SENSORIMOTOR CORTEX AND SUPPLEMENTARY MOTOR AREA CHANGES IN SCHIZOPHRENIA - A STUDY WITH FUNCTIONAL MAGNETIC-RESONANCE-IMAGING

Background. Neurological soft signs (NSS) such as a disturbed finger-t o-thumb opposition are frequently found in schizophrenia. To identify the underlying cerebral changes we investigated sensorimotor cortex an d supplementary motor area (SMA) activation during finger-to-thumb opp osition using functional magnetic resonance imaging (fMRI). Method. Te n DSM-III-R schizophrenics and seven healthy controls were included. A ll subjects were right-handed. fMRI was carried out in a resting condi tion followed by an activation state (finger-to-thumb opposition) and the activities in the sensorimotor cortices and SMA recorded. Results. All subjects showed a significant activation of the SMA and both ipsi lateral and contralateral sensorimotor cortices. In the controls, ipsi lateral finger-to-thumb opposition was associated with a greater left than right hemispheric sensorimotor cortex coactivation. When compared with the healthy controls, the schizophrenic patients showed a decrea sed activation of both sensorimotor cortices and SMA, as well as a rev ersed lateralisation effect. Conclusion. Sensorimotor cortex and SMA d ysfunction are associated with motor disturbances in schizophrenia.