27-Motor8-Vestibular Flashcards
(40 cards)
Signals from vestibular apparatus leave in cranial nerve ___:___
VIII, vestibulocochlear
Three compartments of vestibular system
- bony labyrinth
- membranous labryinth
- endolymph
Vestibule is part of the [bony/membranous] labyrinth
bony
Semicircular canals are part of the [bony/membranous] labyrinth
bony
Saccule is part of the [bony/membranous] labyrinth
membranous
Utricle is part of the [bony/membranous] labyrinth
membranous
Semicircular ducts are part of the [bony/membranous] labyrinth
membranous
Fluid inside membranous labyrinth
endolymph
___ sense head rotation
Semicircular ducts
___ sense gravity and linear head motion
Otolithic organs
Otolothic organs include ___ and ___
saccule and utricle
Primary vestibular afferents terminate in ___
vestibular nuclei
Vestibular nuclei integrate inputs from vestibular system with other inputs from (x3)
spinal cord, cerebellum, and visual system
Vestibular nuclei project to ___ (x4)
motor structures:
- oculomotor nuclei (oculomotor reflexes)
- reticular system, spinal cord (skeletal reflexes)
- cerebellum (motor coordination, balance)
- thalamus (motor control, position sense)
Primary afferents from semicircular ducts terminate primarily in ___ vestibular nuclei
superior and medial
Primary afferents from otolithic organs terminate primarily in ___ vestibular nuclei
lateral
Information from semicircular ducts primarily affects reflexes that involve ___
gaze
Information from otolothic organs primarily affects reflexes that involve ___
anti-gravity (e.g. posture)
Function of vestibulocollic reflex
stabilize head position
Hair cells:
Deflection toward kinocilium produces [depolarization/hyperpolarization]
ON direction, depolarization
Hair cells:
Deflection away from kinocilium produces [depolarization/hyperpolarization]
OFF direction, hyperpolarization
true
Hair cells in ampulla are embedded in ___
christa = a ridge of epithelium
true
