Other Nerve Contributions -
Chorda Tympani -
Originates from the Facial Nerve (CN VII), travels through the inner ear,
passing between the malleus and incus,
and exits to the infratemporal fossa via the petrotympanic
fissure. Carries parasympathetic fibers from the superior
salivatory nucleus to the submandibular ganglion. The postganglionic
fibers regulate the submandibular and sublingual salivary gland secretions.
Lesser Petrosal Nerve
- Originates from the inferior salivatory nucleus
and leaves with the Glossopharyngeal Nerve (CN IX). The nerve enters
the middle ear creating the Tympanic Plexus of Jacobson
on the promontory. Upon leaving the ear, it is known as the lesser
petrosal nerve.
Otic ganglion - Found
on the posterior surface of the mandibular branch of CN V (V3), parasympathetic
fibers brought via the lesser petrosal nerve synapse and the postganglionic
fibers travel via the auriculotemporal nerve
to the parotid salivary gland to regulate its secretion.
Submandibular Ganglion
- This ganglion "hangs" from the lingual nerve of V3 and is the site of
parasympathetic nerve synapses, having been carried by chorda tympani.
The postganglionic fibers travel to the submandibular and sublingual salivary
glands. Preganglionic parasympathetic fibers can also synapse at
Langley's Ganglion within the submandibular salivary gland itself.