Vesibular system Flashcards
role of the vestibular system
controls posture and balance
what are the fulid filled memnaous tubes called in the vestibular systme
labyrinths - made out of bones
what makes up the vesibular system
3 seniciruclar canals
utricle and saccule
what do the semi ciruclar canals connect to
the utricle
what direction are the semiciurlation cannals to each other
90 degrees
otolith organs are the
utricel and saccule
funciton of otolith organs
acelleartion in vertilcle and horizontal planes
what direction deos the utricle meansure in
front / back tilit and horotial acellation
what direction does semiculr canlas meausre
acceleration in the rotational plane
what are the apulla
location of the sensory cells in the semiciruclar canals, this is at the base of the canals and feaurs a swelling
cupula
hairs of te sneosry recprots are embedded in the cuprula which stretches across
what neve is the ampulla conencted to
vestibular nerve - cn8
does hte endolymph move with rodation
not intially due to inertia
why does the amilla move and not the endolyn
it is attahced to the base of the skull, thus is indepned on enodplymp
why when you sudnely stop do you feel dizzy
as endollymph is still moving but the ampula suddenly stops
what are the types of cilia, large and small
large - kinocilum
small sterocilia
what happens with distoriation of the cilia in the direction of the kioclium
cuase depolatio and increase dishcae aps win the veislular derve
wha thappesn when the cilia move away from the kinocilmum
moves to hyperpolation and reduces aps
what is the sensory appautars of the utriucle and sacculae
macule
what directio are teh macula oriated in
in utrilce - horizona
in saccule - verticle
how many kinoclium are in the maculae
1
how many steroclium anre in the macule
many
what type of caco3 cystail is in te maculae
otoliths
why is otoliths used insead of endolyn in mcuale
it is heavier, thus more effected by graivty
what is te otolyh memane made out of
otolith crystals
what are the name for te type of mass on othlih
gelatinous mass
what informati goes to the vesiuar neuli in the brain stme
propiercioan in limbs, trunk, head and neck, and otlith organs
what is the effect of teh information entering the vesitlar nuclie in the brain stem
goes to extraocular nucli,
cerebal cortesx, kinestheisa
goes to descenign spinal cord motor pathways
cerebellar centres
what is the types of vesibular system reflexes
tonic labyrithine reflexes
dynamic righting reflexes
vestibulo ocular reflexues
what is the tonic labyrithine relfex
where the axis of te head is in a constant relationship with the rest of te body
what sensory help hte tonic labyrthine relfex
maculae and neck propicoptors
what is the dynamic righting reflex
where ther is rpaid posturla reflexes to stop you falling
what happens in dynaic righting relexes
extenion of all limbs
what is the vesibulo occular reflex
connects vesiular appartus and vesiblar apartus for postural contol
what crail nerves can be triggerd by the vesibular system
3, 4 and 6 for eye movement
what is vesibular nystagmus
where the head roates agist te moevment so you stay looking at the same way you originally were
what is preventing the eyes overroating
bony orbit and full extion of muscles
what happesn when eyes overroatin in vesibuar nystagmus
flick back rapidly to the original position
what direction of flip back is right nystagmus
the eye rapidly flicks back to the right, thus making it be called right nystagmus
what is caroric stimulation
where the outer ear is washed with cold or warm fluid, to cause nystagmus
which side is the nystagmus if the fluid si warm
to the effected side
which side is te nystam to if the fluid is cold
opposite side
cows
cold opposite, warm same side
what is the effect of a lesion to periphal or central vesnibular pathways
nystagmus
cuase of motion sickens
mismatch in cerbellum with vesibular stystem and vestibular system
what is labyrinthistis
acute interferio with normal vesibular funciotn due to infection
what is the symtoms of labyrinthis
ans symtons and vertilce
what is vertiog
where you think ther is movement in the absence of movement
what is cuase of menieres diesea
over producito of endylyph incres pressure in ear
can lesion of brian cuase nystagmus
yes
