l10 ear

Question 1

external auditory meatus

Answer 1

s shape (prevent flies going in)
2.5 cm length
amplify 3kHz

Question 2

Tympanic membrane

Answer 2

• Lie obliquely
  - Slightly concave
  - 0.1 mm thick
  8 to 10 mm diameter

Question 3

middle ear include

Answer 3

3 ossicles (incus, malleius, stapes)
2 muscle (stapedius + tensor tympanic)

Question 4

joint between incus and stapes

Answer 4

movevable joint, for amplifying sound

Question 5

stapedius + tensor tympanic func

Answer 5

dampening sound
stapedius, pull stapes away from oval window
tensor put tension on malleus (vibrate less)

Question 6

nerve stapedius

Answer 6

facial 7

Question 7

nerve tensor tympanic

Answer 7

mandibular of trigeminal 5

Question 8

2 muscle is reflex, how?

Answer 8

when loud noise enter, signal send to brainstem and send decision back for these muscle to dampen sound

-> 40 msec delay
-> you still hear very loud at the first 40 msec (not significant unless SUPER LOUD - GUN SHOT SOUND)

Question 9

Bony Labyrinth

Answer 9

hard-walled bony cavities
-= INCLUDE LOW K+ PERILYMTH

Question 10

Membrane Labyrinth

Answer 10

INSIDE BONY
- inside these include endolymph (high k+)

Question 11

Cochlea is where mechanical (vibration) signal -> electrical (impulses) -> transduction

describe?

Answer 11

Coils 2.5 times around modiolus
10mm in size
25mm uncoiled

Question 12

hair cell at cochlear, has axon goin to brain,

Question 13

Cochlea duct

Answer 13

partition, separating the cochlea into 3 spaces
scala med
(endolymph)

Question 14

Above call

Answer 14

scala vestibulli (peri)

Question 15

Below cal

Answer 15

scala tympanic (peri)

Question 16

Helicotrema

Answer 16

fluid of scala vestibuli and tympani are continuous

Question 17

membrane separate media from scala tympanic

Answer 17

basilar membrane

Question 18

on top basilar is

Answer 18

organ of corti

Question 19

organ of corti has

Answer 19

lots of tissues connect each other there, lots of haircell here too

3 out
1 in

Question 20

low freq to what hair cell

Answer 20

near apex

Question 21

high freq to what hair cell

Answer 21

near base (narrow)

Question 22

what we haer conciously from

Answer 22

inner hair cell

Question 23

basilar has haircell send signal to

Answer 23

cranial 8

Question 24

open

Answer 24

k+ get inside, making action potential????? check again

Question 25

amplitude and pattern

Answer 25

Each neuron has different threshold Amplitude increase -> number of neuron activate by hair cell increase Ø Pattern of neuron send signal to brain (sound intensity)

Question 26

superior olive function

Answer 26

utilise that sound arrive at slightly different time - > calculate angle/location of sound -> horizontal

Question 27

dorsal path of nuclei function

Answer 27

verticle sources of sound - delay between direct and reflected sound, how it bounce through pinna

Question 28

inferior colliculi

Answer 28

- Auditory map - Analyse pattern of sound: know by pattern of sound if it is female or.... - Processing complex sound and handling echoes, just take the first signal and remove others

Question 29

central auditory pathway

Answer 29

vestibulacochlea nerve -> cochlear nuclei -> dorsal: to inferior coliculous ventral: to bilateral superior olivary or lateral leminicus to inferior coliculous to medial geniculate nuclei -> cortex

Question 30

medial SO

Answer 30

calculate angle, which ear sound came from (horizontal claim)

Question 30

inferior

Answer 30

vertical sources of sound, based on how sound bounce in pinna, direct or indirect

Question 31

inferior colliculi func

Answer 31

map of sound (where sound is form) analyse pattern of sound: familiar? female voice? handling echoes

Question 32

primary cortex func

Answer 32

receiving both ears

Question 33

secondary left func

Answer 33

meaning comprehension

Question 34

secondary right function

Answer 34

non verbal aspect, emotional