Topic 5 - vestibular system Flashcards
what is the body’s equilibrium
state of balance of the body through a variety of sensory inputs and postural reflexes (maintain posture)
done through various sensory inputs
main = inner ear
what is the primary sensory input for equilibrium
gravitational forces
what is the differnces between static and kinetic gravitational forces
static = when the body is standing still
kinetic = when the body is in motion and may occur in a straight line (linear) or in an angular direction (curvilinear)
what is the relationship between BOS and COP to maintain balance
COP must stay within BOS to remain balanced (more central = more stable)
- some sports push the boundary of this (gymnasts/dancers)
- different sports have different dynamic patterns of postural sway
what does the membranous (otic) labyrinth detect
linear motion and gravitational force
what is the membranous labyrinth composed of
sacs and ducts within the bony cavities
utricle and saccule
othliths on top of otholithic membrane
what are maculae receptors for
static equilibrium
- transduce translational (linear) accelerations acting on the head
what is the bony (periotic) labyrinth composed of
interconnected cavities within the temporal bone
semicircular canals
what do the semicircular canals detect
rotational acceleration/deceleration
what are the semi circular canals composed of
2 vertical canals
1 horizontal canal
- contain endolymph
- end with enlarged area where it opens into the utriculus (ampulla)
- on each ampulla wall = hair cells (cupula)
what is the function of endolymph
as endolymph moves, it bends the hair cells in directional response to the kinetic gravitational forces initiated by head mvmt
where are nerve impulses from the vestibular system transmitted and processed
vestibular nucleus (brainstem) and cerebellum
forces in concussion can also be transmitted to the brainstem
what does the vestibular nuclei receive / do
receive input from eyes and somatic proprioceptors
coordinates info to help control motion of eyes, neck, and limbs
what does the cerebellum receive / do
receives input from eyes and somatic proprioceptors
coordinates info to help regulate head position, posture, and balance
