Memory, Amnesia, and Dissociative Identity Disorder
Virtually all patients with dissociative identity (or multiple personality) disorder manifest interpersonality amnesia, whereby events experienced by a particular personality state or identity are retrievable by that same identity but not by a different one Though considered a hallmark of dissociative identity disorder (DID), interpersonality amnesia has to date attracted little empirical attention. Further, the few studies on the topic typically include just 1 DID patient and a single index of retention In contrast the current experiment involved 9 DID patients and several measures of either explicit or implicit memory Replicating and extending the single-case study of Nissen, Ross, Willingham, MacKenzie, and Schacter (1988), the present results revealed that implicit testing is a necessary but not a sufficient condition for demonstrating transfer of information from one identity to another Specifically, whereas priming in word-stem completion occurred only if the same personality state performed at both study and at test, priming in picture-fragment completion was as robust between different identities as it was within the same identity Discussion focuses on prospects for future research aimed at understanding the nature and scope of interpersonality amnesia