Week 4

Question 1

What is Motor Control?

Answer 1

The ability to regulate or direct the mechanisms essential to movement

Question 2

Factors affecting MOVEMENT

Answer 2

individual
task
environment

Question 3

individual systems underlying motor control

Answer 3

sensory/perceptual systems

cognition

motor/action systems

Question 4

Reflex Theory

Answer 4

Sir Charles Sherrington: The
Integrative Action of the Nervous
System (1906)

Reflexes are building blocks of
complex behavior

Question 5

Reflex Theory: Limitations

Answer 5

What about voluntary movement?

Does not explain or predict movement without sensory input

Does not explain learned/fast behaviors (typing)

What about a single stimulus that can produce varied responses
(override reflexes)?

Does not explain novel movements

Question 6

Reflex Theory: Clinical Implications

Answer 6

Part of the examination/observation in developmental assessment

Part of the examination/observation in people with neurological conditions

Question 7

Hierarchical Theory

Answer 7

Top down control

Lower levels controlled by higher levels

Originally explained why reflexes were predominant in CNS dysfunction
(e.g., TBI) - higher levels lost control
over lower levels

Question 8

Hierarchical Theory / Maturation Theory
LIMITATIONS:

Answer 8

Cannot explain dominance of reflex and reflex-like behavior in certain
situations (chewing, swallowing, central pattern generator in spinal
cord

Early leg movements can be controlled voluntarily

Question 9

Hierarchical Theory
CLINICAL IMPLICATIONS:

Answer 9

When combined with reflex theory was used to explain dysfunctional
motor control in people with neurologic disorder

Real foundation of Brunnstrom and Bobath

Part of the examination/observation in pediatric assessment

Foundation for the developmental sequence (i.e. roll-sit-crawl-stand)

Directionality (cephalocaudal, proximodistal, gross->fine, general->specific)

Question 10

Motor Programming Theories

Answer 10

Movement is possible without reflexive action/in isolation from
sensory feedback

Central pattern generators (spinally mediated motor programs)

Neural connections that are stereotyped and hardwired

Sensory input, while not necessary, has important function in
modulating motor output (motor action)

Question 11

Motor Programming Theories
LIMITATIONS:

Answer 11

Sensory input still important for
controlling movement

CPG not the sole determinant of
action – affected by context (ie.
gravity, fatigue)

Question 12

Motor Programming Theories
CLINICAL IMPLICATIONS:

Answer 12

Move beyond reflex-based theories
for dysfunctional motor control

Focus on retraining movement(s)
important to FUNCTIONAL TASKS,
not just specific muscles in isolation

Question 13

Systems Theory

Answer 13

Bernstein, Russian scientist, in the early-mid 1900’s recognized that you cannot understand motor control without considering the
internal and external forces acting on the body

Takes into account the initial condition and external conditions
affecting movement.

“Coordination of movement is the process of mastering the
redundant degrees of freedom of the moving organism” (Bernstein,
1967)

Question 14

Synergies

Answer 14

Introduced by Bernstein

Synergies are not used by the nervous system to eliminate redundant
degrees of freedom, but instead to ensure flexible and stable performance of
motor tasks. They call this the ‘principle of abundance

Question 15

Neural organization of multi-element system (e.g., muscles)

Answer 15

Organizes sharing a task

Provides variation among elemental variables (e.g., muscles) for the purpose
of stabilization and flexibility

Example: maintaining postural control while reaching

Question 16

Dynamic Systems Theory

Answer 16

Evolution of Systems Theory that recognizes ‘self-organization’ and
asks the questions:

How do patterns and organization come into being from orderless
constituent parts?

How do these systems change over time?

Behavior is non-linear (moving toward explaining complex behavior)

Question 17

Systems Theories LIMITATIONS:

Answer 17

De-emphasizes role of nervous
system in motor control

Question 18

Systems Theories
CLINICAL IMPLICATIONS:

Answer 18

Stresses body as a mechanical
system

Understanding dynamic properties
of human movement helps to aid
in recovery (i.e. speed – TM training s/p SCI)

Question 19

Ecological Theory

Answer 19

James Gibson (psychologist in the 1960’s) explored ways for our motor system to interact most effectively with the environment in
order to perform:
GOAL-ORIENTED BEHAVIOR

Motor control evolved based on need to cope with the environment

Less emphasis on sensory/motor interplay and shift to PERCEPTION

Question 20

Ecological Theory
LIMITATIONS:

Answer 20

De-emphasizes organization &
function of nervous system

Question 21

Ecological Theory
CLINICAL IMPLICATIONS:

Answer 21

Active exploration of the
environment allows for multiple
ways to accomplish a task
(adaptability)
* Goal-oriented
* Values perception

Question 22

What is the best theory
of motor control?

Answer 22

Integrated Systems-Based Theory