Failure to Replicate Evoked Potential Observations Suggesting Corpus Callosum Dysfunction in Schizophrenia

Abstract

SummarySomatosensory potentials (SEPs) evoked by vibrotactile finger stimulation have been reported to be the same in both hemispheres in schizophrenics, whereas they are asymmetrical in normals, with the contralateral hemisphere leading the ipsilateral (Jones and Miller, 1981). These findings were taken to indicate that the corpus callosum is nonfunctional in schizophrenics. To attempt replication of these results, vibrotactile SEPs of 6 schizophrenics and 6 normal controls were recorded with both bipolar and monopolar derivations. Assymetrical bipolar SEPs were obtained in both schizophrenics and controls; previous observations of schizophrenic-control differences were not replicated. Acceptable evidence of ipsilateral early SEPs was not obtained; the test procedure seems inappropriate for measuring callosal conduction time.