Placebo versus "Standard" Hypnosis Rationale: Attitudes, Expectancies, Hypnotic Responses, and Experiences

In this study participants were provided with either the standard rationale that accompanies the Harvard Group Scale of Hypnotic Susceptibility: A (Shor & Orne, 1962) or a rationale that presented hypnosis as a nondeceptive placebo, consistent with Kirsch's (1994) sociocognitive perspective of hypnosis. The effects of the placebo and standard rationales were highly comparable with respect to hypnotic attitudes; prehypnotic expectancies; objective, subjective, and involuntariness measures of hypnotic responding; as well as a variety of subjective experiences during hypnosis, as measured by the Phenomenology of Consciousness Inventory (Pekala, 1982). Differences among correlations were not evident when measures were compared across groups. However, indices of hypnotic responding were correlated with attitudes in the hypnosis but not the placebo condition, and, generally speaking, the link between subjective experiences during hypnosis and measures of hypnotic responding were more reliable in the placebo than the hypnosis group. Researcher findings are neutral with respect to providing support for altered state versus sociocognitive models of hypnosis.