RECOVERY FROM MOTOR STROKE - HUMAN POSITRON EMISSION TOMOGRAPHY STUDIES

Three major studies have investigated the reorganisation of the human motor system after stroke by measuring changes in regional cerebral blood flow during defined tasks with positron emission tomography. The results imply that there is considerable scope for functional plasticity in the adult human brain. Changes in both the damaged and the undamaged hemisphere can be observed. The pattern of reorganisation differs in individual patients, depending on the location of the lesion. While substitution of function in homologous brain regions of the undamaged hemisphere may occur in some patients, redistribution of activity within a widespread network of parallel-acting multiple motor areas and pathways constitutes the central mechanism in motor recovery.