Vestibular nerve
Encyclopedia
The vestibular nerve is one of the two branches of the Vestibulocochlear nerve
Vestibulocochlear nerve
The vestibulocochlear nerve is the eighth of twelve cranial nerves, and is responsible for transmitting sound and equilibrium information from the inner ear to the brain...

 (the cochlear nerve
Cochlear nerve
The cochlear nerve is a nerve in the head that carries signals from the cochlea of the inner ear to the brain...

 being the other). It goes to the semicircular canals via the vestibular ganglion. It receives positional information.

Axons of the vestibular nerve synapse in the vestibular nucleus on the lateral floor and wall of the fourth ventricle
Fourth ventricle
The fourth ventricle is one of the four connected fluid-filled cavities within the human brain. These cavities, known collectively as the ventricular system, consist of the left and right lateral ventricles, the third ventricle, and the fourth ventricle...

 in the pons
Pons
The pons is a structure located on the brain stem, named after the Latin word for "bridge" or the 16th-century Italian anatomist and surgeon Costanzo Varolio . It is superior to the medulla oblongata, inferior to the midbrain, and ventral to the cerebellum. In humans and other bipeds this means it...

 and medulla
Medulla oblongata
The medulla oblongata is the lower half of the brainstem. In discussions of neurology and similar contexts where no ambiguity will result, it is often referred to as simply the medulla...

.

It arises from bipolar cells in the vestibular ganglion, ganglion of Scarpa, which is situated in the upper part of the outer end of the internal auditory meatus
Internal auditory meatus
The internal auditory meatus is a canal in the petrous part of the temporal bone of the skull that carries nerves from inside the cranium towards the middle and inner ear compartments namely cranial nerve VII and cranial nerve VIII.-Structure:The...

.

Branches

The peripheral fibers divide into three branches (some sources list two):
  • the superior branch passes through the foramina in the area vestibularis superior and ends in the utricle and in the ampullae of the superior and lateral semicircular ducts;
  • the fibers of the inferior branch traverse the foramina in the area vestibularis inferior and end in the saccule
    Saccule
    The saccule is a bed of sensory cells situated in the inner ear. The saccule translates head movements into neural impulses which the brain can interpret. The saccule is sensitive to linear translations of the head, specifically movements up and down...

    ;
  • the posterior branch runs through the foramen singulare
    Foramen singulare
    In the temporal bone, in the portion beneath the crista falciformis are three sets of foramina; one group, just below the posterior part of the crest, situated in the area cribrosa media, consists of several small openings for the nerves to the saccule; below and behind this area is the foramen...

     and supplies the ampulla of the posterior semicircular duct.

External links

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