Vestibular Flashcards
What are the roles of the vestibular system?
stabilize visual image during head movement
provide sensory information for spatial orientation
maintain postural stabillity when stationary and during movement
what is postural control
control’s the body’s position in spce for stability and orientation between body segments and the environement
what is postural stability
maintenace of the COM over the BOS
what is postural orientation
ability to maintain relationship between body segments and between body and environment for a task
What are the sesory input systems
visual
vestibular
somatosensory
What are the motor output systems
VOR- vestibulo ocular reflex
VCR- vestibulo collic reflex
VSR- vestibulo spinal reflex
what plane is the utricle
horiontal
what plane is the saccule
vertical
the urticle and saccules form…
the otolith
what do the otoconia do?
provide shear forces for hair cell deflecion
What do the otoliths do?
linear motion detection
tonic discharge
push/pull relationship
What do the semicircular canals do?
angular motion detection
tonic discharge
push/pull relationship
What does the thalamus do to contribute to postural control?
assists in discrimination between self and movement and environmental movement
multisensory integration for postural control
What does the reticular formation do to contribute to postural control?
reticulospinal tract (RST) receives inpput from all vestibular nuclei
what does the cerebellum contribute to postural controol?
interacts with LVST, MVST, RST
afferent impulse travel directly from the end organ to the cerebellum
What is the vestibular cortex
junction of parietal and insular lobe
multisensory integration of vestibular information with somatosensation and vision
What does the posterior inferior cerebellar artery (PICA) supply
the inferior vestibular nuclsupplies the inferior portion of the cerebellum