Glossopharyngeal nerve is a mixed cranial nerve that contains parasympathetic fibers, which innervate the carotid sinus/body, which if massaged will decrease the heart rate. Additionally, it provides special sense (taste) to the posterior third of the tongue (bitter area) as well as innervating the parotid glands, which helps with salivation. It also functions as the afferent/sensory arm of the gag reflex.