Neuropsychological deterioration and CT scan findings in chronic schizophrenia

Structural abnormalities of the brain, particularly ventricular enlargement and prominence of cortical sulci, have been documented reliably in CT scan investigations of chronic schizophrenic patients. Although the clinical significance of these findings is still obscure, neuropsychological (NP) deficits have emerged as relatively robust correlates of the structural anomalies. Unfortunately, it remains unknown whether the previous findings of NP impairment in association with CT scan abnormalities reflect poor premorbid abilities or deterioration from previously higher levels. This study involved administration of an extensive NP battery and CT scans in a chronic schizophrenic sample. In addition to global and specific scales of NP functions, indices of premorbid ability and deterioration were also employed. The results are consistent with the hypothesis that CT scan findings are associated more with deterioration of functioning than with global measures of NP dysfunction or poor premorbid ability. Conversely, the findings suggest that in patients with normal scans, NP morbidity may be a consequence of failure in the acquisition of a normal cognitive repertoire.