Volitional and Nonvolitional Responses to Hypnotic Suggestions: Predictors and Subjective Experience

This investigation combined the data from two studies that used modified scoring of the Harvard Group Scale of Hypnotic Susceptibility (Shor & Orne, 1962) to evaluate deliberate, volitional responses to suggestions. One study also employed subjective ratings of each item of the Harvard Scale, with comparisons of nonvolitional, volitional, and non-responses. Based on the assumption that participants would have marked volitional responses as positive responses using the traditional scale, the traditional scoring method was found to inflate mean hypnotic responsiveness by nearly one point. Two hypothesized correlates of hypnotic performance, rapport with the hypnotist and a phenomenological measure of hypnosis, increased significantly when volitional responses were taken into account. The way in which participants were recruited did not predict volitional responses, but individuals who reported deliberate responses to suggestions from the Harvard Scale were less likely to express willingness to participate in future studies. Some of the volitional responses to the items were rated as subjectively more real compared to no responses, though nonvolitional responses were rated as the most real compared with compliance responses and no responses for all items. More difficult items were more likely to be performed volitionally than easier items. It is suggested that future studies using hypnotic inventories account for volitional responses. The nature of deliberately produced responses should also be examined using qualitative and quantitative data, especially with respect to how a given suggestion may affect the execution of the volitional behavior.