A NEUROPSYCHOLOGICAL STUDY OF PREFRONTAL LOBE FUNCTION IN THE POSITIVE AND NEGATIVE SUBTYPES OF SCHIZOPHRENIA

The symptoms of schizophrenia are frequently divided into positive and negative subtypes. It has been suggested that the negative symptoms a re similar to those seen with prefrontal lobe cortical dysfunction. Se veral neuropsychological investigations of that hypothesis have been c arried out, but none have directly compared a negative symptom group w ith a positive symptom group on the same test battery. In the present study, the Positive and Negative Syndrome Scale (PANSS; Kay, Fiszbein, & Opler, 1987) was used to distinguish two groups of 20 patients with schizophrenia with predominant positive or negative symptoms. A batte ry of 7 neuropsychological tests considered capable of isolating prefr ontal lobe dysfunction was administered. A significant group differenc e was noted on 6 of the tests; the negative symptom group performed mu ch worse than the positive symptom group. The results of this study su pport the hypothesis that a relationship exists between the negative s ymptoms of schizophrenia and prefrontal lobe dysfunction.