20 (pt 2) Auditory and Vestibular System

Question 1

external ear

Answer 1

pinna
auditory canal

Question 2

middle ear

Answer 2

tympanic membrane
ossicles
oval window
muscles

Question 3

what separates the outer ear and inner ear

Answer 3

tympanic membrane

Question 4

ossicles

Answer 4

malleus, incus, and stapes transfer movement of the tympanic membrane to movement of the oval window

important for sound force amplificaton

Question 5

oval window

Answer 5

membrane covering a hole in the skull that transmits vibrations to the cochlea

Question 6

foot plate

Answer 6

the bottom part of the stapes that is connected to the oval window

movement of footplate moves oval window

Question 7

two parts of inner ear

Answer 7

auditory apparatus: cochlea

vestibular apparatus: semicircular canals, utricle, saccule

Question 8

3 fluid filled chambers of the cochlea

Answer 8

scala vestibuli
scala media
scala tympani

Question 9

organ of corti

Answer 9

part of the cochlea that contains the auditory receptor cells → initiate mechanoelectrical transduction

Question 10

basilar membrane

Answer 10

vibrates in response to sound

Question 11

mechanoelectrical transduction

Answer 11

sound wave hits tympanic membrane → ossicles move, causing vibration of membrane at opening of cochlea → fluid in cochlea moves → basilar membrane and embedded hair cells to vibrate → hair cells bend against tectorial membrane → hair cells depolarize → cochlear nerve endings activated

Question 12

location of auditory cortex

Answer 12

temporal lobe

Question 13

brainstem auditory center

Answer 13

cochlear nuclei: medulla
superior olive: pons
lateral lemniscus: pons
inferior colliculi: midbrain

Question 14

superior olive function

Answer 14

sound localization

Question 15

lateral leminiscus function

Answer 15

transmits sound information from the cochlear nuclei to inferior colliculus.

Question 16

inferior colliculus function

Answer 16

processes sound frequencies
sound localization

Question 17

superior colliculus functon

Answer 17

orients eyes and head toward direction of sound

Question 18

primary auditory cortex

Answer 18

determines intensity of sounds

Question 19

secondary auditory cortex

Answer 19

classifies sounds

memories of sounds

Question 20

peripheral vestibular system

Answer 20

semicircular canals
otoliths

Question 21

semicircular canals

Answer 21

rotational acceleration

anterior: flex/ext
posterior: side bending
horizontal: rotation

Question 22

otoliths

Answer 22

linear acceleration

utricle: horizontal movements
saccule: vertical movements

Question 23

ampulla vs. cupulla

Answer 23

ampulla: base of semicircular canal

cupula: is a gelatinous structure that sits on top of the crista inside the ampulla.

Question 24

crista

Answer 24

sensory organ in the ampulla

Question 25

macula

Answer 25

specialized sensory regions in the otolith organs which are responsible for detecting linear acceleration and head position relative to gravity. | synonymous to cupulla of SCC

Question 26

semicircular canal functional pairs

Answer 26

R/L horizontal SCCs R anterior/L posterior SCCs R posterior/L anterior SCCs

Question 27

otoconia

Answer 27

calcium carbonate crystals in the macula that move on top of the gel later to bend the hair cells

Question 28

info is converted to neural signals to the vestibular nerve to which lobe of the cerebellum

Answer 28

vestibulocerebellum (flocculonodular lobe)

Question 29

central vestibular system

Answer 29

vestibular nuclei 6 pathways vestibulocerebellum vestibular cortex

Question 30

descending vestibular pathways

Answer 30

vestibulospinal tracts vestibuloreticular pathway vestibulocolic pathway

Question 31

medial vestibulospinal tract

Answer 31

Head/neck stabilization via neck muscles - vestibulo-cervical reflex

Question 32

vestibulo-cervical reflex

Answer 32

postural adjustments of head in response to activation of SCCs

Question 33

lateral vestibulospinal tract

Answer 33

postural control via extensor muscles -vestibulo-spinal reflex

Question 34

vestibulo-spinal reflex

Answer 34

postural and tone adjustments of body

Question 35

vestibulocolic pathway

Answer 35

goes to CN XI nucleus to affect cervical muscles' postural control

Question 36

what results from disrupted descending pathways

Answer 36

balance deficits which impacts movement abilities/control

Question 37

ascending vestibular pathways

Answer 37

vestibulothalamocortical pathway vestibulocerebellar pathways medial longitudinal fasciculus

Question 38

where do ascending vestibular pathways start?

Answer 38

vestibular nuclei

Question 39

vestibulothalamocortical pathway

Answer 39

Vestibular nuclei → Thalamus → Vestibular cortex (posterior parietal cortex) Perception of balance, spatial orientation

Question 40

vestibulocerebellar pathways

Question 41

medial longitudinal fasciculus

Answer 41

vestibular nuclei → CN III, IV, VI mediates VOR → influences eye and head movements