More CANS

Question 1

What are the structures of CANS?

Answer 1

8CSLIMA
CN 8
Cochlear nucleus
Superior olivary complex
lateral laminiscus
inferior colliculus
medial geniculate body
a1

Question 2

what kind of receptors are our hair cells?

Answer 2

mechano receptors

Question 3

what pivots on stereocilia during mechanical stimulation/sheering

Answer 3

cross-linked actin filaments

Question 4

do stereocilia move independently?

Answer 4

no, they are interlinked and move as a whole bundle

Question 5

what do the tiplinks have

Answer 5

mechanically-gated cation channels normally open part of the time

Question 6

What causes the rush of potassium into the hair cell (depolarization)?

Answer 6

stereocilia are deflected shortest to tallest

Question 7

causes increased firing

Answer 7

depolarization

Question 8

causes decreased firing

Answer 8

hyperpolarization

Question 9

what is an important accessory structure?

Answer 9

tectorial membrane
aids in response to sounds

Question 10

what do our OHCs do

Answer 10

biological mechanical amplifiers

Question 11

describe upward scale of masking

Answer 11

low frequencies mask the high frequencies
low frequencies have a more gradual slope where high frequencies have a steeper slope

Question 12

main sensory/afferent fibers

Answer 12

IHC

Question 13

How many CN VIII fibers go to IHC

Answer 13

90-95%

Question 14

___ IHC synapses onto _____ different CN VIII fibers

Answer 14

1, 10

Question 15

amplifiers

Answer 15

OHC

Question 16

Receives ___ innervation from afferents

Answer 16

5-10%

Question 17

___ CN VIII fibers attaches to ____ OHCs

Answer 17

1, multiple

Question 18

divergent

Answer 18

goes from one hair cell to many nerve cells

Question 19

convergent

Answer 19

goes from a bunch of hair cells to one nerve cell

Question 20

information ____ to many neurons from one IHC

Answer 20

diverges

Question 21

information from many OHC _____ on to one neuron

Answer 21

converge

Question 22

What type of cell do we mostly see on CN VIII fivbers? Explain them

Answer 22

bipolar - two parts, dendrite to pick up and bring it along pathway to cell body then axon going down to terminal boutons to synapse
cell body = spiral ganglion
receive info from cochlea
spiral ganglion = cell body in cochlea spiral
axon runs through IAC (CNS) - cochlear nucleus

Question 23

What are key factors of AP?

Answer 23

Voltage-gated ion channels
All or none depolarization
Self-propagating—one spot triggers the next spot
Moves forward only (naturally) due to absolute and relative refractory periods
Jumps by salutatory conduction from node of Ranvier to the next node

Question 24

How do we encode?

Answer 24

frequency, intensity, firing patterns for onset, duration, offset, envelope

Question 25

Describe frequency encoding

Answer 25

tonotopic organization and phase locking (related to timing and frequency)

Question 26

Describe intensity encoding

Answer 26

rate of firing of action potentials, how many fibers are firing and which fibers are firing

Question 27

A plot which represents the “tuning” or frequency specificity of response

Answer 27

tuning curve

Question 28

What responds to get tuning curves?

Answer 28

BM, nerve fiber/cell, psychoacoustic response of a PT

Question 29

firing patterns over time

Answer 29

post-stimulus time histogram