Neuroleptic effects on interhemispheric and intrahemispheric performance of tactile discrimination tasks by...

The contribution of neuroleptic medication to impaired interhemispheric integration of information, and the relationship between the apparent interhemispheric failure and a unilateral dysfunction, were examined in 12 acutely psychotic patients. The patients performed tactile discrimination tasks, under conditions of intrahemispheric and interhemispheric presentation, before the introduction of any antipsychotic medication, and again after a period of treatment with neuroleptics. In unmedicated patients, both unilateral left hemispheric and interhemispheric deficits were found. However, whereas treatment with neuroleptics normalized the unilateral left hemispheric deficit, it did not have any effect on the performance of the interhemispheric tasks. These findings suggest that the impairment in interhemispheric integration is independent of the unilateral dysfunction and is not modulated by treatment with neuroleptics.