Self-report measures of hypnotic depth

Abstract

The purpose of the study was to investigate the use of self-report measures of hypnotic depth in group settings. Earlier studies (O'Connell, 1964; Tart, 1970) had indicated that Ss were able to give estimates of their depth of hypnosis which were significantly correlated with indices of behavioral and subjective responsiveness to hypnotic suggestions. While these self-report scales seemed to have promise as quick and convenient measures of S's degree of involvement in hypnosis, there were several remaining questions concerning their validity, bases, and range of applicability. The major questions with which the present study was concerned were the validity of these measures, the feasibility of using written self-reports in group settings, the development of new measures of hypnotic processes, and the relation between self-reports of depth and the dimensions of hypnotic depth described by Shor (1959, 1962). The Ss in the research were undergraduate students seen in groups of two to 40. They used an 11-point scale to estimate their depth .of hypnosis at various points in the experimental sessions. Criterion measures included a modified form of the Harvard Group Scale of Hypnotic Susceptibility (Shor & Orne, 1962), Field's Inventory (Field, 1965), and a scale designed to reflect intensity of subjective reaction to hypnotic suggestions. Seven measures were developed in an attempt to assess Shor's three dimensions of hypnotic depth. Results of the present study indicated that only two of these measures (estimates of awareness of the external environment and retrospective ratings of degree of conscious control over one's behavior) had merit as potential scales for Sher's dimensions. The results of the present study support the conclusion that written state-reports (SRs) obtained in group settings are comparable to spoken SRs obtained individually. Further, there was no evidence that the SR methodology used in the study tended to disrupt hypnotic processes. While the results indicated that Ss used their observed performance on the criterion measures as one basis for making SRs, validity coefficients computed for SRs produced prior to the administration of the criterion measures were of sufficient magnitude to justify the use of SRs as an independent measure of hypnotic depth in group settings. The correlations between SR scores and measures of Sher's dimensions suggested that the experiential reactions described by Shor may have been important bases for SRs. The measure developed to assess Shor's trance dimension, a self-report scale of S's awareness of the outer environment, appeared to have potential as an independent measure of hypnotic depth and as a method of assessing experiential aspects of other altered states of consciousness.