When a large bolus of food is swallowed, the hyoid bone moves anteriorly to open the pharynx. The muscle responsible for this action is innervated by which of the following nerves?
The muscle that moves the hyoid anteriorly to open the pharynx is the geniohyoid. This muscle is innervated by the ansa cervicalis branch of C1. The ansa cervicalis also innervates the thyrohyoid and the intra hyoids. Note: Cranial nerve IX innervates the stylopharyngeus. The pharyngeal plexus innervates the palatoglossus, palatopharyngeus, and cricopharyngeus. Cranial nerve V-3 innervates most of the muscles of mastication.
C1 (ansa cervicalis)
CN IX
Pharyngeal plexus
CN V3