Location and Size
- The inferior ganglion of the glossopharyngeal nerve is located within the jugular foramen.
- It is larger than the superior ganglion of the glossopharyngeal nerve.
- It is also known as the petrosal ganglion.
- The ganglion is a sensory ganglion.
- It is inferior to the superior ganglion.
Sensory Innervation
- The inferior ganglion provides sensory innervation to areas around the tongue and pharynx.
- It innervates taste buds on the posterior 1/3 of the tongue.
- General sensory innervation is provided to the posterior 1/3 of the tongue, soft palate, palatine tonsils, upper pharynx, and Eustachian tubes.
- It also innervates baroreceptor cells in the carotid sinus.
- Glomus type I chemoreceptor cells in the carotid body are innervated by the ganglion.
Central Processes and Synapses
- The central processes of taste sensation neurons synapse in the rostral portion of the solitary nucleus.
- The central processes of general sensory neurons synapse in the spinal trigeminal nucleus.
- Neurons innervating the carotid sinus and carotid body synapse in the caudal portion of the solitary nucleus.
- Synapses occur in specific nuclei for different sensory functions.
- Central processes transmit sensory information to the respective nuclei.
Tympanic Nerve
- The tympanic nerve is the first branch of the glossopharyngeal nerve.
- It branches at the level of the inferior ganglion.
- The axons forming the tympanic nerve do not synapse in the inferior ganglion.
- Neuron cell bodies of the axons are found in the inferior salivatory nucleus and superior ganglion.
- The tympanic nerve has a separate origin and pathway from the inferior ganglion.
References
- Rubin, Michael. Netter's Concise Neuroanatomy. Philadelphia, PA: Elsevier, 2017.
- Safdieh, Joseph E., Netter, Frank H. (Frank Henry). Updated edition.
- The book provides detailed information on neuroanatomy.
- Page numbers 253-256 cover relevant content.
- ISBN: 9780323480918, OCLC: 946698976.
The inferior ganglion of the glossopharyngeal 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.
| Inferior ganglion of glossopharyngeal nerve | |
|---|---|
 Plan of upper portions of glossopharyngeal, vagus, and accessory nerves. (Inferior ganglion of the glossopharyngeal nerve labeled as ‘petrous gang’. | |
| Details | |
| From | glossopharyngeal nerve |
| Identifiers | |
| Latin | Ganglion inferius nervi glossopharyngei, ganglion petrosum |
| TA98 | A14.2.01.137 |
| TA2 | 6322 |
| FMA | 53475 |
| Anatomical terms of neuroanatomy | |
The pseudounipolar neurons of the inferior ganglion of the glossopharyngeal nerve provide sensory innervation to areas around the tongue and pharynx. More specifically:
The central processes of the neurons which provide taste sensation synapse in the rostral portion of the solitary nucleus (also called the gustatory nucleus). The central processes of the neurons which provide general sensory information synapse in the spinal trigeminal nucleus. Finally, the central processes of the neurons which innervate the carotid sinus and carotid body synapse in the caudal portion of the solitary nucleus.
