Spontaneous and suggested posthypnotic source amnesia.

Abstract

Abstract The occurrence of spontaneous and/or suggested posthyp-notic source amnesia was investigated in a sample of 93 introductory psychology students. Ss were randomly assigned to one of two groups, and served as Ss on 2 successive days. The standard induction of the Stanford Hypnotic Susceptibility Scale, Form C (SHSS:C) was utilized. Modified items from SHSS:C as well as a source amnesia item were presented. For one group, source amnesia was suggested on one day and was not suggested on the second day. This order was reversed for the second group. 2 Ss (2%) showed spontaneous source amnesia on one of the two days and a significantly larger number, 8 (9%), showed suggested source amnesia. With a less rigid criterion of scoring source amnesia, the frequency of spontaneous source amnesia increased to 15% and suggested source amnesia to 11%. When the groups were subdivided on the basis of susceptibility scores: (a) there was little effect of source amnesia below a susceptibility score of 4, and (b) both spontaneous and suggested source amnesia increased as hypnotic susceptibility increased. Spontaneous source amnesia correlated .57 with susceptibility, and suggested source amnesia, .34 with susceptibility. A correlation of .48 was found between recall amnesia and spontaneous source amnesia and .49 between recall amnesia and suggested source amnesia.