fingers at the lower end of the image.](https://www.skeptic.org.uk/wp-content/uploads/2024/08/HypnosisCover.jpg)
It is about 40 years now since T. R. Sarbin (one of this book’s contributors) threw out the long-held belief in an ‘altered state of consciousness.’ And in the 1960s, T.X. Barber finally unsheathed the simple weapon that has been the death of so many groundless belief systems – the control group.
Usually one group was given a hypnotic induction procedure. A second group was asked to just imagine whatever was suggested to them. And a third group was simply urged to do their best to respond to suggestions.
‘Hypnotised’ subjects responded to suggestions for age regression, hallucination, amnesia, pain reduction, and so forth – but so did the controls. And those who were simply told, “Do your best” did just as well as those who were ‘hypnotised.’ (I’m afraid the word ‘hypnotised’ often has to go about with quotes acting as bodyguards.)
Other workers soon found that non-hypnotic subjects also did as well in producing “so called immoral, self-destructive, or criminal behaviour.” It turned out that all subjects knew perfectly well that they must be safe from harm, since they were aware they were taking part in experiments in an academic setting.
The subjects who showed up best in tests of hypnotic susceptibility were those who had been asked to pretend to be hypnotised. And hypnotic performance could be noticeably improved by some training. In other words, what had been thought of as a genetically endowed susceptibility was in fact a skill that could be learned.
The fact is that hypnotic subjects know how hypnotic subjects are supposed to behave, and their general goal is “to behave like a hypnotised person as this is continuously defined by the operator and understood by the subject.” ( R.W. White) For many subjects, merely defining the situation as hypnosis results in them classifying everyday behaviours like arm raising as ‘involuntary.’
And T.X. Barber and D.S. Calverley made the amusing discovery that when a group of subjects were told that hypnosis was a test of gullibility, “hypnotic responding was virtually nullified.”
When a subject is told that he will perform a certain action on cue, after ‘waking up’, is that action really beyond his control? Thirteen subjects were told to scratch their ear when they heard the word ‘psychology’, and they all did so. The hypnotist gave the impression that the experiment was over, and had an informal conversation with a colleague, in which the cue word was used. 9 of the subjects failed to respond. When the hypnotist then intimated that the experiment was still in progress, 7 of those 9 began responding again. Another experimenter found that all post-hypnotic responding stopped when he left the room, apparently to attend an emergency.
In a similar experiment, Spanos and his associates found that subjects all dutifully coughed when they heard the word ‘psychology’ in the experimental situation. But Spanos had arranged for a confederate to pose as a lost student asking for the psychology department. None of the subjects responded to the cue word.
I.F. Hoyt and J. F. Kihlstrom have concluded that “post-hypnotic information processing is no different than non-hypnotic information processing.” Subjects are sometimes given a post-hypnotic suggestion that they will not remember certain key words. Do they really forget these words? According to their verbal reports, they do. But according to their galvanic skin resistance, they don’t. In another example, subjects are given a list of words to learn. They are then ‘hypnotised’, and given another list to learn. This second list has been constructed so as to interfere with the recall of the first list. Some subjects are then given a post-hypnotic amnesia suggestion to forget the second list. Other subjects are given no suggestion. When recall is tested later, subjects in both groups recall the first list at the same level. William C. Coe asks simply: “Is their amnesia credible?”
Spanos and others found that between 40 and 63 per cent of their ‘amnesic’ subjects later admitted that they had suppressed their reports. Coe wonders: “Perhaps we should wonder how many did not confess?” And he comments: “The ‘skill’ they employ is not reporting.” It is probably no surprise to learn that simulators are just as successful in employing this ‘skill.’ Furthermore, most amnesiacs will confess to remembering more and more of the ‘forgotten’ material under adequate pressure, “to the extent that they have nothing left to remember when amnesia is lifted.”
Hypnotic deafness? If you get someone to read or speak into a microphone, and feed back the sound of his voice into headphones after a momentary time lag, his speech will become seriously disrupted, with slurring, hesitations, and stammering. Hypnotic subjects claiming to be deaf show the same disruptions. ‘High-susceptible’ subjects and ‘low-susceptible’ subjects have been told that they are deaf in one ear. Then pairs of words have been presented simultaneously, one member of the pair to each ear. Subjects should only be able to hear words presented to their ‘good’ ear. In fact both groups show the same number of intrusions from the ‘deaf’ ear.
Colour blindness? When hypnotically colour-blind subjects are shown the Isihara ‘malingering’ card, they report that they can’t see the number that in fact can be seen by all genuinely red-green blind individuals.
Post-hypnotic negative hallucinations? Hypnotically blind subjects continue to process the visual information they claim not to see.
There are a number of standard ways of reducing the effects of pain (eg self-distraction, placebos, relaxation, cognitive re-interpretation, positive imagery). Does hypnosis do a better job? Perhaps the best-known (and most often quoted) person to use mesmerism for surgical pain was the 19th-century physician John Esdaile. He reported thousands of minor surgical procedures as well as several hundred major surgical procedures. Medical workers in Austria, in France, and in the United States all tried to replicate his successes. They all failed. Like the acupuncture miracle-workers of China, Esdaile plied his trade in a distant clime (in his case, India) – “far from the din of skeptical colleagues” in the polite phrase of John F. Chaves.
When the time came to investigate Esdaile’s achievements, the Bengal government appointed a commission. Esdaile selected only ten patients for observation. Three were discarded because they appeared to be unresponsive to his techniques. One case was “inconclusive”.Three showed “convulsive movements of the upper limbs, writhing of the body, distortion of the features, giving the face a hideous expression of suppressed agony…” The remaining three showed no outward sign of pain, though two of them showed erratic pulse rates. This was hardly the wonder anesthetic that everyone had been led to expect.
Esdaile’s tiny (and selective) sample did not take into account the wide variation in different people’s ability to tolerate pain. More recent attempts to use hypnotic analgesia have suffered the same flaws that have ruined the claims for acupuncture analgesia: the treatment has almost always been accompanied by chemical anesthetics, sedation, or local anesthesia. In fact suggestions for reducing the perception of pain can be effective whether accompanied by hypnotic induction or not. And sadly, as Chaves points out, “a recent review of significant developments in medical hypnosis over the past 25 years fails to cite a single report of hypno-analgesia…”
Joyce L. D’Eon reports that in childbirth, “hypnotic procedures have failed to meet the grandiose claims that have sometimes been made for them.” Without the counter-check of a control group, it is all too easy to attribute an easy birth to the use of hypnosis, because “anywhere from 9 to 24 per cent of women experience relatively painless childbirth without any intervention.”
Richard F. Q. Johnson asked 42 prominent researchers if they had ever tried to produce blisters by hypnotic suggestion. Seven said they had obtained positive results. But none had published their results, and they were very skeptical of their findings. They suspected that highly motivated subjects might secretly injure themselves to produce the results the hypnotist wanted.
Nevertheless, further research is called for, especially comparing normal subjects with those who have sensitive skin. After all, anxiety is associated with the production and intensity of other skin ailments, such as hives. Nearly all cases of religious stigmata can be explained in terms of deliberate self-injury. The bleedings are brought to the attention of the investigator only after they have begun, and it is almost impossible to keep a 24-hour watch on the individuals.
Warts? If they are left untreated, they will generally go away of their own accord after two or three years. In a controlled study, 17 patients with warts on both sides of the body were given hypnotic induction, then told that the warts would disappear from one side of the body. Some warts did in fact go away – from both sides of the body. But any treatment that the patient believes in is likely to produce results just as dramatic as those claimed for hypnosis. Johnson summarises: “the skin may at times be strongly influenced by thinking and suggestion. Nevertheless, the precise relationship between verbal suggestion and changes in the skin has yet to be determined.”
Henderikus J. Stam reports: “The use of hypnosis for the treatment of cancer pain, like other psychological techniques for the treatment of this problem, has remained largely untested. The bulk of this literature is in the form of case reports.” His conclusions offer little hope: “Where does this leave the literature on the treatment of cancer pain? More or less where it began, unfortunately. The lack of systematic studies and the continued exaggerated claims made for this technique have left it in scientific and therapeutic limbo.”
Where does the law stand in all this? In the case of K. Bianchi, the so-called Hillside Strangler, the Los Angeles courts gave a curious solidity to the spirit form known as hypnosis. The law ruled that testimony from hypnotised witnesses was not admissible in court. As H. P. de Groot and M.I. Gwynn conclude in their discussion of the case, “it makes little sense to ask whether or not Bianchi was ‘really hypnotised,’ because the construct ‘hypnosis’ has little utility as a scientific account of hypnotic responding.”
In Canadian law, hypnotic suggestion, along with such influences as drugs and alcohol, is allowed as a basis for the defence of ‘automatism’. And the American Law Institute’s Model Penal Code claims that anyone following hypnotic suggestion is not acting voluntarily, so he can’t be considered criminally liable. But various American states offer differing viewpoints.
In England, a judge in Maidstone has ruled that the testimony of four witnesses was not admissible in court, because they had been previously ‘hypnotised’. By contrast, the cognitive-behavioural point of view takes the position that the actions of a ‘hypnotised’ subject are voluntary. T.X. Barber has made the point that explaining a hypnotic subject’s behaviour in terms of a trance or altered state of consciousness is like explaining a shaman’s behaviour in terms of spirit possession. As for hypnotising witnesses to get at the facts, ‘there is no conclusive evidence, either anecdotal or experimental, to indicate that hypnosis can act as a “truth serum.”‘
There is not even any known method for detecting whether anyone is simulating ‘hypnosis’ or not. The likeliest result of allowing the police to use hypnotists would be “the confident reporting of inaccurate information” (P. W. Sheehan and J . Tilden). All in all, “the kinds of experiences and behaviours that are elicited by hypnotic procedures can also be produced by placebos and other expectancy-modification procedures.”
As long ago as 1962, T. R. Sarbin proposed that the term ‘hypnosis’ should be stricken from the professional vocabulary of psychology. That day has still not come, although the cognitive skills involved are being more often referred to nowadays by such terms as ‘goal-directed fantasy’ or ‘think-with suggestions.’
Hypnosis was born at a time when theological explanations were just beginning to give way to the rationality rules of science. So in the late 20th century, who is it who’s still hanging on to this concept of human conduct as a function of strange internal forces, and a vocabulary more suited to occult mysteries? The answer turns out to be – the clinicians. William C. Coe’s study of hypnosis journals is revealing. “It seems that the vast majority of clinicians prefer using special state concepts in vague ways, perhaps naively, or perhaps to mystify purposely. It seems equally clear that the vast majority of experimental investigators avoid using special state concepts.”
From a scientific viewpoint, “hypnotic induction rituals are viewed as historical curiosities that reflect outmoded 19th-century attempts to conceptualise the behaviours associated with this topic as linked in some way to sleep.”
“In short,” say Spanos and Chaves, “clinical hypnosis as a research area appears to be at roughly the same point as experimental hypnosis research before Barber began his systematic controlled experimentation in the late 1950s.”