Do stroke patients re-learn motor performance?
Current models of motor learning suggest that during early learning, there is a dynamic interaction between a frontoparietal network encoding movement in terms of spatial coordinates, that requires high levels of attention, and motor cortex which encodes movement in terms of a kinematic system of joints, muscles, limb trajectories, etc. Motor cortex is dominant once learning has occurred and a movement has become automatic (Hikosaka et al., 2002). Each of these cortical systems is engaged in loops that include different regions of cerebellum and basal ganglia. Attempted movements by hemiparetic patients will result in significant discrepancies between predicted and actual performance, generating error signals that in normal subjects are used by the cerebellum to optimize subsequent sensorimotor accuracy (Blakemore et al., 2001). Interactions between these parallel systems occur not only in cerebellum and basal ganglia, but also via intracortical connections involving particularly premo
