THE CORTICAL TOPOGRAPHY OF HUMAN SWALLOWING MUSCULATURE IN HEALTH ANDDISEASE

Because no detailed information exists regarding the topographic repre sentation of swallowing musculature on the human cerebral cortex in he alth or disease, we used transcranial magnetic stimulation to study th e cortical topography of human oral, pharyngeal and esophageal muscula ture in 20 healthy individuals and the topography of pharyngeal muscul ature in two stroke patients, one with and one without dysphagia. Our results demonstrate that swallowing musculature is discretely and soma totopically represented on the motor and premotor cortex of both hemis pheres but displays interhemispheric asymmetry, independent of handedn ess. Following stroke, dysphagia appeared to be associated with smalle r pharyngeal representation on the intact hemisphere, which increases in size with recovery of swallowing.