The facial nerve provides motor innervation to all the muscles of facial expression and the 3 muscle derivatives of the second pharyngeal arch (posterior digastric, stapedius, and stylohyoid). It parasympathetically fires 3 of the 4 glands in the head: the submandibular and sublingual salivary glands and the lacrimal gland (A). Other parasympathetic fibers stimulate mucous secretion in the nose and palate. Taste fibers from the anterior two-thirds of the tongue follow the path of the lingual branch of cranial nerve (CN) VII until just before entering the cranium as a distinct chorda tympani nerve (B).
