Intellectual functioning of inpatients with dissociative identity disorder and dissociative disorder not otherwise...

The intellectual functioning of 105 inpatients with multiple personality disorder and dissociative disorder not otherwise specified was assessed using the Wechsler Adult Intelligence Scale-Revised as part of a comprehensive research protocol. There were no significant intellectual differences between the groups on any major intelligence quotient summary score or any of the age-adjusted empirical factor scores. The anecdotal but widely accepted hypotheses that dissociative patients either have above average premorbid intelligence or that their current intellectual functioning is deleteriously affected by their fluctuant psychiatric disorder were not supported in this sample. A significant subsample of the multiple personality disorder group manifested abnormal interest scatter on the Wechsler Adult Intelligence Scale-Revised verbal subtests, and this variability was attributed to subtle neuropsychological deficits on the Memory/Distractibility factor. We speculate that dissociative patients might need to be evaluated for attention deficit disorder in addition to the range of dissociative symptoms in a comprehensive evaluation.