Hearing Flashcards Preview

FBN > Hearing > Flashcards

Flashcards in Hearing Deck (17)
1

What is sound

longitudinal waves - rapid variation of air pressure

2

What is wavelength and frequence

WL - distance between two peaks
FR - rate the pressure cycles compression > refraction

3

normal air pressure?

100kpa

4

what is a decibel?
100kpa =

log
2 mil decibels

5

role of the pinna

gathers air from around and funnels into eardrum

6

what is the cochlea

fluid filled spiral canal separated by a flexible membrane

7

differences between two sides of the cochlea

start narrow and stiff end wide and compliant

8

what does the wave in the cochlea determine

frequency

9

where is the organ of corti

within the scalia media

10

shapes of inner hair cells and outer hair cells

inner - fat
outer - thin

11

what to the stereocilla look like of inner and outer hair cells

inner hair cells - in a line
outer - rows of 3 in dome shames

12

how do the hair cells work

the hair cells bend one way causing depolarisation and bend another way causing repolarisation. the hair cells are attached to afferent neurones so APs are generated during depolarisation (right excitation left inhibition)

13

what are transduction links

in hair cells join the cillia together causing increased ion entry making the depol / hyperpol bigger

14

tuning fork?

high kh lower decibels and at a higher decibels at a lower hhz

15

What is the cochlear amplifier

theyre motile therefor increased vibrations in the basilar membrane - amplifies quiet sound not loud

16

describe the two types of hearing loss

conductive - abnormality before cochlea
Sensorineural- in cochlear or auditory nerve (loss of hair cells or hair cell function)

17

what is Deafferentation and when does it occur

detachment of nerve fibres from inner hair cells
occurs in mild noise exposure might get worse with age
cant detect it - invisible to audiologists