Motor Control Flashcards
movement emerges from interaction of what 3 factors?
individual
task
environment
examples of closed loop control movements
driving, painting, eating, actions that are continuous or slow enough to recieve input and make corrections
examples of open loop control movements-
serving a volleyball, golf swing, righting urself after slipping on ice. Happens to fast to adjust during the action, so u have preprogrammed movement srategies u rely on and u evaluate how it went afterwards
parameters of a generalized motor program?
duration of movement
overall force that will be required
selection of mm to complete the movement
in perception and object recognition (conscious identification of objects), where does the visual path go?
Ventral stream pathway: visual cortex to temporal cortex
in localization based on vision, how does the path go?
Dorsal stream pathway: visual cortex to parietal lobe
cutaneous afferent fibers and mm spindles are important for what part of reaching?
hand/arm position
what controls grip force?
cut. afferent fibers
what cortex is critical for grasp control?
somatosensory cortex
visual and somatosensory control allow for correct what?
initial direction of reach
what does each part of the brain do for reach and grasp? motor cortex cerebellum midbrain brainstem
MC: normal movement pattern, more imp. for precision grip, not power
Cerebellum: coordination of reach and grasp and anticipatory postural control
midbrain and brainstem: proximal mm in reach
need 4 things for reach
1 appropriate mm tone
2 ROM in hand, arm, trunk
3 mm strength
4 synergistsic control of components of movement
2 requirements for successful grasp
- hand must be adapted to shape,size and use of object
- finger movements must be timed in relation to transport
when does hand shaping begin?
during transport phase of gait
4 phases for lift
1) contact object
2) grip force and load force on fingers increase
3) load force overcomes wt. of object and it moves
4) end of lift- decrease in grip and load after object makes contact with surface
what happens when a person with hemiplegia performs bimanual tasks? (both hands at same time)
both hands go at the speed of the bad arm.
what happens to grip as we age?
less ability to appropriately estimate grip force needed, more hand unsteadiness, slower reach times, etc.
differentiate COM, COP, COG
COM: center of total body of mass
COP: center of distribution of total force applied to the supporting surface
COG: vertical projection of the COM.
ankle strategies
small perturbations
hip strategies
larger perturbations
stepping strategy
largest perturbations
mm activation with small backward movement of platform (ankle strategy)
person leans fwd
gastrocs first
hamstrings
paraspinals
mm activation with small forward movement of the platform( ankle strategy)
person leans backward
tibialis anterior
quads
abdominals
mm activation with LARGE backward movement of platform (hip strategy)
person bends fwd at waist
abs first
quads
paraspinals (to bring back up to neutral)
mm activation with LARGE fwd movement of platform (hip strategy)
person arches back
paraspinals
hamstrings
abs (to bring back up to neutral)
what sensory information is highly valued during quiet stance, but is not critical during perturbed stance?
vision
mm ______ is more highly correlated to physical function than mm _______
power, strength
spontaneous sway ________ with each decade of life
increases
older adults have greater use of what strategies for balance
hip, skip ankle and go straight to hip!
which sensory system is most valuable to older adults for balance?
vision, but mostly its a matter of more than one system being unavailable for consultation that causes the most problems.
type of attention also known as vigilance
sustained attention- focus on one task for long periods of time
switching attention
switching focus from one thing to another and then back again, not same as doing two things at once, ex of switching attention is when I was painting my spoons for the craft day and then carson wanted me to tie his shoe.
card test used in clinics to measure attention switching
Wisconsin Card sorting task
selective attention
ability to focus on the relative information in the presence of distractors
test for measuring selective attention
Stroop Task
read the words aloud as fast as u can, the words are Red, Green, Yellow, first is congruent so the word Red is colored red etc, the next time its incongruent so the word Red is colored yellow and etc.
divided attention
doing two things at once
3 essential aspects of successful locomotion
progression
postural control
adaptation
10 m walk measures what about gait?
velocity
stride length
distance from one heel strike with R foot to second heel strike with R foot
average walking speed for healthy adults
1.46 m/sec or 3.26 mi/hr
mean step length
76.3 cm (30 in)
mean cadence
1.9 steps /sec (112.5 steps/min)
recovery from LOB takes place in a _____ to _____ sequence
distal to proximal
first movement of COP when initiating gait is in what direction?
posterior to lateral toward swing limb
transition to running reduces stress on …
DFs
what accounts for largest number of public falls
stair descent
when is greatest instability during stair climbing?
with contralateral toe-off when the ipsilateral leg takes all the body’s weight and the limb is flexed (takes 2x as much force than level gait) Foot clearance and placement are also crucial- Vision is crucial!
4 phases of sit>stand
1) wt. shift or flexion momentum: flexion of the trunk,
2) beginning of lift: buttocks leave seat, most unstable phase!
3) lift/extension: extension of the hips and knees
4) stabilization: body stability is achieved
3 strategies for sit>stand
1) momentum transfer strategy: 4 phases
2) zero-momentum strategy: flexing trunk to put COM over feet, more stable but need greater force from LEs.
3) armrests: assists in stability and force generation, however, not always an option
