• Forty schizophrenic outpatients and 40 normal subjects were assessed using extensive clinical (eg, Brief Psychiatric Rating Scale, Scale for the Assessment of Negative Symptoms and Scale for the Assessment of Positive Symptoms) and neuropsychological (extended Halstead-Reitan Battery) measures. The schizophrenic patients had multiple neuropsychological deficits on tests of complex conceptual reasoning, psychomotor speed, new learning and incidental memory, and both motor and sensory-perceptual abilities. Neuropsychological impairment correlated more strongly with negative than positive symptoms. Overall, the schizophrenic outpatients showed relatively modest increases in the number of perseverative responses on the Wisconsin Card Sorting Test of abstraction flexibility. A subgroup of these schizophrenic patients seemed to be particularly impaired on the Wisconsin Card Sorting Test. This pattern of results, in conjunction with previous studies, supports the idea that, while some schizophrenic patients may have fixed, frontally based dysfunctions, these dysfunctions may be most prominent, and even fixed, in deteriorated, kraepelinian patients. These data provide evidence for diffuse and far-reaching deficits in a majority of outpatients with chronic schizophrenia.
Braff DL, Heaton R, Kuck J, Cullum M, Moranville J, Grant I, Zisook S. The Generalized Pattern of Neuropsychological Deficits in Outpatients With Chronic Schizophrenia With Heterogeneous Wisconsin Card Sorting Test Results. Arch Gen Psychiatry. 1991;48(10):891-898. doi:10.1001/archpsyc.1991.01810340023003