A Comparison of Posthypnotic Amnesia and the Simulation of Amnesia through Brain Injury

Although the phenomenon of posthypnotic amnesia has been invoked in many applied contexts, its academic status remains unclear. This paper examines the claim that hypnotic amnesia and amnesia due to brain injury may share similarities in that, in both, implicit memory is spared. Hypnotically susceptible participants given an hypnotic suggestion for amnesia were compared to untreated controls and participants simulating amnesia on two memory tests, fragment completion and the coin in the hand test. As brain injured patients with amnesia typically perform better than simulators on these tests, it has been proposed that both may be useful for the detection of malingering in clinical contexts. On both tests, participants of high and medium hypnotic susceptibility performed similarly to simulators showing deficits in implicit memory not typically shown by brain injured patients. It is concluded that the results are most compatible with a response suppression account of hypnotic amnesia.