Abstract
Members of a birth cohort were assessed for psychopathology and neuropsychological dysfunction at age 13. Ss who met DSM-III criteria for a single disorder, multiple disorders, and no disorder were compared on 5 composite neuropsychological measures. The multiple disorders group performed significantly worse than did the nondisordered group on the Verbal, Visuospatial, Verbal Memory, and Visual-Motor Integration factors. They also showed the highest rate of neuropsychological impairment. The attention-deficit disorder group performed significantly worse than did the nondisordered group on the Verbal Memory and Visual-Motor Integration factors, and the anxiety disorder group performed significantly worse than did the nondisordered group on the Visual-Motor Integration factor. Results suggest that neuropsychological dysfunction is more often associated with multiple rather than single, psychiatric disorders in adolescents. The problem of comorbidity in studies of neuropsychological function in childhood and adolescent psychopathology is highlighted.