The Neural Substrates of Motor Recovery After Focal Damage to the Central Nervous System

Brain activation patterns for a single stroke patient with extensive right-hemisphere subcortical damage 6 months poststroke (front of the brain is at the top of the figure). The patient had made a moderate recovery (Barthel Index score, 20/20; Action Research Arm Test score, 57/57; grip strength 64% of unaffected side; 9-hole peg test score 15% of unaffected side). (A) Brain activity in the hand area of left primary motor cortex during the performance of unaffected right hand grips. (B) Brain activity in left primary motor cortex and other regions (including premotor cortex and supplementary motor area) during the performance of affected left hand grips. Analysis performed using Statistical Parametric Mapping.^a Voxels are significant at P<.05 (corrected for multiple comparisons across whole brain). Brain activity is overlayed onto patient’s own normalized structural T1-weighted MRI scan. The regions involved in movement of the normal right hand are minimal in comparison to the extensive network involved during movement of the recovering left hand. Note that movement of either hand is associated with activity predominantly in the left side of the brain. Abbreviations: CS, central sulcus; L, left; R, right.