Balance Flashcards
what is the vestibule
a region of the inner ear which contains the saccule and utricle , each of which contain a macula to detect linear acceleration
what does the saccule detect (relative to gravity)
vertical movement (s for sky)
what does the utricle detect
horizontal movement
what are the names of the three semicircular canals
anterior, posterior and horizontal
what are otoliths
ear stones
what is the function of the semicircular canals
detects rotational movement
rotational acceleration and deceleration
3 planes of orientation
what are the directions of rotational movements
roll pitch and yaw
what is Menieres disease
vestibular apparatus is bathed in endolymph
normally drains to venous sinus
build up causes menieres disease
(vertigo, nausea, tinnitus and hearing loss)
due to increased pressure
where does information from the vestibular apparatus go
cerebellum and brain stem
what is information from the vestibular apparatus used for
controls eye muscles
maintains an upright position
awareness of body position and acceleration
what is the caloric test
put warm water in external meatus which sets up movement in the labyrinth system
warm water mimic moving head towards irrigated ear
(COWS- cold opposite warm same)
nystagmus
in comatose patients only the slow saccade
what is the utricle in contact with
semicircular canals
what is the saccule in contact with
cochlear
where are otiliths found
gelatinous matrix
describe linear translation
hair cells project into otiliths using cilia
these provide directional information
movement of the otilith membrane from tiliting or translational movement
bends the cilia (kinocillium)
this opens up a cation channel
