Auditory system

Question 1

the boundry b/w the outer and middle ear

Answer 1

tympanic membrane

Question 2

3 small bones of middle ear

Answer 2

• malleus
• incus
• stapes

Question 3

casts a “shadow” to give an intensity difference for spatial resolution (distinguish if sound is behind/in front of you/etc)

Answer 3

head and Pinna

Question 4

shadow things workds only at what types of frequency

Answer 4

high frequency

Question 5

the pinna and concha can act as a ( )

Answer 5

resonator

Question 6

the frequency where we can distinguish language (b/w specific consonants)

Answer 6

2,000-5,000 Hz

Question 7

transfer from a low to high impedance medium is accomplished by:

Answer 7

1) focusing force on the tympanic membrane to the oval window (17X amplification)
2) lever action of the bones (1.3X amplification)

Question 8

middle ear muscle: cause the malleus to stiffen the tympanic mebrane

Answer 8

tensor tympani

Question 9

middle ear muscle: cause the stapes to withdraw from the oval window

Answer 9

stapidius

Question 10

prevent damage from loud noises

Answer 10

tensor tympani & stapidius

Question 11

cochlea contain which two holes?

Answer 11

oval window and round window

Question 12

when cut open, the cochlea is composed of what three components?

Answer 12

1) scala vestibuli
2) scala tympani
3) scala media

Question 13

The organ of Corti is composed of the ( )

Answer 13

tectorial membrane

Question 14

Hair cells under the tectorial membrane sit over a specialized membrane, the ( )

Answer 14

basilar membrane

Question 15

Do hair cells fire AP?

Answer 15

no, they only detect them

Question 16

stereocilia are connected with structures called ( )

Answer 16

“tip links”

Question 17

The sheering of ( ) causes stimulation

Answer 17

stereocilia

Question 18

the ( ) vibrates and it is the sheeing force of the hair cells against the tectorial membrane that stimulates the stereocilia

Answer 18

basilar membrane

Question 19

the molecular sensors are ( )

Answer 19

K+ channels

Question 20

the K+ channels have a ( ) that can increase or decrease depending upon the direction of the sheering force

Answer 20

basal activity

Question 21

the hair cells do not fire AP but ( ) in response to stimuli

Answer 21

oscillate their membrane potential

Question 22

K+ levels are ( ) where the stereocilia are & ( ) where the cell body is

Answer 22

• high

- low

Question 23

What ion both depolarizes and repolarizes the cell?

Answer 23

K+

Question 24

lesions that occur in the nervous system post-cochlear nucleus often leads to an overall ( )

Answer 24

depression in hearing/sound processing

Question 25

sound is the compression and rarefaction of ( )

Answer 25

air pressure

Question 26

the compression wave causes the ( ) to push against the oval window, causes a compression in the scala vestibuli, the compression goes to the end of the ( ), around the hellicotrema, and ultimately pushes against the ( )

Answer 26

- stapes - cochlea - round window

Question 27

it is the ( ) vibrating that causes the sheering force of the hair cells against tectorial membrane

Answer 27

basilar membrane

Question 28

frequency encoding that involves the basilar membrane thickens and widens away from the oval window --> pitches vibrating at different regions

Answer 28

tonotopic mapping

Question 29

tonotopic mapping: hi frequency encoded at ( ), low frequency at ( )---which frequency does this work best at?

Answer 29

- base - apex - hight

Question 30

what range is human hearing most sensitive?

Answer 30

1,000-5,000 Hz

Question 31

the ( ) in the cochlea allows for a prosthetic device that transduces sound into electrical signals that can directly stimulate neuronal cells

Answer 31

tonotopic map

Question 32

spatial localization: low frequency

Answer 32

phase shift

Question 33

spatial localization: high frequency

Answer 33

intensity (shadowing)

Question 34

frequency encoding: low frequency

Answer 34

volley theory

Question 35

frequency encoding: high frequency

Answer 35

tonotopic map

Question 36

( ) are the primary sensors

Answer 36

inner hair cells

Question 37

( ) have many efferent connections and apparently adjust the mechanical properties of local regions

Answer 37

outer hair cells

Question 38

phenomenon: a small microphone in the ear can actually detect sound generated from the organ, presumably thru the inner/outer hair cell feedback mechanism

Answer 38

otoacoustical emissions (OAE)

Question 39

phase locking (volley theory) ratio

Answer 39

1:1

Question 40

the phase difference between the two ears (the ear closer will reach the peak of the wave slightly sooner)

Answer 40

phase shift

Question 41

because potassium concentration is high in the ( ) but low in the ( ) and cell surrounding, K is used to both depolarize and repolarize cell

Answer 41

- endolymph | - perylymph

Question 42

relative to perilymph, the cell is ( )mV and the endolymph is ( )mV potentials

Answer 42

-45mV; +80mV

Question 43

system is keeping up when neurons firing at a certain rate

Answer 43

volley theory

Question 44

louder on side of ear the sound is being generated

Answer 44

intensity

Question 45

basis of volley theory

Answer 45

phase locking

Question 46

ability of a system to keep up

Answer 46

phase locking

Question 47

starts in right ear then goes to left ear

Answer 47

phase shift