This study compared patients across 5 psychiatric diagnostic groups: Depression, Mania, Schizophrenia, Schizoaffective Disorder, and Psychosis NOS, all of whom are psychotic. Differences in overall cognitive profiles and in dysfunctional memory mechanisms, as well as the effect of psychosis on cognitive functioning were explored using the Neurobehavioral Cognitive Status Examination (NCSE), a brief screening instrument. Results indicated pronounced deficit in memory and abstract reasoning associated with schizophrenic illness, which is not secondary to psychosis and points to localized brain dysfunction. Both encoding and postencoding memory mechanisms were affected. Results support a hypothesis of progressive dysfunction associated with the severity and chronicity of the illness. Implications of findings in aiding diagnostic determination, patient management and rehabilitation are discussed.
The pattern of cognitive and intellectual impairment associated with schizophrenia has been of interest to researchers since original description of this disorder by Kraepelin (1913) as "dementia praecox." Gradual decline in IQ, poor overall performance on neuropsychological batteries, and progressive dementing syndrome in schizophrenic patients were repeatedly reported in the literature (Aylward, Walker, &