Magnitude estimates of cold pressor pain: effects of suggestions, cognitive strategy, and tolerance

Pain magnitude when subjects immersed an arm in ice water was assessed by means of a magnitude estimation procedure during baseline and posttest sessions. Before the posttest session, subjects either received or did not receive an analgesic suggestion. Best-fit functions were linear, though power fits were also good. Analgesic suggestions had no effect on the rate of change in pain intensity. When subjects were classified as copers or catastrophizers on the basis of written testimony, pain intensity increased more rapidly for catastrophizers than for copers during the posttest session but not during the baseline session. Subjects who kept their arm immersed for more than 240 s were classified as high in tolerance. High-tolerance subjects experienced a slower rate of growth in pain intensity than low-tolerance subjects. Theoretical implications of the results are discussed.     

The effects of contextual information and gender on the prediction of hypnotic susceptibility

Council, Kirsch, and Hafner (1986) obtained empirical support for the hypothesis that significant correlations between questionnaire measures of absorption and hypnotic susceptibility are an artifact of subjects' beliefs about their own hypnotizability. We tested this hypothesis in a two-session experiment. During Session 1, subjects completed questionnaire measures of absorption, mystical experience, daydreaming frequency, and paranormal beliefs. During Session 2, subjects were tested for hypnotic susceptibility. Subjects were also exposed to one of three information manipulations: They were told about hypnotic testing either before or after filling out the questionnaires or were not told about hypnotic testing. The information manipulation moderated the prediction of susceptibility by the questionnaire measures for women, but not for men. For women, scores on the absorption questionnaire predicted susceptibility only when subjects were informed about hypnotic testing. In the told-after condition, this effect generalized to all of the remaining questionnaire measures. For men, none of the questionnaires was a reliable predictor of susceptibility.     

The effects of suggestion structure and hypnotic vs task-motivation instructions on response to hallucination suggestions

Hypnotic and task-motivated subjects were given both auditory and visual hallucination suggestions that were either Brief, Long, or provided an imaginary Context. The Long and Context suggestions were equated for length. Task-motivated subjects scored higher than hypnotic subjects on both auditory and visual hallucination suggestions. Suggestion-type (Brief, Long, Context) affected response to the auditory but not the visual suggestion. Hypnotic and task-motivated hallucinators were equally likely to describe their images as being transparent. Theoretical implications are discussed.     

The social nature of hypnosis: An ethogenic analysis of hypnotic pain reduction

This article addresses the central paradox of hypnotic pain reduction: the discrepancy between self-reports and physiological measures of pain, using a constructionist perspective. The analysis is embedded in the ethogenic assumptions about the nature of the social and in realist rather than positivist notions of causality. It reformulates the induction procedure as an entrance ritual, considers the hypnosis experiment proper as a social episode, reveals the causal powers that subjects bring to hypnosis experiments and specifies how the act of hypnotic pain reduction is achieved. The analysis uses, in part, the Olympic athlete and the Olympic competition as analogic models to show that the hypnosis experiment is merely a public occasion for talented hypnotic subjects to display their peculiar powers without risking their standing as rational beings. The paradox is seen to be an artifact of positivist assumptions concerning both the nature of hypnosis and of traditional experimental methods. Two distinct lines of investigation, based on the competence/performance distinction, are recommended as guides for future research.     

The role of compliance in hypnotic and nonhypnotic analgesia

We modified the standard procedure for administering finger pressure pain in order to assess the extent to which subjects biased their reports of pain reduction when exposed to compliance-inducing instructions. Experiment 1 used only highly hypnotizable subjects and found that compliance-induced reductions in reported pain were about half as large as the reported reductions produced by hypnotic analgesia suggestions. Experiment 2 used low as well as high hypnotizables and administered hypnotic or nonhypnotic analgesia instructions and compliance instructions to the same subjects on separate pain trials. Reported pain reductions produced by hypnotic and nonhypnotic analgesia suggestions and those produced by compliance instructions were substantially and significantly correlated. Furthermore, hypnotizability correlated with compliance-induced reported pain reductions as highly as it correlated with the reported reductions produced by hypnotic analgesia suggestions. Among high hypnotizables (but not low hypnotizables) compliant responding was predicted by social desirability. The findings of both studies indicate that compliance strongly influences the reports of hypnotic and nonhypnotic analgesia proffered by high hypnotizables. The role of compliance in the pain reductions reported by low hypnotizables is less clear-cut.     

The effect of specific hypnotic suggestions on blood pressure in normotensive subjects

Twenty normotensive subjects participated on a voluntary basis in an experiment designed to study the effects of specific suggestions on blood pressure (BP). After an induction procedure, the experimental group received suggestions presumed to be relatively nonactivating, although capable of lowering or raising BP. A control group was used to record the BP changes over time. All subjects met for one session. Eight subjects from the experimental group met for a second session. Both adaptation and induction resulted in significant BP decreases. A specific suggestion to increase BP gave a significant result when compared to the induction point. There was no significant change from induction to the BP decrease suggestion. Both systolic and diastolic BP behaved in the same way. A second experimental session resulted in no significant change compared with the first session. Also, no significant difference was found in suggestibility scores from the first to the second session. The results are in line with previously published studies.     

Imagery vividness, hypnotic susceptibility, and the perception of fragmented stimuli

Two experiments were conducted to determine the role of hypnotic susceptibility level (high or low) and imaging ability (vivid or poor) in the performance of gestalt closure tasks. In Experiment 1, subjects were required to identify fragmented stimuli in the Closure Speed Test and in the Street Test. In Experiment 2, subjects reported on fragmented stimuli that were projected to the right eye and subsequently produced an afterimage. Individuals were asked to identify the composite if possible and to report on the duration of the afterimage. In both experiments, hypnotic susceptibility level and imaging ability affected reports of gestalt closure. The greatest number of correct closures was reported by those who were both high in hypnotic susceptibility and vivid in imaging ability. In addition, in the second experiment, this group also reported the longest enduring afterimage. These results are discussed in terms of the processes required to perform in a gestalt closure task.