Personality dysfunction and lateralized deficits in cerebral functions as measured by the MMPI and Reitan-Halstead Battery.

Previous research using the MMPI has failed to show personality differences between right and left hemispheric brain-damaged patients. The purposes of the present study were, first to determine whether lateralized deficits in cortical functioning as measured by neuropsychological testing are systematically associated with neurotic-psychotic distinctions on the MMPI. Secondly, we wished to determine the strength of predictive association in the relationship between lateralized functional deficits and personality organization. A localization key (Russell, et al., 1972) was applied to the "Reitan-Battery" test results for 94 patients who were referred for neuropsychological testing. Based on this approach, 15 pairs of patients were selected who were "left" or "right" hemispheric dysfunctional in terms of test performance. Pairs were matched for age and "average impairment rating" (Russell, et al., 1972). Their MMPIs were also designated "neurotic" or "psychotic" using the Goldberg Psychotic Index (Goldberg, 1972). The results suggest that patients with deficits in left hemisphere functions tend to score in the psychotic range and patients with deficits in right hemispheric functions tend to score in the neurotic range of the MMPI Goldberg Index. In this set of data there was a 38% reduction in error of predicting neurotic-psychotic category but knowing whether the patient was left or right hemispheric dysfunctional in terms of neuropsychological tests.