Chronic interictal psychotic syndromes, often resembling schizophrenia, develop in some patients with epilepsy. Although widespread brain abnormalities are recognized as characteristic of schizophrenia, prevailing but controversial hypotheses on the co-occurrence of epilepsy and psychosis implicate left temporal lobe pathology. In this study, quantitative MRI methods were used to address the regional specificity of structural brain abnormalities in patients with epilepsy plus chronic interictal psychosis (E + PSY, n = 9) relative to three comparison groups: unilateral temporal lobe epilepsy without chronic psychosis (TLE, n = 18), schizophrenia (SCZ, n = 46), and healthy control subjects (HC, n = 57). Brain measures, derived from a coronal spin-echo MRI sequence, were adjusted for age and cerebral volume. Relative to HC, all patient groups had ventricular enlargement and smaller temporal lobe, frontoparietal, and superior temporal gyrus gray matter volumes, with the extent of these abnormalities greatest in E + PSY. Only TLE had temporal lobe white matter deficits, as well as smaller hippocampi, which were ipsilateral to the seizure focus. Structural brain abnormalities in E + PSY are not restricted to the left temporal lobe. The confluence of cortical gray matter deficits in E + PSY and SCZ suggests salience to chronic psychosis.
Bibliographical noteFunding Information:
Support was provided by the Theodore and Vada Stanley Foundation, Epilepsy Foundation of America, NIH [Grants MH53485, MH30854 and MH58007, Human Health Services Grant M01-RR00070, General Clinical Research Centers, National Center for Research Resources], the Katherine D. McCormick Fund for Women, the Norris Foundation, and the Department of Veterans Affairs. We also thank Drs M. Risinger and E. Bush for referring and diagnosing epilepsy subjects; S. Dement, T. Sung, S. Spears, H. Freeman, and A. Marie for recruitment and/or image analysis; Dr G. Murphy for neuroanatomical consultation; Dr B. Lane for neuroradiological expertise; and Dr B.W. Brown for statistical advice. These data were reported in part at the Seventh International Congress on Schizophrenia Research, Santa Fe, NM (April, 1999) and the Society of Biological Psychiatry Annual Meeting (May, 1999).
- Temporal lobe