anatomy of the parasympathetic component
Last reviewed 01/2018
The parasympathetic division of the glossopharyngeal nerve begins at the inferior salivatory nucleus in the upper medulla. The nucleus receives input from the hypothalamus and the reticular formation.
Preganglionic nerve fibres leave this site and pass via the jugular foramen with the motor component of IX. The fibres then pass into the middle ear through a fissure in the temporal bone, join a tympanic plexus of sensory fibres, and then pass on with a branch of the facial nerve as the lesser petrosal nerve. The lesser petrosal nerve exits the skull via the foramen ovale before descending into the infratemporal fossa and then synapsing with the otic ganglion.
The postganglionic fibres from the otic ganglion innervate the parotid gland.