Schizophrenia and the corpus callosum: developmental, structural and functional relationships.

Several empirical and theoretical connections exist between schizophrenia and the corpus callosum: (1) disconnection symptoms resemble certain psychotic phenomena; (2) abnormal interhemispheric transmission could explain typically schizophrenic phenomena; (3) cases of psychosis have been found in association with complete and partial agenesis of the callosum; (4) experimental neuropsychology with schizophrenic patients has revealed abnormal patterns of interhemispheric transfer; (5) studies using magnetic resonance imaging have shown abnormal callosal dimensions in schizophrenic patients. The evidence in support of these links is discussed critically. Novel neuropsychological approaches in the study of information transfer in the visual modality between the cerebral hemispheres, consistent with callosal hyperconnectivity in schizophrenic patients but not matched psychiatric controls are highlighted. Some suggestions for further work including integrating functional and structural measures are offered.