The glossopharyngeal nerve serves a function in the pharynx and tongue. The nerve has all sensory, motor and parasympathetic components. It starts in the medulla oblongata and ends in the pharynx. The branchial motor component goes to the stylopharyngeus muscle, the visceral motor controls the smooth muscles of the throat, the visceral sensory component gathers information from the carotid sinus, the general sensory gathers sensory input from the external ear, tympanic membrane, pharynx and tongue and the special sensory component gets taste input from the tongue.