Chapter 1

Question 1

Multi- Level Approach

Answer 1

Two most important bodies of knowledge for motor behavior are Neurophysiology and Psychology

Question 2

Motor Behavior (3)

Answer 2

Motor control
Motor learning
Motor development

Question 3

Motor Control

Answer 3

Snapshot
What your body is capable of doing right now
When you’re standing how your body is capable to do that exact muscle contraction

Question 4

Motor Learning

Answer 4

Effects of practice

How the control of the movements change with practice

Question 5

Motor Development

Answer 5

Long periods of time

How movement skills change over long periods of time (toddler v. elderly)

Question 6

Intro to Motor Control

Answer 6

In order to understand the nature of motor control, it is necessary to discover what is actually being controlled and how the various processes of governing that control are organized

Question 7

What is Motor Control?

Answer 7

Motor control is the study of postures and movements and the mechanisms which underlie them

Question 8

Types of Motor Control

Answer 8

Open-loop control

Closed-loop control

Question 9

Open-Loop Control

Answer 9

Does not require sensory feedback to be available and/or used to control movements

Want to see how far the golf ball goes after you hit it
Basketball free-throw
Find out the score after you are done (time, placement, etc)

Question 10

Closed-loop Control

Answer 10

Feedback is involved in the planning and execution of movements

As you are producing the movement, you are receiving feedback
How you swing towards the golf ball

Question 11

Input Process: Open-Loop

Answer 11

Input > Movement control center (cortex) > effectors (muscles, joints)

Question 12

Input Process: Closed-Loop

Answer 12

Input > movement control center (cortex) > Movement commands > Effectors (muscles, joints) > movement center (repeat)

Question 13

Open-loop system of control

Answer 13

fast movements
well learned movements
NO feedback used DURING execution

Question 14

Closed-loop system of control

Answer 14

Slow/precise movements

Feedback is used during execution = afferent (sensory) information is used to control movement

Question 15

Motor control theories

Answer 15

Reflex theories
Hierarchical Theories
Dynamical Approaches
Ecological Approaches

Question 16

Theory

Answer 16

A set of ideas used to explain a specific phenomenon

Question 17

Hypothesis

Answer 17

A testable statement about observed events

Question 18

Reflex Theories

Answer 18

Sherrington

Skinner

Question 19

Reflex Theories: Basic Assumptions

Answer 19

The reflex is the fundamental unit of motor control
A stimulus triggers the response (movement)
- There is no involvement of higher cortical centers, only the spinal cord (reflex)
Complex movements occur as a result of a chain of reflexes (reflex chaining models)
The individual is a passive recipient of externally produced sensory input

Question 20

Reflex Theories: Strengths and Weaknesses

Answer 20

Strength: simple explanation
Weak: TOO simple to account for a person’s ability to perform a wide variety of goal-directed actions (ex. anticipation)
Unable to explain how movements performed in the absence of sensory information (stimulus from environment)

Question 21

Hierarchical Theories: Basic Assumptions

Answer 21

All aspects of movement planning and execution are the sole responsibility of one or more cortical centers
-“top down” view of motor control
Sensory feedback is not essential for the execution of movements
Memory representations (Motor Programs): pre-structured sets of motor commands developed at the highest cortical level and sent to lower spinal centers

Question 22

Support for Hierarchical Models

Answer 22

Deafferentation Studies
Limb Block Studies
Response Complexity Studies

Question 23

Deafferentation Studies

Answer 23

Hierarchical Model

Show that movements can be performed in absence of feedback

Question 24

Limb Blocking Studies

Answer 24

Hierarchical Model

Show that activation pattern for agonist and antagonist muscles are planned in advanced for short duration movements

Question 25

Response Complexity Studies

Answer 25

Hierarchical Model | Reaction time increases as complexity of response increases (more time for planning movements)

Question 26

Strength of Hierarchical Models

Answer 26

1. Accounts for the ability to perform movements in the absence of feedback 2. The GMP allows the performance of a variety of movements by manipulating parameters 3. New movements are possible

Question 27

Dynamical/Ecological Approach

Answer 27

These theories represent a big "break" from the previous theories Both rely heavily on concepts "borrowed" from physics, mathematics, and/or ecological psychology

Question 28

Dynamical Systems

Answer 28

Self-Organization | From chaos into order

Question 29

Dynamical Systems: Self Organization

Answer 29

MOVEMENT: Individual > Environment > Task

Question 30

Dynamical Approach: Basic Assumptions

Answer 30

Self Organization: patterns emerge as a result of the interaction among the components of a system (individual, task, and environment) Attractor states: preferred patterns of coordination are adopted to enhance stability New movement patterns emerge as a result of scalar changes in one or more control parameters (control parameter: variable that can lead to change in behavior) The parameters that exhibit the nonlinear changes are identified using order parameters (order parameter: variables that are used to quantify the effect of a change in behavior)

Question 31

Ecological Approach: Basic Assumption

Answer 31

Focus on the perceptual interface between the individual and the environment Affordances: lawful properties of the environment that permit certain action Optical properties specific to an affordance can directly trigger action Continuous interaction occurring between the processes of perceiving and acting (perception/action coupling)

Question 32

Does one theoretical approach better explain how movements are controlled?

Answer 32

Hierarchical (GMP) theories are better in explaining a performer's actions in rule-based sport settings. Dynamical and ecological approaches better explain how well-learned skills (walking, standing...) are performed.

Question 33

Four characteristics of Human Actions

Answer 33

Flexibility Uniqueness Consistency Modifiability

Question 34

Flexibility

Answer 34

the ability to recruit different muscles and joints to achieve the same aciton

Question 35

Uniqueness

Answer 35

no two movements are ever performed in exactly the same way

Question 36

Consistency

Answer 36

temporal/spatial characteristics of a movement remain relatively stables from one performance to the next.

Question 37

Modifiability

Answer 37

the ability to alter a movement pattern, even as it is being executed.

Question 38

The Degrees of Freedom Problem (Bernstein)

Answer 38

How do individuals successfully organize a complex system of bones, joints, musculature that moves in a variety of different ways. Degree-of-Freedom: number of ways in which any given unit of control is capable of moving. -unit of control may be a joint, a muscle, or even a motor unit

Question 39

Two ways to solve the DOF problem

Answer 39

Muscle response synergy | Mechanical properties of the limbs

Question 40

Muscle Response Synergy

Answer 40

A group of muscles constrained to act as a single behavioral unit Some are innate: reaching, grasping, walking Some are learned: any sport skill

Question 41

Mechanical properties of the limbs

Answer 41

Using characters of muscles/joints and gravity can help movement without the need of muscles activation