A&P Review Flashcards
role of peripheral and central vestibular systems
estimates body position/movement
postural control
control eye movement
autonomic function and consciousness
project information throughout our cortex, brainstem and cerebellum
pitch
flexion / extension
yaw
rotation
roll
lateral flexion
peripheral 3 primary functions
- stabilize visual images on the fovea of the retina during head movement allow for clear vision
- maintain postural instability, especially during movement of head
- provide information for spatial orientation
the vestibular labyrinth contains what
bony and membranous labyrinth
bony labyrinth contains what and what is it
perilymphatic fluid + supportive connective tissue
suspension system that keeps away from the bone
how does the bony labyrinth communicate with CSF
via cochlear aqueduct
what does the membranous labyrinth contain
endolymph fluid, vestibule, 3 semicircular canals
what is the vestibule
otolith organs: utricle and saccule
the otolith organs relay info how
linear acceleration/deceleration of head/neck & static head position
utricle detects movement in the ____ plane
horizontal
saccule detects movement in the _____ plane
vertical
stereocilia/hair cells motion receptors do what
transduce minute displacements into behaviorally relevant potentials
movement of stereocilia towards kinocilium:
excitatory
movement of stereocilia away from kinocilium:
inhibitatory
what is the layer on top of the macula
otoconia
what is the otoconia
calcium carbonate crystals
heavier
why are the otoconia heavier
help exaggerate gravitational pull to excite/inhibit easier
utricle: stereocilia located on the ___ of the organ, kinocilium position towards ____
floor
midline
saccule: stereocilia located on ___ of organ, kinocilium positioned towards ____
medial wall
lateral
ampulla is what
bulbous formation at the start or finish of each canal
what does the ampulla contain
cupula which houses stereocilia
not gravity dependent
endolymph moves in opposite direction
NO kinocilium
direction of hair cell displacement in relation to the _____ dictates the type of polarized response elicited
utricle
TOWARDS utricle
utriculopedal cupular displacement
AWAY from utricle
utriculofugal cupular displacmeent
utriculopedal cupular displacement is ___ for the horizontal canal and _____ for the anterior/posterior canal
excitatory
inhibitory
utriculofugal cupular displacement is ___ for the anterior/posterior canal and _____ for the horizontal canal
excitatory
inhibitory
what artery supplies the vestibular labyrinth
labyrinthine artery
what supplies the vestibular nerve, utricle, ampullae of anterior and horizontal SCC
anterior vestibular artery
what supplies the cochlea, ampulla of posterior SCC, saccule
common cochlear artery
generates eye movements that enable clear vision while head is in motion
vestibulo-ocular reflex VOR
generates compensatory body movement to maintain head and postural stability
vestibulospinal reflex VSR
acts on neck musculature to stabilize the head
vestibulocollic reflex VCR
interacts closely with VOR
eye movements driven by neck proprioceptors
cervico-ocular reflex COR
changes in limb position driven by neck afferent activity
can supplement VSR
cervicospinal reflex CSR
helps stabilize head on body
afferent input caused by changes in neck position –> contrlateral reflexive contraction of appropriate neck muscles
cervicocollic reflex CCR
which nuclei is the principle vestibular relay
lateral nucleus
which nuclei does VOR and VSR relay
medial nucleus
which nuclei does VOR relay
superior nucleus
which nuclei does cerebellar and reticular formation relay
inferior nucleus
which vestibulospinal tracts travels to the thoracic spinal cord to extensor musculature?
head/body position in space
walking upright
righting and equilibrium reactions
lateral vestibulospinal tract
which vestibulospinal tract travels to the cervical spinal cord to extensor musculature?
head movements
integrating head/eye movements
medial vestibulospinal tract
VOR/VSR suppression does what
flocculonodular node leads to inhibitory drive to VOR/VSR
vestibulocerebellar tract does what
intended vs actual movement/error correcting mechanism
vestibular nuclei to flocculonodular node
what does the cerebellar-cortical loop do
adaptation of postural responses based on prior experiences
central integrative data
flocculonodular node to vestibular cortex
