Motor Theories and Control Systems

Vocabulary practice flashcards covering theories of motor control, degrees of freedom, motor programs, dynamic systems, ecological approaches, and the OPTIMAL theory of motor learning.

Degrees of Freedom (DOF)

The number of independent components in a control system and the number of ways each component can vary.

Bernstein Problem

Also known as the Degrees of Freedom (DOF) problem; the question of how the central nervous system controls all of the body's independent movement components.

Freezing Degrees of Freedom

A technique used by beginners to accomplish a movement goal by rigidly fixing particular joints/muscles or coupling body parts so they move together.

Coordination

The patterning of head, body, and/or limb motions relative to the patterning of environmental objects and events.

Engram

The physical and biochemical changes in the brain that represent a stored memory trace, providing necessary conditions for a memory to emerge.

Open-loop Control System

A control system where movement instructions are sent from the movement control center to effectors without relying on feedback during execution.

Closed-loop Control System

A control system that sends movement instructions to effectors and utilizes continuous sensory feedback returned to the control center to make corrections.

Reflex Theories

Motor control theories developed by Sir Charles Sherrington that propose movements are generated via open-loop reflex chaining models triggered by physical events in the environment.

Hierarchical Theories

Motor control theories associated with John Hughlings Jackson asserting that all aspects of movement planning and execution are controlled by higher cortical command levels within the central nervous system.

Memory Trace

In Jack A. Adams's Closed-Loop Theory, the mechanism responsible for selecting and initiating a given plan of action.

Perceptual Trace

In Jack A. Adams's Closed-Loop Theory, the mechanism that serves as a comparator to evaluate sensory feedback against the intended movement.

Motor Program

An abstract representation of a movement plan stored in memory containing all motor commands required to execute an action without influence from peripheral feedback.

Generalized Motor Program (GMP)

A theory proposed by Richard Schmidt suggesting motor programs are general in nature and characterized by fixed invariant features and adaptable parameters.

Invariant Features

Unique characteristics defining a Generalized Motor Program (GMP) that do not vary across performances, including sequence of actions, relative timing, and relative force.

Parameters (GMP)

Modifiable features of a Generalized Motor Program (GMP) that vary between performances, including overall duration, overall force/amplitude, movement direction, and muscle selection.

Schema Theory

Richard Schmidt's theory stating that motor learning relies on developing abstract rules (schemas) derived from initial conditions, response specifications, sensory consequences, and response outcomes.

Recall Schema

In Schmidt's Schema Theory, the rule responsible for selecting the specific parameter values needed to produce a chosen movement.

Response Recognition Schema

In Schmidt's Schema Theory, the rule responsible for evaluating movement correctness by comparing sensory consequences and actual outcomes.

Bernstein's Synergies

Lower-level neural groupings of muscles and joints that change together to coordinate action and solve motor problems.

Dynamic Systems Theory (DST)

A motor control theory stating that movement patterns emerge or self-organize through dynamic interactions among individual, environmental, and task constraints.

Constraints

Limits or boundaries in Dynamic Systems Theory—categorized into individual, environmental, and task constraints—that shape the emergence of movement behaviors.

Self-Organization

A core DST concept where coordinated movement patterns form spontaneously without explicit instructions or central motor programs.

Attractor State

A stable state within a motor control system representing a preferred pattern of coordination, such as normal walking cadence.

Control Parameter

Any variable (internal or external) in Dynamic Systems Theory that, when systematically altered, can push a system into a new pattern of coordination.

Order Parameter

A collective variable used in Dynamic Systems Theory to quantify and define the state or movement pattern of a dynamic system.

Phase Shift

The transition of a dynamic system from an unstable movement state to a new, stable coordination pattern induced by changes in a control parameter.

Ecological Approach

A theory of motor control championed by James J. Gibson focusing on direct perception and the reciprocal relationship between an individual and their environment.

Affordances

Opportunities for action provided by the environment that depend on the physical capabilities and characteristics of the individual.

Perception-Action Coupling

The reciprocal, continuous link between perceiving environmental information and producing motor action.

OPTIMAL Theory

Optimizing Performance Through Intrinsic Motivation and Attention for Learning; a motor learning theory proposed by Wulf and Lewthwaite (2016) integrating motivational and attentional factors.

Enhanced Expectancies

A component of OPTIMAL theory referring to a learner's positive expectations for future performance success, closely tied to self-efficacy.

Autonomy

Providing learners with choice and control over practice conditions, which enhances motivation, effort, and motor skill retention.

External Focus of Attention

Directing a performer's attention toward environmental cues or movement outcomes rather than internal body movements.