11-13. Auditory system

Question 1

The stapes converts pressure waves in air to fluid via the:

Answer 1

oval window

Question 2

where is the basilar membrane?

Answer 2

cochlear

Question 3

what do we use for detecting linear acceleration?

Answer 3

saccule

Question 4

which responds best to movements in the horizontal plane? utricle or saccule?

Answer 4

utricle

Question 5

where would you find the otolith crystals?

Answer 5

ototholic gelatinous membrane

Question 6

what nerve carries sensory info from the otolith organs?

Answer 6

CN VIII

Question 7

definition of sound

Answer 7

audible variations in air pressure

Question 8

what is intensity

Answer 8

the amplitude of a wave - the difference in pressure between compressed and rarefied pathed of air in a sound wave.

Question 9

what does intensity determine?

Answer 9

loudness

Question 10

what is frequency?

Answer 10

The number of waves per second (Hz)

Question 11

what does frequency determine?

Answer 11

pitch

Question 12

name of external ear

Answer 12

auricle

Question 13

channel from external ear to tympanic membrane

Answer 13

external acoustic meastus

Question 14

what separates the outer and middle ear?

Answer 14

tympanic membrane

Question 15

is the middle ear fluid or air?

Answer 15

air

Question 16

names of 3 auditory ossicles?

Answer 16

malleleous, incus, stapes

Question 17

what does the stapes hit ?

Answer 17

oval window

Question 18

trunk of the cochlear

Answer 18

vestibule

Question 19

what is at the end of the vestibule?

Answer 19

semi-circular canals

Question 20

what occurs in the infection of the middle ear?

Answer 20

fluid builds up which prevents the movement of the auditory ossicles

Question 21

where is the receptor organ for hearing?

Answer 21

cochlear

Question 22

name of receptor organ for hearing?

Answer 22

spiral organ of Corti

Question 23

what does the spiral organ of Corti contain?

Answer 23

hair cells

Question 24

name 2 muscles of middle ear

Answer 24

tensor tympani

stapedius

Question 25

describe the attenuations reflex

Answer 25

the contraction of the ear muscles in respond to a loud noise. this prevents movement of the ossicles to avoid damage to the oval window.

Question 26

what can cause conductive hearing loss (2)

Answer 26

1. scar tissue from infection | 2. otosclerosis (proliferation of bone tissue)

Question 27

describe the process of sound in the basilar membrane in steps

Answer 27

1. pressure changes move oval window 2. moves perilymph in scala vestibuli 3. move reissner's membrane 4. moves endolymph in scala media 5. causes vibrations in the basilar membrane

Question 28

where are high freq located on the basilar membrane?

Answer 28

at the base

Question 29

3 spaces in the inner ear

Answer 29

1. scala vestibuli 2. scala media 3. scala tympani

Question 30

name of fluid in 1. scala vestibuli + tympani 2. scala media

Answer 30

1. perilymph | 2. endolymph

Question 31

name of membrane which is below the scala vestibuli

Answer 31

reissner's membrane

Question 32

which 2 membranes do the hair cells of the organ of corti lie?

Answer 32

basilar and tectorial

Question 33

function of vestibular system

Answer 33

balance and movement

Question 34

2 otolith organs

Answer 34

utricle and saccule

Question 35

name the 3 semicircular canals

Answer 35

anterior, posterior, horizontal

Question 36

what type of acceleration do the ototlith organs detect?

Answer 36

linear

Question 37

what type of acceleration do the semi-circular canaals detect?

Answer 37

angular/ rotational

Question 38

what are the semi-circular canals filled with?

Answer 38

endolymph

Question 39

what type of movements do the ... detect? i) utricle ii) saccule

Answer 39

i) horizontal | ii) vertical

Question 40

which 2 layers do the hair cells lie between?

Answer 40

otolith gelatinous membrane and the macula membrane

Question 41

what is contained within the otolith membrane?

Answer 41

otolith crystals

Question 42

function of otolith crystals

Answer 42

allows a change in density of the membrane when we move - giving info about our orientation

Question 43

what is the ampulla?

Answer 43

swelling at base of semi-circular canals which contain the hair cells

Question 44

what is the cupula?

Answer 44

gelatinous membrane which contains sensory processes (hairs)

Question 45

movement of the stereocilia towards the kinocilium leads to opening or closing of the tip links?

Answer 45

opening

Question 46

what does the opening of the stereocilia links lead to in terms of K+ and depolarisation?

Answer 46

K+ influx into cell, depolarisation

Question 47

bending sterocilia away from the kinocilium leads to what?

Answer 47

reduced Ca2+ influx - below baseline rate

Question 48

Rotation of the head to the left will reuslt in activation of which horizontal canal; right or left?

Answer 48

left

Question 49

for a sound of 300Hz , which auditory processing would be used?

Answer 49

Both tonotopy and phase locking

Question 50

If a 6kHz sound came from the left side of the body what would we see; a) Excitation in right MSO b) Excitation in left MSO c) Excitation in right LSO d) Excitation in left LSO

Answer 50

d)Excitation in left LSO

Question 51

A person is turned to the left for 30 seconds (spinning). what would we see immediately after the rotation stops? saccadic (fast) movements of the eye to the right or the left? which way is the endolymph turning at this point?

Answer 51

right as endolymph is moving to the left