Cognitive function in schizoaffective disorder and clinical subtypes of schizophrenia.

Cognitive studies of patients with Schizoaffective Disorder typically indicate that the cognitive function of these patients resembles that of patients with Schizophrenic Disorder more than it does patients with nonpsychotic Mood Disorder. In this study patients with Schizoaffective Disorder were compared with patients with Paranoid, Undifferentiated and Residual clinical subtypes on a number of measures of cognitive function. Multivariate analyses of variance indicated that the cognitive function of Schizoaffective and Paranoid patients had more intact cognitive function that did Undifferentiated and Residual patients. Application of cluster analysis indicated that there were relative high percentages of Schizoaffective and Paranoid patients in a "Neuropsychologically Normal" cluster. It was concluded that Schizoaffective Disorder as well as other clinical subtypes of schizophrenia are cognitively heterogeneous, and it was suggested that a subgroup of patients with Schizoaffective Disorder may not differ in cognitive ability from patients with nonpsychotic Mood Disorder.