NEURAL SUBSTRATES FOR THE EFFECTS OF REHABILITATIVE TRAINING ON MOTORRECOVERY AFTER ISCHEMIC INFARCT

Substantial functional reorganization lakes place in the motor cortex of adult primates after a focal ischemic infarct, as might occur in st roke. A subtotal lesion confined to a small portion of the representat ion of one hand was previously shown to result in a further loss of ha nd territory in the adjacent, undamaged cortex of adult squirrel monke ys. In the present study, retraining of skilled hand use after similar infarcts resulted in prevention of the loss of hand territory adjacen t to the infarct. In some instances, the hand representations expanded into regions formerly occupied by representations of the elbow and sh oulder. Functional reorganization in the undamaged motor cortex was ac companied by behavioral recovery of skilled hand function. These resul ts suggest that, after local damage to the motor cortex, rehabilitativ e training can shape subsequent reorganization in the adjacent intact cortex, and that the undamaged motor cortex may play an important role in motor recovery.