Recall and recognition memory during posthypnotic amnesia: a failure to confirm the disrupted-search hypothesis and the memory disorganization hypothesis.

Recent research has led some investigators to hypothesize that posthypnotic amnesia is characterized by a disruption in the memory search process and, more generally, by disorganization in memory retrieval. Data to test these hypotheses were provided by 141 male and female undergraduates administered the Stanford Hypnotic Susceptibility Scales, Forms B and C. Amnesia was assessed by the usual recall criterion and by a batch recognition-testing procedure. The disruptedsearch hypothesis, tested by comparing the effects of the amnesia suggestion on recall and recognition, was not supported. The use of recognition items, rank ordered by subjects according to their judgment of order of administration, furnished data to test the memory disorganization hypothesis. In support of this hypothesis, analyses of the temporal rankings of recognized items revealed greater disorganization in the memory of subjects who were initially amnesic by recall criteria than those who were partially amnesic or nonamnesic. Nevertheless, a number of other findings, including the fact that fewer than 50% of the initially amnesic subjects showed disorganized recognition and that the disorganization effect during recall was weak and inconsistent, call into question the explanatory power of this hypothesis.