Vestibular Terms Flashcards
Otoliths
detects translation movements: up and down, left and right, forward and backward.
Semicircular Canals
detect rotational movements: forward, backward, Horizontal.
Saccule
detects translational movement in the left-right and up-down directions.
Utricle
detects translational movement in the forward-back and up-down directions.
Posterior
detects backward rotation of the head, and its plane is offset by 45 degrees from vertical.
Anterior
detects forward rotation of the head, and its plane is offset by 45 degrees from vertical.
Horizontal
detects horizontal rotation of the head, and its plane is offset by 30 degrees from horizontal.
Cochlea
detects sound
Vestibulocochlear
carries sensory information regarding head position and movement, and sound, into the pontomedullary junction of the CNS in the brainstem.
Vestibular Nuclei
responsible for processing vestibular sensory information, and receiving sensory input to aide in executing balance reactions.
Stereocilia
converts the movements of the head into action potential firing rates, which travel up CN VIII.
Cupula
pliable barrier within the base of each semicircular canal with hair cells embedded within it, so that when the head rotates, this structure moves, bends the hair cells, and influences action potential firing rates
Endolymph
fluid which pushes against the sensory organs to result in the detection of head movement
Perilymph
fluid between the bony labyrinth and the membranous labyrinth of the vestibulo-cochlear apparatus
Otoconia
calcium crystals found in the vestibule, where they attach to saccules and utricles to aide in the detection of translatory head movements
