Procedural memory in dissociative identity disorder: When can inter-identity amnesia be truly established?

• Published in: Consciousness and cognition 2005-06, Vol.14 (2), p.377-389
• Main Authors: Huntjens, Rafaële J.C., Postma, Albert, Woertman, Liesbeth, van der Hart, Onno, Peters, Madelon L.
• Format: Article
• Language: English
• Subjects: Adult and adolescent clinical studies; Amnesia - diagnosis; Amnesia - physiopathology; Biological and medical sciences; Diagnostic and Statistical Manual of Mental Disorders; DID; Dissociation; Dissociative Disorders - diagnosis; Dissociative Disorders - physiopathology; Female; Humans; Inter-identity amnesia; Medical sciences; Memory; Miscellaneous; Procedural memory; Psychology. Psychoanalysis. Psychiatry; Psychopathology. Psychiatry; Reaction Time; Severity of Illness Index
• ISSN: 1053-8100; 1090-2376
• DOI: 10.1016/j.concog.2004.10.001

In a serial reaction time task, procedural memory was examined in Dissociative Identity Disorder (DID). Thirty-one DID patients were tested for inter-identity transfer of procedural learning and their memory performance was compared with 25 normal controls and 25 controls instructed to simulate DID. Results of patients seemed to indicate a pattern of inter-identity amnesia. Simulators, however, were able to mimic a pattern of inter-identity amnesia, rendering the results of patients impossible to interpret as either a pattern of amnesia or a pattern of simulation. It is argued that studies not including DID-simulators or simulation-free memory tasks, should not be taken as evidence for (or against) amnesia in DID.