POSTLESIONAL PLASTICITY OF THE HUMAN CERE BRAL-CORTEX .2.

To investigate the mechanisms of functional recovery in the human brai n neuroactivation studies were performed in patients with focal brain lesions. Measurements of the regional cerebral blood flow provided evi dence for a shift of activation areas into intact cortex adjacent to t he damaged cortex in chronic brain lesions of the motor cortex and its output system. In addition, auxiliary activation areas were found to become engaged as similarly observed during implicit learning of manua l skills. It is hypothesized that postlesional neuroplasticity is medi ated by adaptive re-learning. Finally, evidence was obtained suggestin g that restitution of motor skills after complete damage of their cort ical representation can take place by substitution through homologue a reas in the contralateral cerebral hemisphere. Successful rehabilitati on seems to be an active cerebral process.