Lecture 3 - M / info processing Flashcards
What is Motor Control?
The process by which the central nervous system determines the appropriate measures to achieve the goal of a motor skill
What is a theory?
Accurately describes a large class of behaviors.
- Makes definite predictions about the results of future observations.
What does Motor Control Theory address?
Predominantly addresses motor control from a behavioral level.
Describes and explains how the nervous system produces coordinated movement during motor skill performance in various environments.
What are the two important aspects of Motor Control Theory?
- Degrees of freedom problem.
- Coordination
What is Degrees of Freedom?
The number of independent elements in a system and the number of ways each element can act
What is the Degrees of Freedom?
The number of independent elements in a system and the number of ways each element can act.
What is Coordination in Motor Control?
Patterning of body and limb motions relative to the patterning of environmental objects and events
What are the two key points in Coordination?
Relations among joints and body segments at a specific point in time
Relation between pattern of coordination and the environment to accomplish an action
What are the two Control Systems in Motor Control?
- Open-loop system
- Closed-loop system
What is an Open-Loop System?
A system in which…
Control is independent of feedback
Feedback is produced and available but not used to control ongoing movement
Movement too quick to utilize feedback effectively
What is a Closed-Loop System?
A system in which…
Control is dependent on feedback.
Sensory feedback detects errors and updates the control center to correct movement.
When does the CNS act in an Open-Loop vs. Closed-Loop System?
Precision: High precision tasks use closed-loop; low precision use open-loop.
Learning: Not well-learned tasks use closed-loop; well-learned tasks use open-loop.
Skill Type: Continuous tasks use closed-loop; discrete tasks use open-loop.
Time: Tasks with long completion times use closed-loop; short completion times use open-loop.
A high precision task uses a ______ loop system.
closed
A well learned task uses an _______ loop system.
open
A continuous task uses a _____ loop system.
closed
A discrete task uses a _____ loop system.
open
Tasks requiring a long completion time use a ______ loop system.
closed
What are the two main Motor Control Theories?
- Motor Program-Based Theory
- Dynamical Systems Theory
What is the Motor Program-Based Theory?
Memory-based mechanism that controls coordinated movement
What is a Generalized Motor Program (GMP)?
A memory-based mechanism controlling a specific class of actions, identified by common invariant characteristics
What are Invariant Features in GMP?
(give an example)
Characteristics that do not vary across performances of a skill.
Example: Relative timing in a movement
What are Parameters in GMP?
(give an example)
Specific movement features added to invariant features to adapt to the situation
Example: Overall movement speed
What does the Dynamical Systems Theory emphasize?
The role of environmental information and mechanical properties of the body in movement control
What are the key components of Dynamical Systems Theory?
- Attractor
- Order Parameters
- Control Parameters
- Coordinative Synergies
- Perception-Action Coupling
- Affordances
What is an Attractor in Dynamical Systems Theory?
A stable state of the motor control system representing preferred coordination patterns
What is Perception-Action Coupling?
(give an example)
The linking of perception and movement control.
Example: Avoiding an obstacle while walking.
What is Affordance?
Possibilities for action defined by individual characteristics and the environment
What are the three important sensory components in Motor Control?
Touch
Vision
Proprioception
What is the role of Touch in Motor Control?
Provides information about the surrounding environment.
Influences movement accuracy, consistency, timing, and force adjustments.
What is Proprioception?
Perception of limb, body, and head movement characteristics.
What are the three primary types of proprioceptors?
- Muscle Spindles: Detect muscle fiber stretch and speed of stretch.
- Golgi Tendon Organs: Detect changes in muscle tension.
- Joint Receptors: Detect force, rotation, and joint angle changes
What research techniques are used to study Proprioception?
Deafferentation (surgical removal or alteration of sensory pathways).
Sensory neuropathy studies.
Tendon vibration studies.
How does Vision influence Motor Control?
Primary sensory input for movement
Helps with depth perception, target tracking, and spatial awareness
What are the two Visual Systems?
Ventral Stream (Vision for Perception): Identifies objects and fine analysis
Dorsal Stream (Vision for Action): Guides movement and spatial characteristics
What is the Moving Room Experiment?
Experiment where walls move but the floor does not
Infants and adults adjusted posture incorrectly based on visual input, proving visual dominance in motor control
What is Time-to-Contact (Tau)?
Optical variable that determines when to initiate movement based on object size change on the retina
How much time is required for vision-based movement corrections?
Estimated range: 100-160 milliseconds
What practical applications come from these theories?
- Sensory input is crucial for motor skill
performance - Training should begin with slow speed movements
- Practitioners should ensure clear task instructions
