Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

AUDE 5160 - Anatomy > Inner Ear Review 3 > Flashcards

Inner Ear Review 3 Flashcards

(74 cards)

Start Studying
1
Q

What is the partition consisted of?

A

BM, tectorial membrane, organ of corti

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Tonotopic arrangement

A

Different regions of the basilar membrane vibrate at different sinusoidal frequencies due to variations in thickness and width along the length of the membrane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

he place of basilar membrane motion is thought to be directly related to perceived

A

pitch

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Process of the hair cells transmitting NT to the cochlear nerve

A
  1. Tectorial membrane moves and stimulates the stereocilia
  2. Links on the stereocilia open to allow potassium to flow into the cell (depolarizes)
  3. Calcium flows into the cell through ion channels
  4. Triggers glutamate+ to go to the synaptic cleft
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Process of the refractory period after a hair cell fires

A
  1. Potassium is reabsorbed into the cortilymph
  2. Stria vascularis takes up potassium again to recycle it into the endolymph
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

If the fluid moves the hair cells from tall to short, this will:

A

Inhibit the influx of potassium (hyperpolarize)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What factors help us sensory code sounds?

A

intensity frequency pitch

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Why do we need the hair cells to “sharpen” the incoming signals?

A

to differentiat between pitches/frequencies (aka active mechanism)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Absolute refractory period

A

time during which another action potential is impossible; limits maximal firing rate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

relative refractory period

A

the period of time following an action potential, when it is possible, but difficult, for the neuron to fire a second action potential, due to the fact that the membrane is further from threshold potential (hyperpolarized)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

4 characteristics of an action potential

A
  1. Self propogating
  2. Forward transmission
  3. Unidirectional
  4. No degradation over time
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

the place of the basilar membrane motion is related to ____

A

frequency and pitch

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

the BM is ____ and ____ at the base

A

narrow and stiff (high frequencies)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

the BM is ____ and ____ at the apex

A

wide and floppy (low frequencies)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what type of frequencies are more suceptible to damage?

A

high frequencies (at the base, get all input all the time)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

primary function of inner hair cells

A

send information about sound to the brain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

axosomatic

A

nerves that connect an axon to a soma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

shape of outer hair cells

A

test tube shaped, don’t have a bulge

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

shape of inner hair cells

A

flask shaped, have a bulge in the middle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

what are the main afferents?

A

IHC

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What are the main efferents?

A

OHCs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is the kinocilium?

A

guiding body for the hair cell stereocilia to align during embryologic development

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What happens to kinocilium after birth?

A

becomes rudimentary

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

stereocilia are arranged by what factor

A

height

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
stereocilia connect to each other through
tips and side links
26
What is one major difference in OHC?
lined with prestin (matrix like format and form of muscle tissue for movement)
27
how many OHC do humans have?
12,000
28
How many IHC do we have (in total)?
4,000
29
Are frequency ranges among different species the same?
no, vary due to the size of hearing systems
30
most common type of cochlear damage
OHC damage
31
what type of loss is associated with OHC damage
sensory HL, 40 dB loss, mild to moderately severe
32
if both IHC and OHC are gone, what degree of hearing loss will we have?
severe to profound
33
most common neurotransmitter in ear
glutamate
34
What kind of sound stimuli do the OHC amplify?
low (0-40dB)
35
What is our auditory accessory structure?
tectorial membrane
36
Is the receptor potential directly transmitting information to the receptor neuron?
No, it doesn't directly transmit information... goes through the synaptic cleft
37
What excites the neuron
neurotransmitter
38
If fluid moves the hair cells from short to tall, this will:
Excite the system, cause an influx of potassium (depolarize)
39
What do we know about the action potentials of a hair cell at rest?
there are still firings happening
40
What physical property of sound determines the displacement of the basilar membrane?
frequency
41
How is neural firing different than cochlear nerve firing?
Sodium influx in brain instead of potassium firing in cochlea, potassium outflux in brain
42
3 factors that influence encoding
intensity frequency firing code
43
three factors when encoding intensity
rate how many fibers
44
2 factors when encoding frequency
tonotopic organization phase locking
45
4 factors related to the firing pattern codes of OHC
Onset duration offset envelope
46
what makes a tuning curve "sharp" ?
amplification of the OHC (active mechanic amplifiers)
47
if we have damage to the OHC, what will we see on a tuning curve?
"broad" tuning, not sharp
48
what do our efferent fibers do for the inner ear system?
modulate / modify the OHC activity
49
in what ways do the efferent fibers modulate the OHC activity?
- reduce masking - selective attention - protect from intense sound - balance input from both ears
50
how do OHC improve our sensitivity?
they make response thresholds lower (compress them --> nonlinear system)
51
what are the cochlear receptors
IHC
52
what do the IHC do?
generate receptor potentials (afferent)
53
what crosses the synaptic cleft to stimulate CN 8 nerve fibers?
neurotransmitter (most common in aud system is glutamate+)
54
at what point is an action potential generated?
when there is sufficient neurotransmitter
55
how is neural firing different than cochlear firing?
NaK pump instead of just K (potassium)
56
what concept explains why low frequencies can mask high frequencies but not vice versa?
upward spread of masking
57
can a 200 Hz tone maska 1,000 Hz tone?
yes, upward spread of masking
58
what do we know about the lowest point of the graph while looking at a tuning curve?
it is the characteristic frequenchy
59
what is a PSTH
post-stimulus time histogram
60
how do we graph a post-stimulus time histogram?
number of firing neurons on the y axis and time on x axis in milsec
61
what does a "primary" or "primary-like" PSTH look like?
rest - peak - rest (initial spike and nothing else)
62
describe a "pauser" response (PSTH)
spike -- pause -- buildup (primary with a pause)
63
describe an "onset-chopper" response (PSTH)
spike -- rest -- spike -- rest -- spike -- rest (increasing rest thresholds)
64
is there only one type of cell in the cochlear nuclei?
no, there are pyramidal, octopus, stellate, spherical, and globular
65
what are 2 excitatory neurotransmitters in the AVS
glutamate and aspartate (amino acids)
66
what are 2 inhibitory neurotransmitters in the AVS
GABA and glycine
67
what are 2 neurotransmitters in the "efferent" AVS pathway
acetylcholine and noradrenaline
68
8CSlima
- 8th nerve - cochlear nucleus - superior olivary complex - lateral lemniscus - inferior colliculus - medial geniculate body - auditory cortex (A1)
69
What are the two largest categories of ototoxic drugs?
aminoglycocide and some members of the platinum chemotherapy drug family (carboplaton)
70
Best describe the sodium-potassium pump
The main function of the pump is to maintain the resting potential by actively moving sodium out of the cell and potassium back in to restore the proper balance.
71
Based on the 5 important functions of cell membrane proteins, clearly describe 3 of the important functions of such proteins that are on or in the cell membranes?
One important function of cell membrane proteins is that they have transmembrane ion channels that determine the electrical activity of the cell. Another important function of cell membrane proteins is that they act as enzymes to catalyze biochemical reactions. Cell membrane proteins also act as carrier proteins to help things cross the cell membrane. These carrier proteins can either be passive or active transport. When a carrier protein is an active transporter, it requires ATP.
72
Briefly state two ways in which auditory nerve fibers are able to encode the frequency of an auditory stimulus.
Auditory nerve fibers encode frequency of auditory stimulus by the tonotopic arrangement of the cochlea. Different regions of the basilar membrane vibrate at different sinusoidal frequencies based on the thickness and width along it. The basilar membrane is designed so that it has a best region to vibrate for every frequency. For example, how high frequencies resonate best at the base and low frequencies closer to the apex. Phase-locking-with action potential firing locking to a specific phase of incoming sound
73
When an auditory stimulus reaches the cochlea what occurs to excite inner hair cells?
Potassium flows in through the open ion channels to depolarize the cell, causing a receptor potential
74

AUDE 5160 - Anatomy (16 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions