Physiology of Hearing and Balance

Question 1

what is sound

Answer 1

a pressure wave caused by oscillating molecules - set in motion by vibration

Question 2

what does frequency of sound waves dictate

Answer 2

pitch
amplitude
intensity

Question 3

what frequencies of sound to humans perceive

Answer 3

20-20,000Hz

Question 4

how does the middle ear act as an amplifier mechanism

Answer 4

the ossicular chain acts as a leaver arm which has varying efficiency depending on the frequency of sound

Question 5

what is the Eustachian tube

Answer 5

ventilation pathway for middle ear mucosa

Question 6

what is the resting state of the cartilaginous part of the Eustachian tube

Answer 6

close

opened by the teens deli palatine and levator palatine muscles

Question 7

what do oval and round windows of the cochlea do

Answer 7

allow transmission of pressure waves in enclosed canal and vibration of the basilar membrane

Question 8

what runs inside the modulus

Answer 8

nerves to the ears

Question 9

what is the Scala media

Answer 9

bit in-between the Scala tympani and the Scala vestibuli

Question 10

what are the outer hair cells for

Answer 10

actually produce sound

Question 11

where is there a different ‘charge’ in the Scala media and Scala vestibuli

Answer 11

to maintain power to the sensory cells

Question 12

why can you get auditory processing problems when theres a blow to the temporal one

Answer 12

because it damages the primary auditory cortex

Question 13

when do you start to hear

Answer 13

18 week foetus

Question 14

when does a foetus respond to sound

Answer 14

week 26

Question 15

how is neonatal screening done

Answer 15

check both of the outer hair cells are working

Question 16

when is a cochlear implant useful

Answer 16

cochlear is present just not working

Question 17

at what age should a child be able to coo and recognise mother’s voice

Answer 17

3 months

Question 18

at what age should a child babble, turn to sound, make happy and sad sounds

Answer 18

6 months

Question 19

when should a child be able to make simple noises, mama/dada, follows instructions, turns to sound

Answer 19

12 months

Question 20

when should I child be able to say a few words eg. colours, animal sounds - recognises body parts

Answer 20

18 months

Question 21

when should I child be able to use two work phrases, 50+ words and understands questions and follows commands

Answer 21

24 months

Question 22

what systems imput to balance

Answer 22

visual 
proprioceptive 
vistibulospinal 
vestibule-ocular 
vestibular 
cardiovascilar

Question 23

what is the imputes for balance

Answer 23

vestibular system

Question 24

output of the balance system

Answer 24

Vestibulospinal

Question 25

what does the superior vestibular nerve supply in the inner ear

Answer 25

lateral/anterior SCC and utricle

Question 26

what does the inferior vestibular nerve supply in the inner ear

Answer 26

posterior SCC and sacule

Question 27

what happens when the inner ear hair cells moves towards

Answer 27

resting potential goes up

Question 28

what happens whin inner ear hair cells move away

Answer 28

resting potential goes down

Question 29

what happens whin inner ear hair cells move away from the biggest one

Answer 29

resting potential goes down

Question 30

how is it made sure any movement of the head is perceived

Answer 30

the steriocilia are orientated in all directions as the saccule and utricle are at right angle

Question 31

what is the vestibule-ocular reflex

Answer 31

when you turn to the right, the fluid in the cupola is moved to the left

that increases firing on the left side

ur gonna have to look it up

Question 32

what happens when the AP in one of the ears is lost

Answer 32

it tells the brain that theres spinning

Question 33

what is oscillopsia

Answer 33

no vestibular input

wobbly af eyes are moving n shaping

Question 34

what can cause oscillopsia

Answer 34

gentamicin toxicity

toxicity from chemo

Question 35

where does the vestibular nuclei have outputs to

Answer 35

vestibulospinal tract
medial and longitudinal fascicles and ocular muscles
medial leminscus and thalamus the cerebrum