KINE 406 Ch.4

The human body's numerous independent elements that produce abundant action possibilities 

Degrees of Freedom (Bernstein)

The process of organizing degrees of freedom into an efficient movement pattern to achieve a specific goal 

Coordination

Manipulation of variables within a movement to meet the demands of a given situation 

Control

A memory representation that stores information needed to perform an action

Motor program

Command center in the brain thought to make all decisions regarding movement

Motor program

A command center could not account for all variations and adjustments in skilled movement

Dynamic interaction theories

Movement results from interaction of body, environment, and skill

Dynamic interaction theories

For each movement, a separate motor program existed and was stored in memory

Early Motor Program Theories

When a specific action was required, the program was retrieved from memory and executed

Early Motor Program Theories

What is the problem with early theories?

• Storage requirements

• Production of new memories

A class of actions or movement patterns that can be modified to yield various outcomes

Generalized Motor Program

What are invariant features controlled by?

Generalized Motor Program

What are parameters controlled by?

Motor Response Schema

A rule or set of rules that provides the basis for a decision

Schema

Define the program’s execution, more flexible

Parameters

Some underlying features of a movement remain constant

Invariant features

• Sequence of actions or components

• Relative timing

• Relative force

Three possible features of invariant features

Some features of a movement are flexible and are easily modified from one performance to the next

Parameter

• Overall duration

• Overall force

• Movement direction

• Muscle selection

Four possible parameters

Develops as a result of accumulated experiences

Schema

Each movement attempt gives the learner information to guide future attempts

Schema

Limb and body position and the environmental conditions at the start of the movement

Initial conditions

Parameters of the movement execution

Responce specifications

Feedback of the movement

Sensory consequences

Obtained response related to the intended goal

Response outcome

Responsible for initiating and organizing the motor program

Recall schema

A GMP is retrieved based on initial conditions and response specifications

Recall schema

Responsible for evaluating the movement attempt

Recognition schema

An error is detected by processing sensory consequences and comparing them with the actual response outcomes

Recognition schema

Set sequence of demands without using feedback to adjust outcomes

Open-loop

Continuously monitor their output and make adjustments as necessary

Closed-loop

An approach to describing and explaining the control of coordinated movement

Dynamic systems theory

Emphasizes the role of information in the environment and the dynamic properties of the body and limbs

Dynamic systems theory

When certain conditions characterize a situation, a specific stable pattern of behavior emerges

Self-organization

Self organization goes under:

Dynamic systems theory

A behavioral steady state that represents a preferred behavioral state

Stability

Preferred state of stability in a system

Attractor

Variables that, when changed, leads to corresponding changes (e.g., phase shift) 

Control parameter

An individual constraint that holds back or slows the emergence of a motor skill 

Rate limiter

Basin with stable systems and difficult to change

Deep attractor basins

Basin that is less stable and more susceptible to change

Shallow basins

All of the factors limiting and enabling within the practice environment that influence skill acquisition and performance

Constraints

Learner searches through a range of potential movement solutions for the optimum strategy

Non-linear pedagogy

What does perceptual-motor workspace belong to?

Non-linear pedagogy

Purposeful manipulation of key constraints in an effort to acquire movement skills and decision making behaviors

Constraints-led approach

What does hands-off practitioner belong to?

Constraints-led approach

Practice context for the learner; perceptual information sources and the range of movement possibilities to discover task solutions unique to that individual

Perceptual-motor workspace

Practitioner as facilitator; dictate the correct movement response through verbal instruction

Hands-off practitioner

Responsible for the evaluation of a movement attempt

Recognition schema

How to coordinate and control the body's numerous independent elements to produce movement

Degrees of freedom problem

Define the motor program itself and is relatively fixed

Invariant features