Theories of Motor Control Flashcards
Reflex theory assumptions:
- Reflex is the basic unit of behavior
- Complex movements are produced by summation of reflexes
- Sensory input drives, and is necessary for, normal mvmt behavior
Reflex theory limitations
- We can override the reflex activity (saving a child from a fire)
- Fast movements - not enough time to process sequential sensory feedback
- Spontaneous & voluntary mvmt are possible without sensory input
- A single stimulus can result in a variety of responses depending on context
- Can’t explain how new mvmt are produced
Hierarchical Theory of motor control assumptions:
- CNS organized from top down
- To perform voluntary mvmt higher center must inhibit lower-level reflexes
- Development of mvmt in infants parallels “corticalization” of CNS
- Pathology of higher reflexes = release of primitive reflexes from inhibition
Hierarchical Theory of motor control limitations:
- Lower reflexes prevail in certain situation (withdraw reflex when finger is burned)
- Does not explain how voluntary mvmt are controlled
- Does not explain “bottom-up” control within the CNS.
Motor programming theory of MC assumptions:
- Motor programs control motor actions
- Mvmt can controlled by sensory input or central processes
- Generalized motor programs stores general rules for mvmt, but timing and force production can vary.
Motor programming theory of MC limitations:
- Focuses enterily on CNS initiation and control of mvmt, no reflexes integration
- Does not explain how the context or environment impact mvmt and its control
- Variability in mvmt is seen as error
This theory of motor control approach supports importance of helping patient relearn proper rules for movement and it focuses intervention on relearning functional
movements vs reeducation of specific muscles
Motor programing theory of motor control
Systems Theory (Bernstein) assumptions:
- Considers how the body as a WHOLE responds to CNS commands
- Movement emerges from the interplay between CNS commands, the mechanics of the body, and external forces like gravity
- Distributed model of control
- Synergies
Bernstein looked at the whole body as a mechanical system, with mass, and subject to both….
external forces** such as gravity and **internal forces such as both inertial and movement-dependent forces.
Wich theory of motor control suggest that optimal variability provides for flexible, adaptive strategies, allowing adjustment to environmental change, and as such is a central feature of normal movement.
Systems Theory of motor control
(AKA dynamic systems theory)
Ecological theory of motor control, assumptions:
- Actions require perceptual information that is specific to a desired goal-directed action performed within a specific environment.
This theory of motor control suggests that motor control evolved so that animals could cope with the environment around them, moving in it effectively in order to find food, run away from predators, build shelter, and even play
Ecological theory of motor control
Ecological theory of motor control, limitations:
- gives less emphasis to the organization and function of the nervous system that led to this interaction.
Task oriented approach assumptions:
- Normal movement emerges as an interaction among many different systems, each contributing different aspects of control.
- Movement is organized around a behavioral goal and is constrained by the environment.
- Emphasizes role of behavioral goals in organizing solutions to movement tasks
Task-Oriented Approach limitations:
- Difficult to know which system to start with
- Balance between “ideal” patterns and self-generated, but inefficient or risky, movement solutions not clear.
- Little guidance about when to treat impairments vs. when to focus on improving functional behaviors or participation issues
