Week 5.1 Postural Control Flashcards
postural control
controlling the bodies position in space for stability and orientation
postural orientation
ability to maintain appropriate relationship between body segments and between the body and the environment
postural stability
ability to control the COM in relation to the BOS
what two things make up postural control
stability and orientation
what is the COM
point at the center of the total body mass
COG
vertical projection of the COM
BOS:
area of the body that is in contact with the supporting surface
COP
the center of the distribution of the total force applied to the supporting surface.
all tasks require _____- so every task has what two components
postural control
stability
orientation
PC is the interaction between what 3 things
task, individual enviro
what 3 pieces fit into the individual part
motor
sensory
cognition
how does motor relate to PC
MSK and muscle synergies
how does sensory fit in with PC
your sensory system and the organization
how does cognition fit in with PC
strategies, responses, resources, attention, motivation and intent, and also the ability to adapt to a changing situation based on past experiences
what three things in the environment affect PC
support surfaces
sensory context
cognitive load (multiple tasks at once)
attention for postural tasks may do what to a second task
reduce performance of a second task
complex secondary tasks can ________ of concurrently performed postural tasks
reduce performance
can attention in some secondary tasks improve PC
yes, but how
steady state
ability to keep COM in the BOS in non changing conditions
proactive
anticipatory and feedforward, activating muscles to keep balance when displaced.
reactive:
ability to recover when a perturbation happens
how does body alignment contribute to PC
minimizes gravity when you are stacked on your bones and joint.
muscle tone and contribution to PC
allows the body from collapsing due to the forces of gravity
postural tone and PC
keeps body from collapsing
when might someone use an ankle strategy
firm surface, small perturbations
when might someone use a hip strategy
on a smaller, more pliable surface with a larger and faster perturbation
what are the two changing in support recoveries of balance
step
reach to grasp
what is stepping
when there is rapid movement, and you put your foot under the falling COM
what always precedes a stepping change in support
a M/L anticipatory postural adjustment
how does the CNS prevent instability
activates synergistic muscles at mechanically related joints
what are the postural contributions for controlling postural orientation and stability
tonically active extensor muscles, antigravity muscles, for support in orientation
what is the brainstem contribution to postural orientation and stability
the brainstem controls the level of postural control, vestibular and autonomic synergies
what is the contribution of the BG and cerebellum to postural orientation and stability
BG: postural set (ability to quickly change muscle patters)
Cerebellum: control of adaptation, and the ability to modify postural muscle amplitude
