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Information about Hypoglossal Nerve

Nerve: Hypoglossal nerve
Hypoglossal nerve, cervical plexus, and their branches.
Latinnervus hypoglossus
subject #207 914
Innervatesgenioglossus, hyoglossus, styloglossus
Toansa cervicalis
MeSH Hypoglossal+Nerve
The hypoglossal nerve is the twelfth cranial nerve (XII). The nerve arises from the hypoglossal nucleus and emerges from the medulla oblongata in the preolivary sulcus separating the olive and the pyramid. It then passes through the hypoglossal canal. On emerging from the hypoglossal canal, the nerve picks up a branch from the anterior ramus of C1. It spirals behind the vagus nerve and passes between the internal carotid artery and internal jugular vein lying on the carotid sheath. After passing deep to the posterior belly of the digastric muscle, it passes to the submandibular region to enter the tongue.

It supplies motor fibres to all of the muscles of the tongue, except the palatoglossus muscle which is innervated by the vagus nerve (X).

Testing the hypoglossal nerve

To test the function of the nerve, a person is asked to poke out their tongue. If there is a loss of function on one side (unilateral paralysis) the tongue will point towards the affected side.

The strength of the tongue can be tested by getting the person to poke the inside of their cheek, and feeling how strongly they can push a finger pushed against their cheek - a more elegant way of testing than directly touching the tongue.

The tongue can also be looked at for signs of lower motor neuron disease, such as fasciculation and atrophy.

Additional images


Veins of the tongue. The hypoglossal nerve has been displaced downward in this preparation.

Section of the medulla oblongata at about the middle of the olive.

Diagram showing the course of the arcuate fibers.

Transverse section passing through the sensory decussation.

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

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

Plan of hypoglossal nerve.

The mouth cavity.


External links

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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 cervical plexus is a plexus of the ventral rami of the first four cervical spinal nerves which are located from C1 to C4 cervical segment in the neck. They are located laterally to the transverse processes between prevertebral muscles from the medial side and vertebral (m.
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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 genioglossus is a muscle of the human body which runs from the chin to the tongue.

Structure

Genioglossus is the fan-shaped extrinsic tongue muscle that forms the majority of the body of the tongue.
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The Hyoglossus, thin and quadrilateral, arises from the side of the body and from the whole length of the greater cornu of the hyoid bone, and passes almost vertically upward to enter the side of the tongue, between the Styloglossus and Longitudinalis inferior.
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The Styloglossus, the shortest and smallest of the three styloid muscles, arises from the anterior and lateral surfaces of the styloid process, near its apex, and from the stylomandibular ligament.
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The ansa cervicalis (or ansa hypoglossi in older literature) is a loop of nerves that are part of the cervical plexus.

Branches from the ansa cervicalis innervate the infrahyoid muscles except the thyrohyoid muscle: the sternohyoid muscle, the sternothyroid muscle,
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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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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 hypoglossal nucleus is a cranial nerve nucleus, and it extends the length of the medulla, and being a motor nucleus, is close to the midline. In the open medulla, it is visible as what is known as the hypoglossal trigone
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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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Sulcus (pl. sulci) is a Latin word :
  • used in Latin to refer to a groove, furrow or trench.
  • used in planetary geology to refer to subparallel grooves and ditches formed by geological processes.

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The hypoglossal canal is a bony canal in the occipital bone of the skull that transmits the hypoglossal nerve from its point of entry near the medulla oblongata to its exit from the base of the skull near the jugular foramen.
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Anterior can refer to:
  • Anterior and posterior, both Anatomical terms of location
  • Anterior (band), A Welsh Metal band

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Ramus can refer to:
  • Petrus Ramus
  • A portion of a bone (from Latin ramus, "branch"), as in the Ramus mandibulæ or Superior pubic ramus
  • A nerve ramus such as the Dorsal ramus of spinal nerve

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In vertebrates, cervical vertebrae (singular: vertebra) are those vertebrae immediately behind (caudal to) the skull.

Variation among species

In some species, some parts of the skull may be composed of vertebra-like elements, e.g.
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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 human anatomy, the internal carotid artery is a major artery of the head and neck that helps supply blood to the brain.

Classification

Terminologia Anatomica currently breaks the artery into four parts: "cervical", "petrous", "cavernous", and "cerebral".
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The internal jugular vein collects the blood from the brain, from the superficial parts of the face, and from the neck.

Path

It is directly continuous with the sigmoid sinus, and begins in the posterior compartment of the jugular foramen, at the base of the skull.
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The carotid sheath is an anatomical term for the fibrous connective tissue that surrounds the internal carotid artery and related structures in the neck.

Structure


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The digastric muscle (named digastric as it has two bellies) is a small muscle located under the jaw.

It lies below the body of the mandible, and extends, in a curved form, from the mastoid process to the symphysis menti. It belongs to the suprahyoid muscles group.
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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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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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The palatoglossus (glossopalatinus) is a small fleshy fasciculus, narrower in the middle than at either end, forming, with the mucous membrane covering its surface, the glossopalatine arch.
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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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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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Lower motor neurons (LMNs) are the motor neurons connecting the brainstem and spinal cord to muscle fibers, bringing the nerve impulses from the upper motor neurons out to the muscles.
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MeSH D005207 A fasciculation (or "muscle twitch") is a small, local, involuntary muscle contraction (twitching) visible under the skin arising from the spontaneous discharge of a bundle of skeletal muscle fibers.
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For the American thrash metal band, see Atrophy (band)
Atrophy is the partial or complete wasting away of a part of the body. Causes of atrophy include poor nourishment, poor circulation, loss of hormonal support, loss of nerve supply to the target organ,
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NeuroNames is a system of nomenclature for the human and/or macaque brain.

It is maintained by the University of Washington and is a part of a tool called "BrainInfo". BrainInfo helps one identify structures in the brain.
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Loyola University Chicago is a private co-educational religious-affiliated university established in Chicago in 1870 as Saint Ignatius College. It was founded by the Roman Catholic religious order of the Society of Jesus and bears the name of the Jesuit patron, Saint Ignatius of
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