- Vestibulocochlear nerve
Nerve: Vestibulocochlear nerve The course and connections of the facial nerve in the temporal bone Inferior view of the human brain, with the cranial nerves labelled. Gray's subject #203 To cochlear nerve, vestibular nerve MeSH Vestibulocochlear+Nerve Cranial Nerves CN I – Olfactory CN II – Optic CN III – Oculomotor CN IV – Trochlear CN V – Trigeminal CN VI – Abducens CN VII – Facial CN VIII – Vestibulocochlear CN IX – Glossopharyngeal CN X – Vagus CN XI – Spinal Accessory CN XII – Hypoglossal
The vestibulocochlear nerve (also known as the auditory or acoustic nerve) is the eighth of twelve cranial nerves, and is responsible for transmitting sound and equilibrium (balance) information from the inner ear to the brain. The acoustic nerve is derived from the embryonic otic placode.
Structure and function
This is the nerve along which the sensory cells (the hair cells) of the inner ear transmit information to the brain. It consists of the cochlear nerve, carrying information about hearing, and the vestibular nerve, carrying information about balance. It emerges from the pons and exits the inner skull via the internal acoustic meatus (or internal auditory meatus) in the temporal bone.
The cochlear nerve travels away from the cochlea of the inner ear where it starts as the spiral ganglia. Processes from the organ of Corti conduct afferent transmission to the spiral ganglia. It is the inner hair cells of the organ of Corti that are responsible for activation of afferent receptors in response to pressure waves reaching the basilar membrane through the transduction of sound. The exact mechanism by which sound is transmitted by the neurons of the cochlear nerve is uncertain; the two competing theories are place theory and temporal theory.
The vestibular nerve travels from the vestibular system of the inner ear. The vestibular ganglion houses the cell bodies of the bipolar neurons and extends processes to five sensory organs. Three of these are the cristae located in the ampullae of the semicircular canals. Hair cells of the cristae activate afferent receptors in response to rotational acceleration. The other two sensory organs supplied by the vestibular neurons are the maculae of the saccule and utricle. Hair cells of the maculae activate afferent receptors in response to linear acceleration.
Symptoms of damage
Damage to the vestibulocochlear nerve may cause the following symptoms:
- hearing loss
- false sense of motion
- loss of equilibrium (in dark places)
- motion sickness
- gaze-evoked tinnitus.
Some older texts call the nerve the acoustic or auditory nerve , but these terms have fallen out of widespread use because they fail to recognize the nerve's role in the vestibular system. Vestibulocochlear nerve is therefore preferred by most.
- ^ Coad, ML; Lockwood, A; Salvi, R; Burkard, R (2001). "Characteristics of patients with gaze-evoked tinnitus". Otology & neurotology : official publication of the American Otological Society, American Neurotology Society [and] European Academy of Otology and Neurotology 22 (5): 650–4. PMID 11568674.
- MedEd at Loyola GrossAnatomy/h_n/cn/cn1/cn8.htm
- cranialnerves at The Anatomy Lesson by Wesley Norman (Georgetown University) (VIII)
Nerves of head and neck: the cranial nerves and nuclei (TA A14.2.01, GA 9.855) olfactory (AON->I) optic (LGN->II) oculomotor
trochlear (TN->IV)no significant branches trigeminal
(PSN, TSN, MN, TMN->V)
abducens (AN->VI)no significant branches facial (FMN, SN, SSN->VII)near origininside
(NA, ISN, SN->IX)before jugular fossaafter jugular fossa
(NA, DNVN, SN->X)before jugular fossaafter jugular fossa
accessory (NA, SAN->XI) hypoglossal (HN->XII) Auditory and vestibular pathways Auditory VestibularVestibulo-oculomotor fibers
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Vestibulocochlear nerve — A nerve that is responsible for the sense of hearing and which is also pertinent to balance, to the body position sense. Problems with the vestibulocochlear nerve may result in deafness, tinnitus (ringing or noise in the ears), dizziness, vertigo … Medical dictionary
vestibulocochlear nerve — ▪ anatomy also called Auditory Nerve, Acoustic Nerve, or Eighth Cranial Nerve, nerve in the human ear, serving the organs of equilibrium and of hearing. It consists of two anatomically and functionally distinct parts: the cochlear nerve … Universalium
vestibulocochlear nerve — noun a composite sensory nerve supplying the hair cells of the vestibular organ and the hair cells of the cochlea • Syn: ↑acoustic nerve, ↑auditory nerve, ↑nervus vestibulocochlearis, ↑eighth cranial nerve • Hypernyms: ↑cranial nerve • … Useful english dictionary
vestibulocochlear nerve — the eighth cranial nerve (VIII), responsible for carrying sensory impulses from the inner ear to the brain. It has two branches, the vestibular nerve and the cochlear nerve … The new mediacal dictionary
vestibulocochlear nerve — noun Date: 1962 auditory nerve … New Collegiate Dictionary
Нерв Преддверно-Улитковый (Vestibulocochlear Nerve, Acoustic Nerve), Нерв Слуховой (Auditory Nerve) — восьмой черепно мозговой чувствительный нерв (VIII), по которому от внутреннего уха к головному мозгу поступают импульсы от вестибулярного аппарата и кортиева органа внутреннего уха. Этот нерв имеет две части: нерв преддверия (vestibular nerve) и … Медицинские термины
cochlear root of vestibulocochlear nerve — radix cochlearis nervi vestibulocochlearis … Medical dictionary
inferior root of vestibulocochlear nerve — radix cochlearis nervi vestibulocochlearis … Medical dictionary
superior root of vestibulocochlear nerve — radix vestibularis nervi vestibulocochlearis … Medical dictionary
vestibular root of vestibulocochlear nerve — radix vestibularis nervi vestibulocochlearis … Medical dictionary