Measuring Hypnosis: Relating the Subjective Experience to Systematic Physiological Changes

Clinical hypnosis is a mind-body technique that operates at the intersection of subjective perceptions and objective physiological changes. A fundamental problem with hypnosis research is that the subjective mental state of patients during hypnosis cannot be measured directly. Experimental paradigms that neglect to measure changes in mental state at best yield a correlation between the treatment procedure and outcomes but cannot demonstrate a causal link. Current practices rely on the subjective reports of the subject to distinguish whether a negative experimental outcome arises because the patient never achieved the hypnotic state or because hypnosis was an ineffective treatment. The purpose of this research is to bridge this gap between the subjective perception of the hypnotic state and objective measurement of concomitant physiological changes. In addition, we seek a technique that can estimate depth of hypnosis during the course of a hypnosis session, on a time scale of less than a minute.