Vestibular nuclei
Encyclopedia
The vestibular nuclei are the cranial nuclei for the vestibular nerve
Vestibular nerve
The vestibular nerve is one of the two branches of the Vestibulocochlear nerve . It goes to the semicircular canals via the vestibular ganglion...

.

In Terminologia Anatomica
Terminologia Anatomica
Terminologia Anatomica is the international standard on human anatomic terminology. It was developed by the Federative Committee on Anatomical Terminology and the International Federation of Associations of Anatomists and was released in 1998. It supersedes the previous standard, Nomina...

 they are grouped in both the pons and medulla.

Subnuclei

There are 4 subnuclei; they are situated at the floor 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...

.
Name Location Notes
medial vestibular nucleus
Medial vestibular nucleus
The medial vestibular nucleus is one of the vestibular nuclei. It is located in the medulla oblongata.Lateral vestibulo-spinal tract - via ventrolateral medulla and spinal cord to ventral funiculus...

 (dorsal or chief vestibular nucleus)
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...

 (floor of 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...

)
corresponding to the lower part of the area acustica in the rhomboid fossa
Rhomboid fossa
The anterior part of the fourth ventricle is named, from its shape, the rhomboid fossa, and its anterior wall, formed by the back of the pons and medulla oblongata, constitutes the floor of the fourth ventricle....

; the caudal end of this nucleus is sometimes termed the descending or spinal vestibular nucleus.
lateral vestibular nucleus
Lateral vestibular nucleus
The lateral vestibular nucleus is the continuation upward and lateralward of the principal nucleus, and in it terminate many of the ascending branches of the vestibular nerve.-Anatomy:...

 or nucleus of Deiters
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...

 (upper)
consisting of large cells and situated in the lateral angle of the rhomboid fossa; the dorso-lateral part of this nucleus is sometimes termed the nucleus of Bechterew.
inferior vestibular nucleus
Inferior vestibular nucleus
The inferior vestibular nucleus is the vestibular nucleus which lies near the fourth ventricle.-External links:* http://www.neuroanatomy.wisc.edu/virtualbrain/BrainStem/13VNAN.html* http://www.anatomyatlases.org/MicroscopicAnatomy/Section17/Plate17331.shtml...

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...

 (lower)
superior vestibular nucleus
Superior vestibular nucleus
The superior vestibular nucleus is the dorso-lateral part of the vestibular nucleus and receives collaterals and terminals from the ascending branches of the vestibular nerve....

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...


Path from medial and lateral nuclei

The fibers of the vestibular nerve enter the medulla oblongata
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...

 on the medial side of those of the cochlear, and pass between the inferior peduncle and the spinal tract of the trigeminal.

They then divide into ascending and descending fibers. The latter end by arborizing around the cells of the medial nucleus, which is situated in the area acustica of the rhomboid fossa
Rhomboid fossa
The anterior part of the fourth ventricle is named, from its shape, the rhomboid fossa, and its anterior wall, formed by the back of the pons and medulla oblongata, constitutes the floor of the fourth ventricle....

. The ascending fibers either end in the same manner or in the lateral nucleus
Lateral nucleus
Lateral nucleus can refer to:* Lateral hypothalamus* Lateral vestibular nucleus...

, which is situated lateral to the area acustica and farther from the ventricular floor.

Some of the axons of the cells of the lateral nucleus
Lateral nucleus
Lateral nucleus can refer to:* Lateral hypothalamus* Lateral vestibular nucleus...

, and possibly also of the medial nucleus, are continued upward through the inferior peduncle to the roof nuclei of the opposite side of the cerebellum
Cerebellum
The cerebellum is a region of the brain that plays an important role in motor control. It may also be involved in some cognitive functions such as attention and language, and in regulating fear and pleasure responses, but its movement-related functions are the most solidly established...

, to which also other fibers of the vestibular root are prolonged without interruption in the nuclei of the medulla oblongata.

A second set of fibres from the medial and lateral nuclei end partly in the tegmentum
Tegmentum
The tegmentum is a general area within the brainstem. It is located between the ventricular system and distinctive basal or ventral structures at each level...

, while the remainder ascend in the medial longitudinal fasciculus to arborize around the cells of the nuclei of the oculomotor nerve
Oculomotor nerve
The oculomotor nerve is the 3rd of 12 paired cranial nerves. It enters the orbit via the superior orbital fissure and controls most of the eye's movements, including constriction of the pupil and maintaining an open eyelid by innervating the Levator palpebrae superiors muscle. The optic nerve is...

.

Fibres from the lateral vestibular nucleus also pass via the vestibulospinal tract
Vestibulospinal tract
The vestibulospinal tract is a component of the extrapyramidal system and also can be classified as a component of the medial pathway. The vestibulospinal fibers relay information from nuclei to motor neurons, like other descending motor pathways. Specifically, the vestibular nuclei receive...

, to anterior horn cells at many levels in the spinal cord, in order to co-ordinate head and trunk movements.

External links

  • http://www.lib.mcg.edu/edu/eshuphysio/program/section8/8ch6/s8ch6_29.htm
  • Parkinson.org
The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
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