Glossopharyngeal nerve or cranial nerve IX

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Description:

The glossopharyngeal nerve is a mixed nerve. Sensory axons of the glossopharyngeal nerve arise from taste buds and somatic sensory receptors on the posterior one-third of the tongue, form proprioceptors in swallowing muscles supplied by the motor portion, from baroreceptors (stretch receptors) in the carotid sinus, and from chemoreceptors in the carotid body. The cell bodies of these sensory neurons reside in the superior and inferior ganglia of the nerve and the sensory axons then pass from the ganglia through the jugular foramen to end in the medulla oblongata.
Axons of motor neurons in the glossopharyngeal nerve arise in nuclei of the medulla and exit the skull through the jugular foramen. Branchial motor neurons innervate the stylopharyngeus muscle, and parasympathetic motor neurons stimulate the parotid gland after synapsing within the otic ganglion.