NETTER - Neuroscience Flash Cards

Vestibulocochlear Nerve (CN VIII)
1. Vestibulocochlear nerve
(CN VIII)
2. Cochlear part of CN VIII
3. Spiral ganglion
4. Geniculate ganglion of CN
VII
5. Ampulla of superior
semicircular duct
6. Ampulla of lateral
semicircular duct
7. Utricle
8. Ampulla of posterior
semicircular duct
9. Saccule
10. Vestibular ganglion
(Scarpa’s ganglion)
11. Vestibular part of CN VIII
12. Internal acoustic meatus
13. Cochlear nuclei
14. Inferior cerebellar peduncle
15. Vestibular nuclei
Comment: Vestibular division of CN VIII arises from bipolar primary
sensory neurons in the vestibular (Scarpa’s) ganglion. The peripheral
process innervates hair cells in the utricle and saccule that respond
to linear acceleration (gravity) and in the ampullae of the semicircular
ducts that respond to angular acceleration (movement); the central
process of ganglion cells terminates in the vestibular nuclei and
vestibular portion of the cerebellum. Vestibular nerve irritation (e.g.,
acoustic schwannoma) can result in vertigo, dizziness, nausea, and
unsteadiness of spatial disorientation. These symptoms persist with
nerve destruction. Auditory division of CN VIII arises from bipolar
primary sensory neurons in spiral ganglion. The peripheral process
innervates hair cells that lie along the organ of Corti on the basilar
membrane in the cochlear duct. The central process of ganglion
cells conveys hearing information to the cochlear nuclei. Auditory
nerve irritation may first produce tinnitus (ringing, roaring), followed
by slow loss of hearing and inability to determine the direction from
which a sound is coming. Destruction of the auditory nerve results in
profound ipsilateral deafness.
Regional Neuroscience See book 11.25