Intro to motor control and theories

Question 1

The ability to regulate or direct the mechanisms essential to movement

Answer 1

motor control

Question 2

Why do PTs study motor control?

Answer 2

It will help our interventions be more effective

- Understanding the control of movement already acquired

Question 3

How does movement emerge?

Answer 3

an Individual completing a Task in a given Environment

- organized around both tasks and environmental demand

Question 4

Integration of sensory impressions into psychologically meaningful information

Answer 4

perception

• results from influences of the PNS and CNS
• perception can change movement or action

Question 5

what are the individual movement constraints in cognition/intention?

Answer 5

1. Attention
2. Planning
3. Problem Solving
4. Motivation
5. Emotion

Question 6

What are the task constraints of a movement?

Answer 6

1. Mobility (moving BOS)
2. Stability (static BOS)
3. Manipulation (UE only)

Question 7

How do you classify task constraints on movement?

Answer 7

1. functional
2. Critical attributes (discrete vs. continuous)
3. Base of support (stable vs mobile)

Question 8

What are they types of environmental constraints on movement?

Answer 8

1. regulatory

2. non regulatory

Question 9

environmental contrstraint that affects movement itself

Answer 9

regulatory features

• adding a 5 lb ankle weight in a long arc quad
• task-specific movements must conform to regulatory features of the environment in order to achieve the goal of the task

Question 10

environmental contrstraint that may affect performance but the specific movement isn’t affected

Answer 10

non-regulatory

• walking to the bathroom at night in the dark
• background noise
• presence of distractions

Question 11

Set of interconnected statements that describe unobservable structures or processes and relate them to each other and to observable events; Reflection of different philosophical views about how the brain controls movement

Answer 11

theories of motor control

Question 12

What are the theories of motor control?

Answer 12

1. Reflex
2. Hierarchical
3. Motor Programming
4. Systems
5. Ecological

Question 13

Theory states reflexes are the building blocks of complex behavior; Explain stereotyped movement

Answer 13

reflex theory

Question 14

What are the limitations to reflex theory?

Answer 14

1. fails to explain how spontaneous and voluntary movement occurs
2. Movement without sensory stimulus
3. Fast movement (i.e., playing piano)
4. Single stimulus produces, varied response
5. Doesn’t explain how novel movements occur

Question 15

What are the clinical implications of reflex theory?

Answer 15

1. Predict function - reemergence of primitive reflexes can indicate neurological damage
2. Interpretation of movement behavior
3. Limited rehabilitative focus

Question 16

theory is based on the top down organization of the nervous system; strictly vertical - lines of control do not cross, never bottom-up

Answer 16

hierarchical theory

- each successively higher level exerts control over the level below it

Question 17

What are the limitations to hierarchical theory?

Answer 17

1. Doesn’t explain reflexive behavior in typical adults (pulling hand away from hot stove)
2. makes the assumption that low-level behaviors are primitive, immature, and non-adaptive, while high-level behaviors are always mature, adaptive, and appropriate

Question 18

What are the clinical implications of hierarchical theory?

Answer 18

Assist in explaining disordered motor control in light of a neurologic injury (integrated reflexes reemerge when higher centers are damaged)

Question 19

Theory that looks at the progression from physiology of reactions (reflexes) to physiology of action; CPGs; explains higher level motor programs that represent actions in abstract terms

Answer 19

Motor programming theory

- walking

Question 20

neural connections that are hardwired or stereotyped; innate motor patterns that don’t require cortex control

Answer 20

central pattern generator (CPG)

Question 21

What are the limitations to motor program theory?

Answer 21

• Not intended to undermine the role of sensory input (sensory info modulates the frequency of pattern)
• Expanded understanding of increased flexibility of nervous system
  1. CPG: Not the sole determinant of a movement
  2. Lacks consideration for: musculoskeletal system and how environmental factors impact movement

Question 22

What are the clinical implications of motor program theory?

Answer 22

• move beyond a reflex explanation for disordered motor control
• explanations for abnormal movement have been expanded to include problems resulting from abnormalities in CPGs or high level motor programs
  1. Improved Understanding: CPGs in SCI, High Level Motor Programs
  2. Improved Intervention- allowing for gait training with SCIs

Question 23

theory that uses the body as a mechanical system; gives a view of the body as a whole (muscular system working with neurological system); explains why a central command may have a different resulting movement; takes into account the degrees of freedom, synergy and dynamic systems theory; higher levels of the nervous system activate lower levels, the lower levels activate synergies (groups of muscles that are constrained to act together as a unit)

Answer 23

systems theory

Question 24

Foundationally similar to systems theory; “Self-Organization”; Non-Linear; Control Parameter; Appreciates inherent variability, considered a consequence of errors in performance; Provides for flexible, adaptive strategies; Allows for adjustment to environmental change; variability will increased prior to emergence of new, more stable patterns of behavior

Answer 24

Dynamic systems theory

- limitation: Nervous system has a less important role in determining behavior

Question 25

What are the clinical implications of the systems theory?

Answer 25

1. takes into account importance of mechanical system; movement is not solely determined by NS output
2. Critically Examine how impairments within specific systems interact to affect movement
3. Emergent property (most stable pattern of movement takes over): Movement depends on the interaction of multiple body systems
4. Variability: A feature of normal movement; optimal variability provides for flexible, adaptive strategies

Question 26

Theory that evolved from the observation of animals coping within their environment; focus is on how actions are geared toward environment, moving in it effectively in order to find food, run away from predators, build shelter, and play; Actions require perceptual information that is specific to a desired goal-directed action performed within a specific environment; detecting info in the environment that will support the actions necessary to achieve a goal

Answer 26

Ecological theory

- Organization of action is specific to the task and the environment it is performed within

Question 27

what is perception?

Answer 27

an interpretation of a sensory (objective) experience

Question 28

What is the limitation of ecological theory?

Answer 28

Decreased emphasis to the organization and function of the nervous system and its role in the interaction of an individual and its environment

Question 29

What are the clinical implications of the ecological theory?

Answer 29

1. Individual has an active role in movement and in exploring the environment, thus developing multiple ways to accomplish a task
2. Patient has an active role in deciding how to move: Allows for development of multiple ways to accomplish a task; Movement is a result of the solution to a “motor problem.”

Question 30

synergies are not used by the nervous system to eliminate redundant degrees of freedom, but instead to ensure flexible and stable performance of motor tasks

Answer 30

principle of abundance

- important in systems theory

Question 31

Dynamic theory suggests that new movement emerges because of a critical change in one of the systems; this is a variable that regulates change in the behavior of the entire system

Answer 31

control parameter