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Flashcards in CN VIII Deck (52)
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1

What is the name given to CN VIII?

Vestibulocochlear nerve

2

What kind of information is carried by CN VII?

special sensory only

3

How many nerves make up CN VIII and what are they?

2; vestibular and cochlear

4

Where does the vestibular nerve terminate?

vestibular nuclear complex

5

What are the 4 parts of the vestibular nuclear complex?

superior (bechterew), medial (schwalbe), lateral (deiter), and inferior

6

Which part of the vestibular nuclear complex gives rise to most of the fibers of the vestibulospinal tract?

lateral (deiter)

7

Where do fibers in the vestibular nerve originate?

cell bodies in the vestibular ganglion

8

Where is the vestibular ganglion?

internal acoustic meatus

9

T/F: the vestibular ganglion has 2 parts, inferior and superior.

true

10

Where does the cochlear nerve terminate?

in the two cochlear nuclei (anterior and posterior)

11

Where do the axons composing the cochlear nerve originate?

spinal ganglion

12

What kind of neurons make up the cochlear nerve?

bipolar neurons

13

Where are the cell bodies of the neurons that make up the cochlear nerve?

in the spiral ganglion of the cochlea

14

What is the route of peripheral processes of the cochlear nerve?

from spiral ganglion to spiral organ

15

What is the other name for the spiral organ?

organ of Corti

16

Where are the nuclei of termination for the cochlear nerve (cochlear nuclei) located?

in the posterior, superior MO, lateral to the vestibular nuclei

17

From the cochlear nuclei, axons cross to the other side of the brainstem and synapse in what nuclei?

trapezoid nuclei

18

What do axons from the trapezoid nucleus form?

lateral lemniscus

19

Where do fibers from the lateral lemniscus travel?

to medial geniculate body of thalamus (with a few fibers dropping off in the inferior colliculus)

20

What 3 inner ear structures are innervated by peripheral processes from the vestibular ganglion?

saccule, utricle, and semicircular canals

21

Where are the vestibular nuclei?

in the MO on the floor of the rhomboid fossa

22

Where do central processes from the vestibular ganglion convey info to?

vestibular nuclei

23

Where do most vestibular nerve fibers terminate?

in the medial vestibular nucleus (Schwalbe)

24

How do some fibers of the vestibular nerve travel directly to the cerebellum?

by way of the inferior cerebellar peduncle

25

Which direction does info in CN VIII travel?

from distal to proximal

26

Where is the apparent origin of CN VIII?

cerebellopontine angle

27

T/F: CN VIII has no branches to structures outside of the ear.

True

28

From its apparent origin, what fossa does CN VIII travel in to get to the internal acoustic meatus?

posterior cranial fossa

29

What other cranial nerve enters the internal acoustic meatus along with CN VIII

Facial (VII)

30

T/F: The cochlear nerve carries about 60,000 fibers.

False; 30-40k