The inferior ganglion of the

glossopharyngeal nerve The glossopharyngeal nerve (), also known as the ninth cranial nerve, cranial nerve IX, or simply CN IX, is a cranial nerve that exits the brainstem from the sides of the upper medulla, just anterior (closer to the nose) to the vagus nerve. ...

(petrosal ganglion) is a sensory ganglion. It is larger than and inferior to the superior ganglion of the glossopharyngeal nerve. It is located within the

jugular foramen A jugular foramen is one of the two (left and right) large foramina (openings) in the base of the skull, located behind the carotid canal. It is formed by the temporal bone and the occipital bone. It allows many structures to pass, including the ...

. The pseudounipolar neurons of the inferior ganglion of the glossopharyngeal nerve provide sensory innervation to areas around the tongue and pharynx. More specifically: # innervation of

taste bud Taste buds contain the taste receptor cells, which are also known as gustatory cells. The taste receptors are located around the small structures known as papillae found on the upper surface of the tongue, soft palate, upper esophagus, the c ...

s on the posterior 1/3 of tongue # general sensory innervation of posterior 1/3 of tongue,

soft palate The soft palate (also known as the velum, palatal velum, or muscular palate) is, in mammals, the soft tissue constituting the back of the roof of the mouth. The soft palate is part of the palate of the mouth; the other part is the hard palate. ...

palatine tonsil Palatine tonsils, commonly called the tonsils and occasionally called the faucial tonsils, are tonsils located on the left and right sides at the back of the throat, which can often be seen as flesh-colored, pinkish lumps. Tonsils only present a ...

s, upper pharynx and Eustachian tubes # innervation of baroreceptor cells in the carotid sinus # innervation of glomus type I chemoreceptor cells in the

carotid body The carotid body is a small cluster of chemoreceptor cells, and supporting sustentacular cells. The carotid body is located in the adventitia, in the bifurcation (fork) of the common carotid artery, which runs along both sides of the neck. The ...

The central processes of the neurons which provide taste sensation synapse in the rostral portion of the

solitary nucleus In the human brainstem, the solitary nucleus, also called nucleus of the solitary tract, nucleus solitarius, and nucleus tractus solitarii, (SN or NTS) is a series of purely sensory nuclei (clusters of nerve cell bodies) forming a vertical column ...

(also called the gustatory nucleus). The central processes of the neurons which provide general sensory information synapse in the

spinal trigeminal nucleus The spinal trigeminal nucleus is a nucleus in the medulla that receives information about deep/crude touch, pain, and temperature from the ipsilateral face. In addition to the trigeminal nerve (CN V), the facial (CN VII), glossopharyngeal (CN IX), ...

. Finally, the central processes of the neurons which innervate the carotid sinus and carotid body synapse in the caudal portion of the solitary nucleus.

Tympanic nerve

The

tympanic nerve The tympanic nerve (Jacobson’s nerve) is a branch of the glossopharyngeal nerve found near the ear. It gives sensation to the middle ear, the Eustachian tube, the parotid gland, and Mastoid cells, mastoid air cells. It gives parasympathetic to ...

is the first branch of the glossopharyngeal nerve. It branches at the level of the inferior ganglion. Importantly, the axons which form the tympanic nerve do not synapse in this ganglion or have their cell bodies in it. The neuron cell bodies of the axons which form the tympanic nerve are found in the

inferior salivatory nucleus The salivatory nuclei are the superior salivatory nucleus, and the inferior salivatory nucleus that innervate the salivary glands. They are located in the pontine tegmentum in the brainstem. They both are examples of cranial nerve nuclei. The su ...

and superior ganglion of the glossopharyngeal nerve.

References

{{Authority control Somatic ganglia of the head and neck Glossopharyngeal nerve