Failure of dominant left-hemispheric activation to right-ear stimulation in schizophrenia

Schizophrenia is associated with an absence of the lateralizations that typify the human brain. Previous evidence emphasized structural changes, particularly reduced asymmetry in extension and surface of the planum temporale, although gross structural deviations occur only in a minority of patients. The present study describes an absence of lateralization on a robust functional measure that characterized schizophrenia patients: healthy subjects but not schizophrenics displayed a contralateral left-hemispheric dominance of the auditory evoked magnetic field to right-ear auditory stimulation. Absence of contralateral dominance in response to auditory stimuli among schizophrenia patients may indicate a failure to establish unequivocal left-hemispheric dominance of the phonological loop as hypothesized by Crow.