Inferior Parietal Region Implicated in Neurocognitive Impairment in Schizophrenia

To the Editor.— Berman et al,1 in the July 1988 issue of the Archives, demonstrated increased cerebral blood flow in posterior cortical regions of both schizophrenic subjects and control subjects while they were performing the Raven's Progressive Matrices task. Cerebral blood flow in the two groups did not differ significantly. In contrast, schizophrenics' failure to activate the dorsolateral prefrontal cortex while doing the Wisconsin Card …