"How deeply hypnotized did i get?" Predicting self-reported hypnotic depth from a phenomenological assessment instrument.

Procedures for estimating hypnotic depth have been used for more than 70 years. This study predicted self-reported hypnotic depth from the phenomenological and behavioral variables of the Phenomenology of Consciousness Inventory-Hypnotic Assessment Procedure (PCI-HAP). Participants were divided into 2 groups; 1 was used to generate regression equations, and the other group was used for cross-validation. Both imagery vividness during hypnosis (imagoic suggestibility) and the PCI pHGS measure of hypnotic depth (hypnoidal state) accounted for most of the variance in self-reported hypnotic depth. The above results, further supported by correlational and 3-D visual analyses, are consistent with other researchers' observations that ratings of hypnotic depth are a function of: (a) alterations in subjective experience, and (b) the perception of responsiveness to suggestions. The findings are also congruent with J. Holroyd's hypothesis that suggestibility and altered-state effects interact to produce hypnotic effects.