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Information about Cn Ix

Nerve: Glossopharyngeal nerve
Plan of upper portions of glossopharyngeal, vagus, and accessory nerves.
Course and distribution of the glossopharyngeal, vagus, and accessory nerves. (Label for glossopharyngeal is at upper right.)
Latinnervus glossopharyngeus
subject #204 906
Innervatesstylopharyngeus
Totympanic nerve
MeSH Glossopharyngeal+Nerve
Dorlands/Elsevier n_05/12565844
The glossopharyngeal nerve is the ninth of twelve pairs of cranial nerves. It exits the brainstem out from the sides of the upper medulla, just rostral (closer to the nose) to the vagus nerve.

Functions

There are a number of functions of the glossopharyngeal nerve:

Brainstem connections

The glossopharyngeal nerve, being mostly sensory, does not have a cranial nerve nucleus of its own. Instead it must project into many different structures in the brainstem:

Path

From the medulla oblongata, the glossopharyngeal nerve passes laterally across the flocculus, and leaves the skull through the central part of the jugular foramen, in a separate sheath of the dura mater, lateral to and in front of the vagus and accessory nerves. Within the jugular foramen, the glossopharyngeal nerve forms the superior ganglion (the glossopharyngeal neve is also associated with an inferior ganglion).

In its passage through the jugular foramen, it grooves the lower border of the petrous part of the temporal bone; and, at its exit from the skull, passes forward between the internal jugular vein and internal carotid artery. It descends in front of the latter vessel, and beneath the styloid process and the muscles connected with it, to the lower border of the stylopharyngeus. It then curves forward, forming an arch on the side of the neck and lying upon the stylopharyngeus and middle pharyngeal constrictor muscle. From there it passes under cover of the hyoglossus muscle, and is finally distributed to the palatine tonsil, the mucous membrane of the fauces and base of the tongue, and the mucous glands of the mouth.

Branches

1. Tympanic
2. Stylopharyngeal
3. Tonsillar
4. Nerve to carotid sinus
5. Branches to the posterior third of tongue

Note: The glossopharyneal nerve contributes in the formation of the pharyngeal plexus along with the vagus nerve.

Testing the glossopharyngeal nerve

The gag reflex is absent in patients with damage to the glossopharyngeal nerve as it is responsible for the afferent limb of the reflex.

Additional images


Dura mater and its processes exposed by removing part of the right half of the skull, and the brain.

Hind- and mid-brains; postero-lateral view.

Alveolar branches of superior maxillary nerve and sphenopalatine ganglion.

Upper part of medulla spinalis and hind- and mid-brains; posterior aspect, exposed in situ.

Hypoglossal nerve, cervical plexus, and their branches.


External links

 •  • [ e]
Nerves of head and neck: the cranial nerves
I-IVolfactory • optic • oculomotor (superior branch, inferior branch) • trochlear
V: trigeminaltrigeminal ganglion • ophthalmic • maxillary • mandibular
VI: abducensno significant branches
VII: facialnervus intermedius • geniculate • inside facial canal (greater petrosal, nerve to the stapedius, chorda tympani) • at exit from stylomastoid foramen (posterior auricular, digastric • stylohyoid) • on face (temporal, zygomatic, buccal, mandibular, cervical)
VIII: vestibulocochlearcochlear (striae medullares, lateral lemniscus) • vestibular (Scarpa's ganglion)
IX: glossopharyngealnucleus ambiguus • ganglia (superior, petrous) • tympanic (tympanic plexus, lesser petrosal) • carotid sinus • pharyngeal branches • pharyngeal plexus
X: vagusganglia (jugular, nodose) • Alderman's nerve • in the neck (pharyngeal branch, superior laryngeal ext and int, recurrent laryngeal) • in the thorax (pulmonary branches, esophageal plexus) • in the abdomen (gastric plexuses, celiac plexus, gastric plexus)
XI-XIIaccessory • hypoglossal
The glossopharyngeal nerve is the ninth of twelve pairs of cranial nerves. It exits the brainstem out from the sides of the upper medulla, just rostral (closer to the nose) to the vagus nerve.
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The vagus nerve (also called pneumogastric nerve or cranial nerve X) is the tenth of twelve paired cranial nerves, and is the only nerve that starts in the brainstem (within the medulla oblongata) and extends, through the jugular foramen, down below the head, to the
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In anatomy, the accessory nerve is a nerve that controls specific muscles of the neck. As a part of it is traditionally believed to originate in the brain, it is considered a cranial nerve.
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The glossopharyngeal nerve is the ninth of twelve pairs of cranial nerves. It exits the brainstem out from the sides of the upper medulla, just rostral (closer to the nose) to the vagus nerve.
..... Click the link for more information.
The vagus nerve (also called pneumogastric nerve or cranial nerve X) is the tenth of twelve paired cranial nerves, and is the only nerve that starts in the brainstem (within the medulla oblongata) and extends, through the jugular foramen, down below the head, to the
..... Click the link for more information.
In anatomy, the accessory nerve is a nerve that controls specific muscles of the neck. As a part of it is traditionally believed to originate in the brain, it is considered a cranial nerve.
..... Click the link for more information.
Latin}}} 
Official status
Official language of: Vatican City
Used for official purposes, but not spoken in everyday speech
Regulated by: Opus Fundatum Latinitas
Roman Catholic Church
Language codes
ISO 639-1: la
ISO 639-2: lat
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The stylopharyngeus is a muscle in the head that stretches between the styloid process and the pharynx.

Structure

The stylopharyngeus is a long, slender muscle, cylindrical above, flattened below.
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The tympanic nerve (nerve of Jacobson) arises from the petrous ganglion, and ascends to the tympanic cavity through a small canal on the under surface of the petrous portion of the temporal bone on the ridge which separates the carotid canal from the jugular fossa.
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Medical Subject Headings (MeSH) is a huge controlled vocabulary (or metadata system) for the purpose of indexing journal articles and books in the life sciences. Created and updated by the United States National Library of Medicine (NLM), it is used by the MEDLINE/PubMed
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Elsevier, the world's largest publisher of medical and scientific literature, forms part of the Reed Elsevier group. Based in Amsterdam, the company has substantial operations in the UK, USA and elsewhere.
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Cranial nerves are nerves that emerge directly from the brain in contrast to spinal nerves which emerge from segments of the spinal cord. Although thirteen cranial nerves in humans fit this description, twelve are conventionally recognized.
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The medulla oblongata is the lower portion of the brainstem.

Location

By anatomical terms of location, it is rostral to the spinal cord and caudal to the pons, which is in turn ventral to the cerebellum.
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The vagus nerve (also called pneumogastric nerve or cranial nerve X) is the tenth of twelve paired cranial nerves, and is the only nerve that starts in the brainstem (within the medulla oblongata) and extends, through the jugular foramen, down below the head, to the
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Sensory neurons (neurones) are nerve cells within the nervous system responsible for converting external stimuli from the organism's environment into internal electrical motor reflex loops and several forms of involuntary behavior, including pain avoidance.
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The tongue is the large bundle of skeletal muscles on the floor of the mouth that manipulates food for chewing and swallowing (deglutition). It is the primary organ of taste. Much of the surface of the tongue is covered in taste buds.
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For the structure in the cerebellum, see cerebellar tonsil.
The tonsils are areas of lymphoid tissue on either side of the throat. An infection of the tonsils is called tonsillitis.
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The pharynx (plural: pharynges) is the part of the neck and throat situated immediately posterior to the mouth and nasal cavity, and cranial, or superior, to the esophagus, larynx, and trachea.
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The middle ear is the portion of the ear internal to the eardrum, and external to the oval window of the cochlea. The mammalian middle ear contains three ossicles, which couple vibration of the eardrum into waves in the fluid and membranes of the inner ear.
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The carotid body (or carotid glomus) is a small cluster of chemoreceptors and supporting cells located near the bifurcation of the carotid artery.

It measures changes in the composition of arterial blood flowing through it, mainly the partial pressure of oxygen, but
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parasympathetic nervous system (PSNS) is one of three divisions of the autonomic nervous system (ANS). The ANS -a subdivision of the peripheral nervous system (PNS)- is subdivided into the sympathetic (SNS), parasympathetic (PSNS) and enteric (bowels) nervous system (ENS).
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For the toad wart, see parotoid gland.

The parotid gland is the largest of the salivary glands. It is found wrapped around the mandibular ramus, and it secretes saliva through Stensen's duct into the oral cavity, to facilitate mastication and swallowing.
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The otic ganglion is a small, ovalshaped, flattened parasympathetic ganglion of a reddish-gray color, located immediately below the foramen ovale.

Location and relations


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Motor nerves allow the brain to stimulate muscle contraction. A motor nerve is an efferent nerve that exclusively contains the axons of somatic and branchial motoneurons, which innervate skeletal muscles (that ensure locomotion) and branchial muscles (that motorize the face and
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The stylopharyngeus is a muscle in the head that stretches between the styloid process and the pharynx.

Structure

The stylopharyngeus is a long, slender muscle, cylindrical above, flattened below.
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The pharyngeal plexus is a network of nerve fibers supplied by the pharyngeal branch of vagus nerve joining with branches from the pharyngeal branches of glossopharyngeal nerve, sympathetic fibers, and the external laryngeal nerve.
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A cranial nerve nucleus is a collection of neurons (gray matter) in the brain stem that is associated with one or more cranial nerves. Axons carrying information to and from the cranial nerves form a synapse first at these nuclei.
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The solitary nucleus and tract are structures in the brainstem that carry and receive visceral sensation and taste from the facial (VII), glossopharyngeal (IX), vagus (X) cranial nerves, as well as the cranial part of the accessory nerve (XI).
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Baroreceptors (or baroceptors) in the human body detect the pressure of blood flowing through them, and can send messages to the central nervous system to increase or decrease total peripheral resistance and cardiac output.
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A chemosensor, also known as chemoreceptor, is a cell or group of cells that transduce a chemical signal into an action potential. Or, more generally, a chemosensor detects certain chemical stimuli in the environment.
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