ANAT vestibular system Flashcards
5 components of the vestibular system
peripheral receptor apparatus central vestibular nuclei vestibuloocular network vestibulospinal network vestibulothalamocortical network
which component of the vestibular labyrinth houses the vestibular receptors
membranous labyrinth
what type of movement do the semicircular canals detect
rotational head movements
what type of movement do the otolith organs detect
translational head movements (linear acceleration)
blood supply to labyrinth
labyrinthine a (branch off AICA) stylomastoid a
Meniere’s disease
disruption of normal endolymph volume resulting in endolymphatic hydrops
what is a kinocilium
longer stereocilia
type 1 vs type 2 hair cells
type 1: chalice-shaped, surrounded by an afferent
terminal; medial
type 2: cylindrical, innervated by synaptic boutons;
lateral
both receive synapses from vestibular efferents that control receptor sensitivity
activated by behaviorally arousing stimuli or CN V
what does the vestibuloocular network do
permits keeping a fixed gaze on an object while the head is moving
what is vestibuloocular reflex
stabilizing eye movements
helps vestibuloocular network do its thing
what detects vertical movements
vestibuloocular reflex
vertical semicircular canals and saccule
what detects horizontal movements
vestibuloocular reflex
horizontal canals and utricle
what detects torsional eye movements
vestibuloocular reflex
vertical semicircular canals and utricle
Caloric test
induces nystagmus
COWS
area 2v
vestibular cortex
located on primary somatosensory cortex
sensations of whole body motion
area 3a
vestibular cortex
located on primary somatosensory cortex
integrates motor control of head and body
area 7
lesion?
(vestibular cortex)
located on parietal cortex
integrates cues of body motion in space
lesion - confusion in spacial awareness
subjective vertigo
pt experiences sensations of spinning while things in environment are not moving
objective vertigo
sensation is one of objects spinning while patient is not moving
benign paroxysmal positional vertigo
brief episodes of vertigo that coincide with changes in body position
otoconial crystals from utricle separate from the otolith membrane and become lodged in the cupula of a semicircular canal (cupulolithiasis)
vestibular schwannoma
benign tumor
typically in cerebellopontine angle where it can impinge on CN VII, VIII, labyrinthine a
vestibular neuritis
edema of vestibular nerve (or ganglion)?
