Psychopathology, hypnotizability, and dissociation

Objective: The purpose of the study was to replicate and extend previous findings regarding the hypnotizability of different clinical groups. Method: The authors compared the differential hypnotizability of four psychiatric groups - patients with dissociative disorders (N=17), schizophrenia (N=13), mood disorders (N=13), and anxiety disorders (N=14)-and one normal group of college students (N=63). Hypnotizability was assessed by four different measures: the eye roll sign and the induction score of the Hypnotic Induction Profile, the Stanford Hypnotic Susceptibility Scale, Form C, and two self-ratings of hypnotizability. Results: As predicted, dissociative disorder patients had significantly higher hypnotizability scores on all measures than all other groups. Schizophrenic patients, on the other hand, had significantly lower scores than normal subjects on the eye roll sign and induction score but not on the other measures of hypnotizability. Some other unpredicted between-group differences were also found. Nevertheless, despite the between-group differences, the intercorrelations between the various hypnotizability measures within the normal group were very similar to those observed in the combined patient groups. Conclusions: The findings suggest that routine hypnotizability assessment may be useful in the differential diagnosis of patients with dissociative disorders.