Vestibulocochlear Nerve- II Auditory System Flashcards Preview

anatomy block 4 > Vestibulocochlear Nerve- II Auditory System > Flashcards

Flashcards in Vestibulocochlear Nerve- II Auditory System Deck (50):
1

Cochlear Division of CN 8

responds to sounds

2

Vestibular Division of CN 8

Responds to position and movement of the head

3

auricle and external auditory canal

Structure and Function External Ear

A image thumb
4

conducts sound to the tympanic membrane.

ext ear

5

medial boundary of the external ear

tympanic membrane

6

Lateral border of middle ear

tympanic membrane

7

Medial border of middle ear

oval & round windows

petrous part of the temporal bone

8

malleus, incus, stapes

Bones of middle ear

 

9

tensor tympani, stapedius

muscles of middle ear

 

10

Sound induced --------- of the tympanic membrane are transferred along a chain of 3 small bones (-------) to the -----window

 

 

Middle ear

Sound induced vibrations of the tympanic membrane are transferred along a chain of 3 small bones (ossicles) to the oval window

11

attached to tympanic membrane; attached to oval window

malleus vs. stapes

12

types of joints between ossicle bones

synovial joints

13

tf tensor tympani

increases the vibration of tympanic membrane via attachment to the incus(CN -V)

 

Middle Ear

tensor tympani

decreases the vibration of tympanic membrane via attachment to the malleus (CN -V)

14

Stapedius

increases the vibration of the stapes via attachment to the malleus

Stapedius

decreases the vibration of the stapes via attachment to the stapes

15

protect the ear from excessive vibration

tensor tympani and stapedius

16

area of the tympanic membrane is --- greater than the stapes attachment at the oval window.

area of the tympanic membrane is 15x greater than the stapes attachment at the oval window.

17

attached at oval window

stapes

18

differences magnifies the ------- per unit ----- of the stapes at the oval window, which is sufficient to move ------ within the cochlea.

differences magnifies the force per unit area of the stapes at the oval window, which is sufficient to move perilymph within the cochlea.

19

The perilymph within the cochlea moves from the ---- window toward the----window, in the bony cochlea.

The perilymph within the cochlea moves from the oval window toward the round window, in the bony cochlea.

20

membranous component of the cochlea

auditory receptor cells

deformed by Perilymph movement 

21

organ of corti.

auditory receptor cells

cochlea

22

cochlear duct

Membranous Cochlea

23

has endolymph

Membranous Cochlea

24

Filled with perilymph

Bony Cochlea

25

Consists of interconnected bony cavities

Bony Cochlea

26

(high in Na + , low in K + ); (low in Na + , high in K + )

perilymph; endolymph

27

location of the auditory receptor cells … Hair Cells

Membranous Cochlea

28

label the blanks

 

Q image thumb

A image thumb
29

Movement of the stapes deflects the membrane at the oval window

Perilymph movement deforms the membranous cochlea duct which contains the organ of corti with its auditory hair cells

This causes displacement of the perilymph within the bony cochlea

Movement of the stapes deflects the membrane at the oval window 

This causes displacement of the perilymph within the bony cochlea

Perilymph movement deforms the membranous cochlea duct which contains the organ of corti with its auditory hair cells

30

scala media 

cochlear duct

31

Q image thumb

A image thumb
32

tf cochlear duct is square

f

triangular

33

tips of the stereocilia are embedded in the ----- membrane (outer hair cells)

tips of the stereocilia are embedded in the tectorial membrane (outer hair cells)

34

Movement of the ------ membrane influences movement of the ------ and thus, impacts ------- release

Movement of the basilar membrane influences movement of the sterocilia and thus, impacts neurotransmitter (NT) releas

35

release of --- will excites CN -----

release of NT will excites CN-VIII

(occurs from basilar membrane when stereocilia is moved )

36

cochlear base 

high notes

Stiff 

37

 cochlear apex 

Relatively flexible , low notes

A image thumb
38

“Tonotopically” organized.

Basilar Membrane 

39

number of nerve fibers responding

frequency of neuronal firing

Coding of Intensity of the sound

(decibals)

40

location of sound

Coded within the CNS

CNS compares the timing of sounds reaching the two ears

41

Auditory Pathway

majoraity fibers cross to contralateral superior olive

42

cochlear nerve 

goes to spiral ganglion and then to cochlear nucleus

43

Superior olive is important in localization of sound

via the timing and intensity of input

44

lat lemiscus 

path through which fibers cross to inf colliculus in auditory path

45

Medial Geniculate Nucleus

last nucelus in audiotry pathway before goin to area 41

46

auditory pathway crosings

trapezoid bodies

inferior colliculus,

medial geniculate nucleus

and cerebral cortex

47

The trapezoid body (the ventral acoustic stria) is

part of the auditory pathway where some of the axons coming from the cochlear nucleus(specifically, the anterior cochlear nucleus) decussate (cross over) to the other side before traveling on to the superior olivary nucleus

48

Auditory Cortex

(41/42)

49

antiobiotic

destroy hair cells(ototoxic effects)

50