Schizencephaly associated with psychosis.

Schizencephaly is a rare disorder of brain development resulting in the formation of abnormal unilateral or bilateral clefts in the cerebral hemispheres. It is often accompanied by partial seizures, mental retardation, and hemiparesis. Two patients are described with clear psychotic symptoms with either unilateral or bilateral schizencephaly. The implications of the association between schizencephaly and psychosis in these patients for understanding the biology of the psychoses are discussed.