12-2 Flashcards
postural control
controlling body position in space to maintain stability and orientation
center of mass
location where all the mass of body is concentrated
centre of gravity
vertical projection of COM to the ground
what is the reflex that stepping on a nail could cause
flexor crossed extensor
what cortical are would be activated to perceive the pain
somatosensory
what neural pathway would the sensory signal travel to get to the cortical area
spinothalamic
what afference is sensory feedback
ex affernce
center of pressure
point of application of vertical ground reaction force exerted in the body
quiet standing
not actually quiet
the human body cannot continually maintain perfect equilibrium, but it can be stabilized
when stable there s some body sway and muscle activity( do to small physiological perturbation ex heartbeat and breathing)
standing balance
a controlled rhythmic act of moving body from one place to another- involves a repeated cycle of movement
body alignment
- the amount of sway affected by body alignment
- when the body is aligned with one f gravity, energy requirements are minimized and stability maximized
- a stable posture exists if the vertical line action of the force f gravity passing through whole body
a person has a stable posture as long as the
line of action of COG is within the base of support
postural stability
requires that the COG is within the base of support
- COG is within the base of support provided by the feet
inverted pendulum
mass swing back and forth (the mass if the head)
base of support
coke can
because the cog is within the base of support that coke can will not fall over
- postural stability is ____ if the ______ is reduced
Postural Stability is decreased if the base of support is reduced
- Postural Stability is ____ if the _____is closer to the ____ of the base of support
Postural Stability is decreased if the line of the COG is closer to the edge of the base of support
- Postural Stability is ___if the height of the COM is ____
Postural Stability is decreased if the height of the COM is increased
exploratory mechanism
- tell the body where it is in space
- we sway because we want sensory feedback of where we are in space
- the person wants the center of mass to move(we want sensory information)
(COP increase)
cortical or subcortical
- use EEG to record Voluntary movement
- they correlate the EEG signal with the EMG signal (good relationship with muscle and motor cortex)
-when locked COP increase
-sub cortical b/c there is something else driving the forces
