Neuro Exam 1 Part 3

Front 1

fluid contained by membranous labyrinth?

Back 1

K rich endolymph

Front 2

fluid contained by bony labyrinth?

Back 2

Na rich perilymph

Front 3

2 components of the membranous labryinth?

Back 3

cochlea
vestibule

Front 4

what is the cochlea?

Back 4

fluid filled coil of hose
sensory organ invoved in hearing
-cochelar nerve exit

Front 5

what is the vestibule

Back 5

sensory organ involved in balance
-vestibular nerve exist from it

Front 6

Which CN is involved in hearing/balance?

Back 6

vestibulochlear nerve (CNIII)

Front 7

Pinna

Back 7

"ear" that directs sound waves into the external auditory meatus

Front 8

tympanic membrane:
-location
-function

Back 8

-at the end of the external auditory meatus
-moves back and forth as sound waves strike it, transferring movement to middle ear osicles

Front 9

name middle ear ossicles

Back 9

maleus
incus
stapes

Front 10

what is the oval window

Back 10

stapes moves in and out of this window= waves in fluid filled cochela

Front 11

round window

Back 11

fluid waves in cochlea terminate here, exciting sensory cells

Front 12

saccule

Back 12

part of vestible
linear acceleration in vertical direction

Front 13

utricle

Back 13

part of vestibule
linear acceleration in horizontal directio

Front 14

semicircular canalas

Back 14

part of vestibular
detect rotation acceleration w/ crista, sensory organ

Front 15

What are the primary sensory cells in the middle ear? what are they made of?

Back 15

hair cells
stereocilia

Front 16

Tallest stereocilia?

Back 16

kinocilium

Front 17

What happens when hairs are displaced toward kinocilium

Back 17

hair cell excites
tip links= open cation channels= K from endolymph into cell
more nt

Front 18

What happens when hairs are displaced away from kinocilium

Back 18

Inhibited
cation channel springs shut
less nt

Front 19

What happens when hairs are displaced orthoganoly from kinocilium

Back 19

there is no change

Front 20

where are the cell bodies of cells for the vestibule?

Back 20

scarpa's ganglion

Front 21

Where are the cell bodies of cells for the cochlea?

Back 21

spiral ganglion

Front 22

How does the semicircular canal work

Back 22

Crista bulges into canal
hairs on crista are embeded in gelatinous cupula
Head rotates, acnal rotates in same direction
endolymph doesn't move= pushes cupula in opposite direction

Front 23

How do utricle and saccule work?

Back 23

They have hairs embedded in a gelatonous otolith membrane

otoconia (calcium carbonate crystals) sit on otolith membranes

Body accelerates, otoconia don't move= hair is forcesd in oposite direction

Front 24

Orientation of kinocilia:
utricle
saccule
semicircular canal

Back 24

utricle- different
saccule-different
semicircular- all same direction

Front 25

maintaining the head in a tilted position produces the same effects as __?

Back 25

linear acceleration

Front 26

Pathway of signals from vestinular sensory organs

Back 26

1. vestibulocochlear nerve (CN8)
2. synapse on vestibular nuclei in pons
3. project to spinal cord, CN nuclei that control eye movement, and the cortex via the thalamus

Front 27

Vestibulospinal system allow?

Back 27

maintaining balanced, upright posture

Front 28

Vestibulospinal system?

Back 28

1. lateral vestibulospinal tract= project ipsilaterally to motor nuerons in all levels of the spinal cord= move body to maintain posture

2.medial vestibulospinal tract= project bilaterally to motor neurons in cervical spinal cord= adjust head and neck posture

Front 29

Vestibulo-ocullar system allows?

Back 29

maintaining steady gave even when head is moving

Front 30

Vestibulo-ocular revlex if head rotates to left

Back 30

1. head rotates left
2. left horizontal semicircular canal
3. activation of left vestibular nucleus
4. left vestibular nucleus projects to contralateral abducens nucleus (VI)
5. abduces sends fibers to activate latera rectus muscle
6. abducens sends fibers (medial longitudinal fasiculus) to cross the midline and go to the occulomotor nucleus (CNIII) which activates the medial rectus muscle)
7. eye moves right

Front 31

goal of thalamocortico vestibular system

Back 31

give concious spatial orientation and self motion

Front 32

pathway of thalamocortico vestibular system

Back 32

1. vestibular nuclei to VPL
2. VPL to 3b of S1 and to Area 2 of parietal cortex

Front 33

nystagmus

Back 33

slow VOR-mediate eyemovement followed by quick resetting eyemovements

Front 34

normal response to constant rotation is nystagmus that beats in the same/opposite direction of motion?

Back 34

same

Front 35

Caloric stimulation test: warm water into left ear

Back 35

1. warm= activates left semicircular cnal
2. should have left beating nystagmus

Front 36

caloric stimulation test: cold water into left hear

Back 36

1. cold= inhibits left semicircular canal
2. right beating nystagmus

Front 37

Patient comes into office with constant, right-beating nystagmus: what does this indicate?

Back 37

lesion to left semicircular canal

Front 38

fxns of the middle ear ossicles?

Back 38

1. amplify sound pressure waves
2. impedance matching- transfer sound energy into fluid wave energy

Front 39

____ is the spance between the eardrum and the labrinth

Back 39

middle ear

Front 40

___ connect the middle ear to pharynx

Back 40

eustachain tube

Front 41

ostoclerosis

Back 41

disease of middle ear
overgrowth of bone/tissue= ossicles movement restrictited

Front 42

otitis media

Back 42

middle ear infection= inflammation that often blocks the eustachian tube

Front 43

scala vestibuli

Back 43

part of coclea that contains perilymph

Front 44

scala tympani

Back 44

part of cochlea that contains perilymph

Front 45

scala media

Back 45

part of cochlea that contains endolymp

Front 46

helicotrema

Back 46

at apex of cochlea where scala vestibuli and scala tympani connect

Front 47

What happens when stabes is forced into motion

Back 47

pushed into oval window
periymph waves thru scala vestibuli, helooctrema and into scala tympani
buldge in round window

this fluid also displaces basilar membrane, disturbing scala media
hair cells embeded in ogan of corti get shoved into tectorial membranes
channels open
K flows in from endolyph
spiral ganglion activates cochlear nerve

Front 48

Inner hair cells

Back 48

in cochlea
mediate hearing, signals to brain stem

Front 49

outer hair cells

Back 49

in cochlea
moderate firing of inner hair cells by altering their own shape/location in tectorial membrane

Front 50

otoacoustic emission

Back 50

sound made when outer hair cells change shape

Front 51

basilar membrane of cochlea responds to ____ at apex?

Back 51

low frequency sound (floppy)

Front 52

basilar membrane of cochlea responds to ____ at base?

Back 52

high frequency sound (stiff)

Front 53

place code?

Back 53

place in cochlear membrane /type of hair cell determines preffered frequency (high or low)

Front 54

rate code?

Back 54

cochlear nerve fibers an action potential at a frequency equal to the sound that stimulates them

Front 55

Auditory pathway

Back 55

1. signal from cochlea
2. vestibulocochlear nerve
3. brainstem- synapse on cochlear nuclei
4. sends info bilateraly via the trapezoid body to the superior olivary complex
5. projects as lateral leniscus to inferior colliculus
6. projects to medial geniculate nucleus
7. projects to A1 (primary auditory cortex/ heschl's gyrus) on superior back of temporal lobe

Front 56

fxn of medial superior olive

which type of frequency?

Back 56

localizes sound by detectint interaural time difference= knows if sound if from left or right

best for low frequencies

Front 57

fxn of lateral superior olive?

Back 57

localizes sound by detecting teraural intensity difference= intensity shows if sound is from left or right

best for high frequencies

Front 58

fxn

Back 58

1= cerebellum
2= brain stem
3= labryinth

Front 59

fxn

Back 59

Primary auditory cortex- recieves info from MGN, on superior bank of temporal lobe

Front 60

fxn

Back 60

Vestibular nerve- carries balance info from the sensory structures of the vestibule to the brainstem

Front 61

fxn

Back 61

cochlear nerve- carries auditory info from the cochlea to the brainstem

Front 62

Fxn?

Back 62

Vestibulochoclear nerve (CN 8)- carries jxn of vestibular nerve and cochear nerve

Front 63

fxn

Back 63

Semicircular canal- detec rotational acceleration

Front 64

fxv

Back 64

Utricle- detects linear acceleration in the horizontal direction

Front 65

Fxn?

Back 65

saccule=-detects linear acceleration in the verticle direction

Front 66

Back 66

Vestibule

Front 67

Back 67

cochlea

Front 68

Back 68

Utricle
1= otoconia
2= hair cells
3= sterocilia
4= afferent processes of CNVIII

Front 69

Fxn

Back 69

Vestibular nuclei- synapse site of signals from vestibular sensory organs

Front 70

Back 70

Vestibuloar occular nerve

Front 71

Back 71

Inferior cerebral peduncle

Front 72

fxn

Back 72

Abducens nerve- VOR (sends fibers to rectus muscles of the eye)

Front 73

fxn

Back 73

Abducens nerve- VOR (sends fibers to rectus muscles of the eye)

Front 74

Fxn

Back 74

Medial longitudinal fasiculus- receives fibers from abducens nerves and activates the CNIII (medial rectus) and CN IV

Front 75

Fxn

Back 75

Medial longitudinal fasiculus- receives fibers from abducens nerves and activates the CNIII (medial rectus) and CN IV

Front 76

Fxn

Back 76

Trochlear nerve- recieves fibers from Medial longitudinal fasiculus

Front 77

Fxn

Back 77

Trochlear nerve- recieves fibers from Medial longitudinal fasiculus

Front 78

Fxn

Back 78

Medial longitudinal fasiculus- receives fibers from abducens nerves and activates the CNIII (medial rectus) and CN IV

Front 79

fxn

Back 79

Occulomotor nucleus- recieves fibers from medial longitudinal fasiculus and activates the medial rectus

Front 80

Back 80

cochlea

Front 81

Back 81

Cochlear nerve

Front 82

Back 82

vestibular nerve

Front 83

Back 83

malleus

Front 84

Back 84

stapes

Front 85

Back 85

Eustachian tube

Front 86

Back 86

Scala vestibuli

Front 87

fxn

Back 87

Basilar membrane- displaced sterocilia of hair cells to shear into the tectorial membrane

Front 88

fxn

Back 88

Tectorial membrane- when hair cells enter channels open and K from endolymph flows in causing excitation

Front 89

fxn

Back 89

Cochlear nuclei- synapse site of vestibulochlear nerve

Front 90

fxn

Back 90

Trapezoid body-Projection from cochlear nuclei to superior olivary nucleus

Front 91

fxn

Back 91

Superior olivary nucleus- receives from trapezoid body, projects as lateral lemniscus to inferior colliculus

Front 92

fxn

Back 92

Inferior colliculus- receives info from lateral leminiscusand projects ot medial geniculate nucleueus of the thymus

Front 93

fxn

Back 93

Medial geniculate nucleus of the thalamus -Receives input from inferior colliculus and sends it to A1