Introductory Terminology: Lecture 1

Question 1

Motor control

Answer 1

Ability to regulate or direct the mechanisms essential to movement
- CNS and PNS
- coordination
- use of sensory information
- personal perception
- past experiences
- environment
- motor development

Question 2

Reflex theory of motor control

Answer 2

Complex behavior was explained through the combined action of individual reflexes chained together.

Does not explain movement that occurs in absence of a sensory stimulus nor novel movements

Reflex-based neurofacilitation approaches:
- PNF
- quick stretch
- contract relax
- tapping
(retraining motor control through techniques designed to facilitate and/or inhibit different movement patterns)

Question 3

Hierarchical theory of motor control

Answer 3

Organization control is top down; each successively higher level exerts control over level below it

Vertical hierarchy: lines of control do not cross; never bottom-up control

Cannot explain dominance of reflex behavior in certain situations in normal adults

Explains disordered motor control in patients with neurologic disorders

Question 4

Ecological theory of motor control

Answer 4

The perception/action system actively explores the environment to satisfy its goals

• assess environmental properties in relation to our own characteristics
• action is dependent on how well an individual fits within environmental constraints
• action facilitates perception and perception facilitates action

Question 5

Perception-action coupling

Answer 5

The linking together of information and actions or movements

Perception
- detection and utilization of critical information for the control of action
- Ex: hand-eye coordination

Action
- various movements that are regulated by the perceived information
- Ex: stepping off the bottom stair without vision (anticipatory)

Question 6

Motor program-based theory

Answer 6

Retraining movements are important to functional tasks, not just specific muscles in isolation

Responsible for adaptive and flexible qualities of human movement

Each motor program controls a class of actions

The basis for generating movement prior to and during the performance of an action

Question 7

Motor programming theory

Answer 7

“Schema theory”

Memory based mechanism that controls coordinated movement

Central motor program:
- more flexible than a reflex
- activated by sensory stimuli or central processes

If stimulus is absent, a concept for a central motor pattern remains

Question 8

Systems theory

Answer 8

Dynamic systems theory

Emphasizes environmental information, mechanical and dynamic properties of the body/limbs in movement control/coordination

Behavioral changes are not always continuous, linear progressions but are often sudden or abrupt

Behavior is organized by the interactions among task, environmental, and organism constrains

Behavior self-organize in response to constraints

Small amount of variability indicates highly stable, energy efficient behavior

Question 9

Open loop system

Answer 9

the control center sends the effectors all the movement instructions they need to perform a skill from beginning to end

control center –> instruction –> effectors

Question 10

Closed loop system

Answer 10

Includes feedback as part of the system

The control center sends movement instructions to the effector that enable them to initiate the performance of a skill

Feedback from effectors and other sources provides the control center with the information needed to give the effectors the instructions to continue and end the movement

control center –> instruction –> effector –> information –> control center –> loop

Question 11

Degrees of freedom

Answer 11

Number of independent elements in a system and the ways each element can act

More than 100

Problem –> How to control degrees of freedom to make a complex system act in a specific way?
- Freeze: reduce movement degrees of freedom
- Free: increase movement degrees of freedom

Question 12

Synergies

Answer 12

Groups of muscles (and joints) acting as functional units; patterning of body and limb motions relative to environmental objects/events

• play role in solving degrees of freedom problem
• ensure flexible and stable performance of motor tasks
• develop through practice and experience

Question 13

Summary of motor control theories

Answer 13

Motor program-based theory, dynamic systems theory BEST

motor control theory cannot focus exclusively on movement information specified by CNS

Theory hybrid could explain control of coordinated movement

Question 14

Motor abilities as individual difference variables

Answer 14

If 2 people have the same
- amount of practice
- level and amount of instruction
- motivation to perform the skill
Then motor abilities will influence the level of performance success each person can achieve

Question 15

General motor ability hypothesis

Answer 15

• Many motor abilities are highly related
• A person can be described as having global motor ability

Question 16

Specificity of motor ability hypothesis

Answer 16

• Many motor abilities are relatively independent
• Each person varies in the amount of each ability
• A person’s motor ability can be described by a profile of amount of each specific motor ability

Question 17

Fleishman’s taxonomy of motor abilities

Answer 17

• multi-limb coordination
• control precision
• response orientation
• reaction time
• speed of arm movement
• rate control (anticipating obstacles, conditions)
• manual dexterity
• finger dexterity
• arm-hand steadiness
• wrist, finger speed
• aiming

Question 18

Reaction time

Answer 18

From “go” to initiation of response
- simple (one target, one finger)
- choice (multiple targets, respective fingers)
- discrimination (multiple targets, one finger)

RT + MT = response time

Question 19

Movement time

Answer 19

From initiation of response to termination of response

RT + MT = response time

Question 20

Regulatory conditions

Answer 20

Features of the object or environment to which movements must conform to achieve action goal

Spatial and temporal aspects of the movement are regulated

Question 21

Non-regulatory conditions

Answer 21

Features of the object or environment that have no effect or an indirect effect on movement; movement does not have to conform to these features

Question 22

Intertrial variability

Answer 22

Variations in the regulatory conditions from one trial to the next

Question 23

Closed motor skills/environment

Answer 23

Stationary support surface, object, and/or other people/animals

The performer determines when to begin the action

Predictable (closed)
- gymnastics
- typing
- cutting vegetables

Question 24

Open motor skills/environment

Answer 24

Involves a supporting surface, object, and/or other people/animal in motion

Environmental features determine when to begin the action

Unpredictable (open)
- soccer
- wrestling
- chasing a rabbit

Question 25

Motor skill performance outcome measures

Answer 25

Indicates the outcome or result of performing a motor skill

Does not tell us about the movements that led to the outcome

Does not provide information about the activity of various muscles involved or how the nervous system was involved

Ex: jump height; throwing accuracy; TUG time

Question 26

Motor skill performance production measures

Answer 26

Indicate the activity of specific aspects of the motor control system during the performance

Ex: high jump technique; angle of each joint of the arm during a throw; TUG movement analysis

Question 27

Characteristics of Gentile’s Taxonomy

Answer 27

Each category puts different demands on the performer

Skill complexity is the basis for taxonomy organization

Complexity increases when a motor skill involves one or more of the following
- open environment
- trial-to-trial variability
- object manipulation
- body transport

Question 28

Practical uses of Gentile’s Taxonomy

Answer 28

Guides evaluation of motor performance capabilities, limitations, deficiencies

Provides a systematic basis for selecting progressions

Chart an individual’s progress

Question 29

Manipulative vs. non-manipulative

Answer 29

maintaining/changing position of moveable objects

Question 30

Bimanual coordination skills

Answer 30

Motor skills that require simultaneous use of two arms

Symmetric:
- rowing a boat, jumping rope

Asymmetric:
- playing a guitar
- driving stick shift

Temporal and spatial coupling of the two arms when initially performing an asymmetric bimanual skill
- practice required to disassociate the two limbs

Question 31

Discrete motor skills

Answer 31

specified beginning and end points, usually require a simple movement

Question 32

Serial motor skills

Answer 32

involve a continuous series of discrete skills

Question 33

Continuous motor skills

Answer 33

no recognizable beginning or end points; usually involve repetitive uninterrupted movements