Suggested posthypnotic amnesia in psychiatric patients and normals.

The present study examined both quantitative and qualitative hypnotizability differences among four psychiatric patient groups (dissociative disorder (n = 17), schizophrenic (n = 13), mood disorder (n = 14), and anxiety disorder (n = 14) patients), and normals (college students (n = 63). Dissociative disorder patients earned significantly higher corrected total scores on the Stanford Hypnotic Susceptibility Scale, Form C (mean = 7.94), than all other groups. Likewise, dissociative disorder patients initially recalled significantly fewer items when the posthypnotic amnesia suggestion was in effect (mean = .41) and reversed significantly more items when the suggestion was canceled (mean = 3.82) than all other groups. In contrast, schizophrenic patients recalled significantly fewer items when the amnesia suggestion was in effect (mean = 1.85) and reversed significantly fewer items when it was canceled (mean = .77) than the remaining groups. This qualitative difference between schizophrenic patients and the other groups on the suggested posthypnotic amnesia item was observed even though there were no significant quantitative differences between groups in overall hypnotic responsivity.