The Effect of Manipulated Expectancies on Posthypnotic Amnesia

The effects of manipulated S expectancy and direct suggestions for amnesia on posthypnotic amnesia were assessed. 120 undergraduate students were randomly assigned to 6 groups: negative expectancy (for amnesia)/suggestions (for amnesia); no expectancy/suggestions; negative expectancy/no suggestions; no expectancy/no suggestions; and 2 control groups. The results indicated that the expectancy manipulation had no effect on the Occurrence of posthypnotic amnesia measured by the Stanford Hypnotic Susceptibility Scale, Form A (Weitzenhoffer & Hilgard, 1959), whereas suggestions for amnesia were found to have a significant effect. Hypnotized suggestion and no suggestion Ss remembered significantly less than Ss in the nonhypnotized control groups. The implications of the findings were discussed.