Hand Motor Recovery after Stroke: A Transcranial Magnetic Stimulation Mapping Study of Motor Output Areas and Their Relation to Functional Status

The respective contributions of the stroke and undam-aged hemispheres to motor recovery after stroke remains controversial. The aim of this article is to evaluate the relationship between location and size of cortical motor areas and outcome after stroke. Twelve controls and 12 stroke patients were studied. Hand cortical motor output areas were determined using transcranial magnetic stimulation. Motor-evoked potentials were recorded simultaneously from both hands. Functional motor abili-ties were evaluated using well-validated measures. Surface area, weighted surface area, and center of grav-ity of motor output areas were calculated. Different pat-terns of motor output areas to the paretic hand were observed; there was no motor output from the stroke hemisphere in patients with poor outcome, contrasting t