Glossopharyngeal nerve

GLOSSOPHARYNGEAL NERVE ANATOMY

The glossopharyngeal nerve is responsible for the innervation of part of the tongue and the pharynx. This mixed nerve finds its roots of its motor fibers in the nucleus within the medulla oblongata.

These fibers then exit through the jugular foramen. Theses motor fibers are on their way to innervate the pharynx muscles as well as the parotid gland.

GLOSSOPHARYNGEAL NERVE STRUCTURE

The parotid gland relies on this innervation for stimulation that kicks in the reflex of swallowing. It also stimulates saliva secretions.

The parotid gland, the posterior one third of the taste buds, the middle ear cavity, and the rest of the pharyngeal area are the beginning source of the sensory fibers for the glosspharyngeal nerve. The taste buds served by this nerve also serve as chemoreceptors.

The carotid sinuses within the neck are in part responsible for some of the sensory fibers related to the glossopharyngeal nerve. These fibers are designed to help provide specific regulations as they relate to blood pressure.

GLOSSOPHARYNGEAL NERVE DIAGRAM

GLOSSOPHARYNGEAL NERVE FUNCTIONS

The glossopharyngeal nerve is the conduit for impulses that run through the medulla oblongata, to synapse in thalamus, and travel along the fibers which take the impulses to the area of the gustatory reception in the cerebral cortex.

If damage occurs to the motor nerve, the patient would have significant difficulty swallowing. If the sensory portion of the glossopharyngeal nerve becomes damaged, tastes such as bitterness, sourness, and tastes along the posterior region become muted or absent.