physiology of hearing and balance Flashcards Preview

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Flashcards in physiology of hearing and balance Deck (25):
1

what does the external ear do?

collect sound waves

2

what does the middle ear do?

amplify sound waves

3

what does the inner ear do?

sound transducer and maintains balance

4

why is eustachian tube important?

ventilates middle ear and maintains equal air pressure across tympanic membrane

5

where are the ossicles?

middle ear

6

cochlea is for?

hearing

7

vestibule is for?

balance

8

what does the auricle do?

catches sound waves

9

where does the auricle send the sound waves?

deeper into the ear through the external acoustic meatus

10

what happens when sound waves reach the end of the external acoustic meatus?

they push the ear drum back and forth and make it vibrate. the vibrations are then passed onto the ossicles

11

what do the ossicles do?

they amplify the sound to make it stronger as they move into the fluid filled cochlea. they transmit the sound waves from the tympanic membrane to the cochlea

12

3 chambers in cochlea?

scala vestibuli
scala media
scala tympani

13

what is the important membrane in the cochlea?

basilar membrane

14

what happens in the basilar membrane?

the hairs in the membrane detect vibrations and transduce these into nerve impulses which pass to organ of corti.

15

what sounds are heard in the short stiff hairs at start of membarne?

high frequency sounds

16

what sounds are heard in the long wiggly hairs at start of membarne?

low frequency sounds

17

what happens in the organ of corti?

action potentials eventually sent through cochlear nerve, auditory pathwya to cerebral cortex

18

what is frequency?

number of waves that pass a certain point in a given time frame

19

what makes a high pitched noise?

faster numerous waves

20

what makes a low pitched noise?

slower and less waves

21

what does loudness depend on ?

amplitude

22

what is amplitude?

difference between the high and low pressure created in the air by that sound wave

23

what does the vestibular apparatus control?

balance

24

fluid in the vestibular apparatus is controlled by what?

head movement

25

how is balance controlled?

when your head moves in a certain way, the fluid in the semicircular canals will move in a certain way and stimulate hair cells which send action potential to the brain