The pharyngeal plexus occurs upon the outer surface of the
pharynx - especially superficial to the
middle pharyngeal constrictor muscle. •
Motor –
pharyngeal branch of vagus nerve (CN X) which arises from the superior portion of the
inferior ganglion of vagus nerve, with the neuron cell bodies of its axons residing in the
nucleus ambiguus. The pharyngeal branch ramifies upon reaching the superior border of the middle pharyngeal constrictor muscle. It is unclear whether the
cranial root of accessory nerve (CN XI) This includes an outer circular layer of
three constrictor muscles (superior, middle, inferior) that propel food downwards and an inner longitudinal layer (
stylopharyngeus,
salpingopharyngeus,
palatopharyngeus) that elevate the larynx and shorten the pharynx during swallowing.
Sensory The pharyngeal plexus provides sensory innervation to most of the pharynx; it provides sensory innervation to the
oropharynx and
laryngopharynx from CN IX and CN X. (The
nasopharynx above the pharyngotympanic tube and the
torus tubarius is innervated by
CN V2). ==See also==