The glossopharyngeal nerve participates in the innervation of structures in the glossus (tongue) and the pharynx, as well as the middle ear, and parasympathetic innervation.
Course
- The glossopharyngeal nerve leaves the cranium through the anterior jugular foramen.
- It gives off the tympanic branch:
- Also known as Jacobson's nerve, which has both sensory and parasympathetic fibers.
- It passes through the petrous part of the temporal bone via the tympanic canaliculus, forming the tympanic plexus and then becomes the lesser petrosal nerve
- The lesser petrosal nerve leaves the cranium through foramen ovale and provides presynaptic parasympathetic fibers to the otic