The neuropsychology of schizophrenia : is there evidence for a neuropsychologically impaired subgroup?

This study explores the relationship between schizophrenic symptoms and patterns of neuropsychological functioning. Fifty- nine Ss who met DSM-III criteria for schizophrenia were evaluated using Andreasen's Scales for the Assessment of Positive Symptoms and the Scale for the Assessment of Negative symptoms. Twenty-five Ss had marked positive symptoms only, 14 had marked negative symptoms only, and 20 had marked mixed symptoms. All Ss were given a neuropsychological evaluation which included the examination of general intellectual functioning (WAIS, short form); memory (Wechsler Memory Scale, Russell variation); language (Token Test; Controlled Word Association Test; Aphasia Screening Test, verbal score; delayed auditory feedback); higher cognitive functioning (Trail Making Test, Parts A and B); psychomotor ability (Finger Oscillation); visuo-spatial functioning; tactile, visual, and auditory perception. Although 17 of the 59 Ss evidenced neurological impairment by scoring below cutoff norms on four or more of the eight areas examined, univariate and multivariate analyses failed to reveal any significant differences between the patient groups in neuropsychological functioning. The data does not support a meaningful distinction between positive, negative, and mixed schizophrenic subtypes as defined by Andreasen's scales with respect to neuropsychological performance.