Does Hypnotic Amnesia Dissipate with Time?

Abstract

Two interrelated experiments investigated the hypothesis that hypnotic amnesia dissipates “spontaneously” over time. After the administration of a hypnotic amnesia suggestion for a previously learned word list, Retest subjects in Experiment 1 received two successive recall challenges before cancellation of the suggestion. Delay subjects received only one challenge. It occurred at the same time that Retest subjects received their second challenge. No differences in amount of amnesia were found between the Delay trial and either of the Retest trials, thereby failing to provide support for the dissipation hypothesis. Experiment 2 manipulated subjects' expectations concerning the amount of amnesia typically shown on a second challenge. Subjects in the “Remember More” or “Remember Less” conditions were led to believe that they would recall either more or less critical material on the second amnesia challenge. Both Retest (no expectancy) and Remember More subjects recalled significantly more words on the second challenge than on the first. However, a significantly greater proportion of Remember More subjects than Retest subjects showed recall increments on the second challenge. Remember Less subjects showed no significant difference in the amount recalled on the two challenges. These results do not support the dissipation hypothesis of hypnotic amnesia. Instead, they are consistent with theoretical accounts of amnesia as a strategic enactment carried out by subjects in response to the unfolding social demands of the testing situation.