Maintenance of training effects on the Wisconsin Card Sorting Test by patients with schizophrenia or affective disorders.

The authors used the Wisconsin Card Sorting Test to study 50 hospitalized psychiatric patients: 28 with schizophrenia, 17 with affective disorders, and five with schizoaffective disorder. The schizophrenic patients performed significantly more poorly than the patients with affective disorders. Both groups of patients improved when given additional instructions. The schizophrenic patients maintained their improvement when retested approximately 6 weeks later. The results suggest that factors other than frontal cortex dysfunction are involved in schizophrenic patients' performance on the Wisconsin Card Sorting Test.