MEDIAL AND SUPERIOR TEMPORAL GYRAL VOLUMES AND CEREBRAL ASYMMETRY IN SCHIZOPHRENIA VERSUS BIPOLAR DISORDER

Prior magnetic resonance imaging (MRI) studies report both medial and lateral cortical temporal changes and disturbed temporal lobe asymmetr ies in schizophrenic patients compared with healthy controls. The spec ificity of temporal lobe (TL) changes in schizophrenia is unknown. We determined the occurrence and specificity of these TL changes. Forty-s ix schizophrenic patients were compared to 60 normal controls and 27 b ipolar subjects on MRI measures of bilateral volumes of anterior and p osterior superior temporal gyrus (STG), amygdala, entorhinal cortex, a nd multiple medial temporal structures, as well as global brain measur es. Several regional comparisons distinguished schizophrenia fr om bip olar disorder. Entorhinal cortex, not previously assessed using MRI in schizophrenia, was bilaterally smaller than normal in schizophrenia b ut not in bipolar disorder. Schizophrenic but not bipolar patients had an alteration of normal posterior STG asymmetry. Additionally, left a nterior STG and right amygdala were smaller than predicted in schizoph renia but not bipolar disorder. Left amygdala was smaller and right an terior STG larger in bipolar disorder but not schizophrenia. (C) 1997 Society of Biological Psychiatry.