Balance - Class 7 Flashcards
balance
dynamic process by which the body’s position is maintained in equilibrium
equilibrium
body is either at rest (static)
or
in steady state motion (dynamic)
when is balance highest
when COM or COG is maintained over its base of support
COM
direct center of total body mass
determined by weighted average of COM of all body segments
COG
vertical projection of the center of mass to the ground
where is COG typically located
slightly anterior to S2
BOS
perimeter of the contact area b/w the body and its support surface
limits of stability
sway boundaries someone can move their center of mass
before needing to move their center of mass
center of pressure
location of the vertical projection of the ground reaction force
what can balance control be influenced by
nervous system
MS system
contextual effects
nervous system
sensory processing
sensorimotor integration
motor strategies
sensory processing
for perception of body orientation in space
sensorimotor integration
essential for linking sensations to motor repsonses
motor strategies
for planning
programming
executing balance response
MS system
postural alignment
flexibility
joint integrity
muscle performance
sensation
contextual effects
open v. closed environment
support surface
amount of lighting
effect of gravity and inertia
nature of task
what does the largest influence on balance come from
somatosensory
vestibular
visual sensations
somatosensory includes
proprioceptors
joint receptors
skin mechanoreceptors
when is reliance on somatosensory required
support surface is moving or no horizontal
vestibular system involves
semicircular canals
otoliths
what is the vestibular system responsible for
sensation of position and movement of the head with respect to gravity and inertia
visual
position of the head relative to the environment
orientation of the head to maintain stable gaze
direction and speed of head movements
the vestibular, somatosensory and visual systems are
seamlessly integrated to maintain control of balance
where is info processed
cerebellum
BG
supplemental motor cortex
which system is processed the fastest
somatosensory
visual and vestibular follow
what happens when info from one system is inaccurate
CNS suppresses and select and coordinate info form other systems
when is manipulation of these systems considered useful
when working on improving balance w/ sensory impairments to any of the three areas
