Special Senses - Hearing and the Vestibular System Flashcards Preview

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Flashcards in Special Senses - Hearing and the Vestibular System Deck (67):
1

Outer ear fxn

funnel sound waves into the ear

2

middle ear fan

impedance matching - sound wave has been moving through air, but now we are going to move it through fluid

3

inner ear

cochleas converts sound waves to action potentials

4

the two continuous fluid filled compartments of the cochlea

scala vestiboli and scala timpani

5

fluid inside the scala vestibuli and scala tympani

Perilymph

6

perilymph composition

simialar to the ECF
High Na, low K

7

Basilar and Reissner;s membrane create what chamber

scala media

8

the scala media is isolated from the _____ and is instead filled with ______

perilymph
endolymph

9

composition of endolymph

high in K, low in Na
will have a significant effect on the transduction of sound waves into action potentials

10

Perilymph
where
composition similar to
ion composition

scala vestiboli and scala timpani
CSF/ECF
High Na, low K

11

Endolymph
where
composition similar to
ion composition

scala media
intracellular fluid
high K, low Na

12

head motions are crucial for helping external ear funnel sound waves into ear. what do we do

turn our head towards the noise to improve the ability of the ear to collect sound waves (maximize the difference between ears for localization

13

The ______ transmit and amplify sound waves from tympanic membrane to _____

ossicles
oval window of cochlea

14

Inner ear physiology of sound

the impact of the stapes on the oval window causes the basilar membrane to vibrate at the same frequency of sound

15

the basilar membrane vibrates _____ with impact, _____ with release

down
up

16

high frequency sounds cause the maximum vibration of the basilar membrane where

closest to the oval window (short wavelength)

17

low frequency sounds cause the max vibration of the basilar membrane where

fastest away from the oval window, towards the helicotrema (long wavelength)

18

each hair cell is composed of a distinct arrangement of

shorter sterocilia that increase in length

19

are the stereo cilia true cilia

no

20

each stereo cilia is connected to another at the top by

an extracellular filamentous protein known as the TIP LINK
(so they all move as one)

21

During development, there is a since true cilium called

the kinocilium.

22

the tallest of the :hairs: on the hair cell

the kinocilium

23

the kinocilium ____ around the time of birth

degenerateds

24

when sound causes the basilar membrane to vibrate what happens in the tectorial membrane? how does this affect the hair cells?

the connections between the basilar membrane and the tectorial membrane cause the tectorial membrane to move as well

this motion bends the hair cells

25

If steriocilia are bent TOWARDS The kinocilium (or where it used to be) the hair cell

depolarizes

26

if the stereo cilia move away from the kinocilium, the hair cell

hyperpolarizes

27

bending the hair cells towards the kinocilium opens

K channels that depolarize the cell
- due to the composition of the endolymph, K enters the hair cells and causes it to depolarize

28

The path of auditory processing splits into

two parallel paths in the cochlear nuclei

29

The ventral path processes

temporal and spectral features of sound

30

the dorsal path integrates the

acoustic information with somatosensory information for localizing sound

31

medial superior olive generates

a map of the intramural time differences (how the sound arrived at the two ears differently) microseconds matter

32

lateral superior olive generates

a map of the intramural intensity differences (how the sound arrived at the two ears differently)
the amplitude of the ound when it reaches the scond ear is slightly reduced

33

time and intensity differences are crucial information in

determining where a sound originated from

34

the inferior colliculus

supresses information related to echoes and arrives at a final estimation of sound location on the horizon

35

the superior colliculus

takes the location data from the inferior colliculus and adds the third dimension to it VERTICAL HEIGHT to create the spatial map of the sound;s location

36

The primary auditory cortex A1 has a _____ representation of sounds

tonotopic

37

More rostral areas of A1 are activated by

low frequency sounds

38

more caudal areas of A1 are activated by

high frequency sounds

39

The Auditory Association cortex is composed of______. Purpose?

several different types of areas
has neurons that are activated by complex sounds. Purpose ois processing of complex sounds, i.e. music, identification of sound (naming) and speech

40

Linear acceleration occurs in

the horizontal or vertical plane

41

angular acceleration requires

rotation around one or more planes

42

Types of angular acceleration

can spin around vertical axis
can fall forward
can fall backward

43

In real life, most motions are

combinations of several accelerations

44

swelling where the three semicircular ducts connect

utricle

45

below the utricle

saccule

46

acceleration is detected by

semicircular ducts
utricle
saccule

each is oriented to be best at detecting acceleration in one of the planes

47

What type of fluid is found int the vstibular apparatus

endolymph (high K)

48

what type of fluid surrounds the vestibular apparatus

perilymph (high Na)

49

utrical detects

linear motion along horizontal plane

50

saccule detects

linear motion in a vertical plane

51

Horizontal aka lateral canals detect

horizontal turning motion

52

posterior semicircular canal detects

falling posterior
falling backwards

53

the anterior semicircular cana detects

falling anterior
falling foward

54

process of activating different vestibular organs

movement of hair cells in one direction is excitatory, movement in the opposite direction inhibits

55

in semicircular canals ____ is specialized for acceleration

ampulla

56

in utricle and saccule, the _____ is specialized for acceleration

macula

57

otolith organs

utricle and saccule

58

organs with cupula

semicircular ducts

59

how do we go from activating vestibular organs to sending information to brain

motion of the body (particularly the head) will produce motion of the endolymph in the appropriate vestibular organ, bending the hair cells in the ampullae or macula (depending on the type of motion) and activating the nerves

60

regardless of which way we are falling/moving, reflexes are designed to

keep our focus on the horizon (a spot directly in front of us)

61

as I spin, eyes rotate

horizontally until i can no longer physically focus on that spent, at which time they jump to pick a new spot

62

fall forward, eyes move

up

63

fall backward, eyes move

down

64

If the anterior semicircular canal is active, the ______ is activated while the ____ is inhibited

superior rectus m
inferior rectus m
eyes move up to continue to focus as you fall forward

65

if the posterior semicircular canal is active, the ___ is activated while the _____ is inhibited

superior oblique m
inferior oblique m
eyes move down to continue to focus on a point as you fall backwards

66

if the horizontal (lateral) semicircular canal is active, the ________ is active while the _______ is inhibited in the eye ipsilateral to the rotation.
The control lateral eye activates the ________ and inhibits the _______.

medial rectus
lateral rectus

lateral rectus
medial rectus

eyes move left or right to continue focus as you spin around

67

role of cerebral cortex and cerebellum in the integration of vestibular information and the control of gaze

the vast majority of the cortical and cerebellar involvement in the vestibulooptic reflexes is to suppress the reflex to allow for voluntary motion