No evidence of a homogeneous frontal neuropsychological profile in a sample of schizophrenic subjects.

The authors obtained a frontal functions profile for 81 schizophrenic patients using six neuropsychological tests that evaluate the dorsolateral prefrontal cortex functions, i.e., working memory, executive functions, and strategic performance. They then analyzed the test performances with a cluster analysis, which produced a four-cluster solution. The results support the hypothesis that neuropsychological dysfunctions in schizophrenia are heterogeneous. The performances on many of the neuropsychological tests were also strongly correlated with verbal and nonverbal IQ, as measured by the Wechsler Adult Intelligence Scale-Revised.