MOTOR CONTROL - THEORIES

2. LEARNING OBJECTIVES
STUDENTS WILL BE ABLE TO –
DEFINE MOTOR CONTROL, AND DISCUSS ITS RELEVANCE TO THE CLINICAL
T/T OF PATIENTS WITH MOVEMENT PATHOLOGY.
DISCUSS HOW FACTORS RELATED TO THE INDIVIDUAL, THE TASK, AND THE
ENVIRONMENT AFFECT THE ORGANIZATION AND CONTROL OF MOVEMENT.
ENUMERATE THE THEORIES OF MOTOR CONTROL AND ITS VALUE TO
CLINICAL PRACTICE
COMPARE AND CONTRAST THE NEUROFACILITATION APPROACHES TO THE
TASK ORIENTED APPROACH.

3. INTRODUCTION
•DEFINITION:
MOTOR CONTROL IS DEFINED AS THE ABILITY TO REGULATE OR DIRECT
THE MECHANISMS ESSENTIAL TO MOVEMENT.
•THE FIELD OF MOTOR CONTROL IS DIRECTED AT:
 STUDYING THE NATURE OF MOVEMENT
HOW MOVEMENT IS CONTROLLED.

4. WHY SHOULD THERAPIST STUDY MOTOR CONTROL?
•DIRECTED AT CHANGING MOVEMENT OR INCREASING THE CAPACITY TO
MOVE.
•STRATEGIES - DESIGNED TO IMPROVE THE QUALITY AND QUANTITY OF
POSTURE AND MOVEMENTS ESSENTIAL TO FUNCTION.

5. NATURE OF MOVEMENT
•MOVEMENT EMERGES FROM INTERACTION OF THREE FACTORS:
“THE INDIVIDUAL, THE TASK AND THE ENVIRONMENT”.
M
TASK
ENVIRONMENTINDIVIDUAL

6. FACTORS WITHIN THE INDIVIDUAL THAT CONSTRAINT
MOVEMENT

7. TASK CONSTRAINTS ON MOVEMENT
MOVEMENT
STABILITY
MOBILTY
MANIPULATION

8. • BUT WHAT TASKS SHOULD BE TAUGHT?
• IN WHAT ORDER?
• WHAT TIME?
• THUS UNDERSTANDING OF TASK ATTRIBUTES CAN PROVIDE A FRAMEWORK FOR STRUCTURING TASKS.
• TASKS CAN BE SEQUENCED FROM LEAST TO MOST DIFFICULT BASED ON THEIR RELATIONSHIP TO A
SHARED ATTRIBUTE..
• CONCEPT OF GROUPING AND CLASSIFYING TASKS
 FUNCTIONAL TASK GROUPINGS.
 ACCORDING TO CRITICAL ATTRIBUTES.
MOBILITY TASKS
MANIPULATION COMPONENT
MOVEMENT VARIABILITY

9. FUNCTIONAL TASK GROUPING
Functional
categories

10. FUNCTIONAL TASK GROUPING

12. MANIPULATION COMPONENT
Standing and lifting a heavy
load
Standing and
lifting a light load
standing

13. MOVEMENT VARIABILITY
STABILITY QUASIMOBILE MOBILITY
Closed predictable
environment
sit/stand/non-
moving surface
Sit to stand/
kitchen chair/arms
Walk/non-moving
surface
Open
unpredictable
environment
Stand/rocker board Sit to
stand/rocking chair
Walk on uneven or
moving surface

14. ENVIRONMENTAL CONSTRAINTS ON MOVEMENT
MOVEMENT
REGULATORY
NON
REGULATORY

15. THE CONTROL OF MOVEMENT: THEORIES OF MOTOR
CONTROL
•A THEORY OF MOTOR CONTROL IS A GROUP OF IDEAS ABOUT THE
CONTROL OF MOVEMENT.
•A THEORY IS A SET OF INTERCONNECTED STATEMENT THAT
DESCRIBES UNOBSERVABLE STRUCTURES OR PROCESSES AND RELATE
THEM TO EACH OTHER AND TO OBSERVABLE EVENTS.

16. VALUE OF THEORY TO PRACTICE
THEORY PROVIDES -
FRAME WORK FOR INTERPRETING
BEHAVIOUR
GUIDE FOR CLINICAL ACTION
NEW IDEAS: DYNAMIC & EVOLVING
WORKING HYPOTHESIS FOR
EXAMINATION & INTERVENTION

17. THEORIES
REFLEX HIERACHICAL
MOTOR PROGRAMMING SYSTEMS
DYNAMIC ACTION ECOLOGICAL

18. REFLEX THEORY
• ESTABLISHED BY CHARLES SHERRINGTON, A NEUROPHYSIOLOGIST.
• HIS RESEARCH ON SENSORY RECEPTORS LEAD TO VIEW THAT MOVEMENT WAS RESULT
OF STIMULUS-RESPONSE SEQUENCE OF EVENTS OR REFLEX BASED
• STIMULUS RESPONSE
• SENSATION ASSUMED A PRIMARY ROLE IN INITIATION AND PRODUCTION OF
MOVEMENT.
• HE BELIEVED ,REFLEXES WERE THE BUILDING BLOCKS OF COMPLEX BEHAVIOR.

19. LIMITATIONS
• THE REFLEX CANNOT BE CONSIDERED THE BASIC UNIT OF BEHAVIOUR IF BOTH SPONTANEOUS AND
VOLUNTARY MOVEMENTS ARE RECOGNISED AS ACCEPTABLE CLASSES OF BEHAVIOUR AS IT MUST BE ACTIVATED
BY AN OUTSIDE AGENT.
• DOES NOT ADEQUATELY EXPLAIN AND PREDICT MOVEMENT THAT OCCURS IN THE ABSENCE OF SENSORY
STIMULUS. E.G ANIMALS MOVE – ABSENCE OF SENSORY STIMULUS
• DOES NOT ADEQUATELY EXPLAIN FAST MOVEMENTS.SEQUENCE OF MOVEMENTS THAT OCCUR TOO RAPIDLY TO
ALLOW SENSORY FEEDBACK FROM PRECEDING MOVEMENT TO TRIGGER THE NEXT E.G TYPING
• FAILS TO EXPLAIN THE FACT THAT A SINGLE STIMULUS CAN RESULT IN VARYING RESPONSES DEPENDING ON
CONTEXT AND DESCENDING COMMANDS. E.G OVERRIDE REFLEXES TO ACHIVE GOAL.
• DOES NOT EXPLAIN THE ABILITY TO PRODUCE NOVEL MOVEMENTS. E. G VIOLINIST

20. CLINICAL IMPLICATIONS
•CLINICAL STRATEGIES DESIGNED TO TEST REFLEXES SHOULD ALLOW
THERAPISTS TO PREDICT FUNCTION.
•PATIENT’S MOVEMENT BEHAVIORS WOULD BE INTERPRETED IN TERMS
OF THE PRESENCE OR ABSENCE OF CONTROLLING REFLEXES.
•RETRAINING MOTOR CONTROL FOR FUNCTIONAL SKILLS WOULD FOCUS
ON ENHANCING OR REDUCING THE EFFECT OF VARIOUS REFLEXES
DURING MOTOR TASKS. E.G FACILITATION / INHIBITION.

21. HIERARCHICAL THEORY
•MANY RESEARCHERS HAVE CONTRIBUTED TO THE VIEW THAT NERVOUS
SYSTEM IS ORGANIZED AS A HIERARCHY.
•AMONG THEM, HUGHLINGS JACKSON, AN ENGLISH PHYSICIAN ARGUED THAT
THE BRAIN HAS HIGHER, MIDDLE AND LOWER LEVELS OF CONTROL, EQUATED
WITH HIGHER ASSOCIATION AREAS, THE MOTOR CORTEX AND THE SPINAL
LEVELS OF MOTOR FUNCTION.
•THE HIERARCHICAL CONTROL MODEL IS CHARACTERIZED BY A TOP-DOWN
STRUCTURE, IN WHICH HIGHER CENTERS ARE ALWAYS IN CHARGE OF LOWER
CENTERS.

22. CURRENT CONCEPTS RELATED TO HIERARCHICAL CONTROL
• THE CONCEPT OF STRICT HIERARCHY HAS BEEN MODIFIED.
• WITHIN THIS MODIFICATION, THE ASSOCIATION CORTEX OPERATES AS THE HIGHEST
LEVEL(ELABORATING PERCEPTION AND PLANNING STRATEGIES)
• WHILE SENSORY-MOTOR CORTEX IN ASSOCIATION WITH THE PORTIONS OF THE BASAL
GANGLIA, BRAIN STEM AND CEREBELLUM FUNCTION AS THE MIDDLE LEVEL(CONVERTING
STRATEGIES INTO MOTOR PROGRAMS AND COMMANDS). THE SPINAL CORD FUNCTIONS AT
THE LOWEST LEVEL, TRANSLATING COMMANDS INTO MUSCLE ACTIONS RESULTING IN THE
EXECUTION OF MOVEMENT.
• MODERN HIERARCHICAL THEORY PROPOSES THAT THE THREE LEVELS DO NOT OPERATE IN A
RIGID, TOP-DOWN ORDER BUT RATHER AS A FLEXIBLE SYSTEM IN WHICH EACH LEVEL CAN
EXERT CONTROL ON THE OTHERS.
• SHIFTS IN CONTROL ARE DEPENDENT ON THE DEMANDS AND COMPLEXITY OF THE TASK
WITH THE HIGHER CENTERS ALWAYS ASSUMING CONTROL.

23. LIMITATIONS
• CANNOT EXPLAIN THE DOMINANCE OF REFLEX BEHAVIOUR IN CERTAIN SITUATIONS
IN NORMAL ADULTS. E.G.. STEPPING ON A PIN RESULTS IN AN IMMEDIATE
WITHDRAWAL OF LEG. THIS IS AN EXAMPLE OF A REFLEX WITHIN THE LOWEST LEVEL
OF HIERARCHY DOMINATING MOTOR FUNCTION.
• LIMITATION OF HIERARCHICAL THEORY REFLEX WITHIN THE LOWEST LEVEL OF THE
HIERARCHY DOMINATING MOTOR FUNCTION. (BOTTOM UP CONTROL)
• ALL LOW-LEVEL BEHAVIOURS ARE PRIMITIVE, IMMATURE AND NON-ADAPTIVE,
WHILE ALL HIGHER LEVEL (CORTICAL) BEHAVIOURS ARE MATURE, ADAPTIVE AND
APPROPRIATE.

24. CLINICAL IMPLICATIONS
• SIGNE BRUNNSTROM, USED A REFLEX HIERARCHICAL THEORY TO DESCRIBE DISORDERED
MOVEMENT FOLLOWING A MOTOR CORTEX LESION.
• SHE STATED “WHEN THE INFLUENCE OF HIGHER CENTERS IS TEMPORARILY OR PERMANENTLY
INTERFERED WITH THE NORMAL REFLEXES BECOME EXAGGERATED AND SO CALLED
PATHOLOGICAL REFLEXES APPEAR”.
• “THE RELEASE OF MOTOR RESPONSES INTEGRATED AT LOWER LEVELS FROM RESTRAINING
INFLUENCES OF HIGHER CENTERS, ESPECIALLY THAT OF THE CORTEX LEADS TO ABNORMAL
POSTURAL REFLEX ACTIVITY”(BOBATH,1965;MAYSTON,1922).

25. MOTOR PROGRAMMING THEORIES
• REFLEX THEORIES HAVE BEEN USEFUL IN EXPLAINING CERTAIN STEREOTYPED PATTERNS OF
MOVEMENT.
• ONE CAN REMOVE THE STIMULUS, OR THE AFFERENT INPUT AND STILL HAVE A PATTERNED
MOTOR RESPONSE.(VAN SANT,1987).
• E.G GRASSHOPPER – FLIGHT DEPENDED ON RHYTHMIC PATTERN GENERATOR. EVEN WHEN
SENSORY NERVES WERE CUT, THE NERVOUS SYSTEM COULD GENERATE THE OUTPUT WITH
NO SENSORY INPUT – BUT WING BEAT WAS SLOW

26. MOTOR PROGRAMMING THEORIES
• CONCEPT OF CENTRAL MOTOR PATTERN, IS MORE FLEXIBLE THAN THE CONCEPT OF A
REFLEX BECAUSE IT CAN BE EITHER ACTIVATED BY SENSORY STIMULI OR BY CENTRAL
PROCESSES. THE TERM MOTOR PROGRAM MAY BE USED TO IDENTIFY A CENTRAL PATTERN
GENERATOR(CPG).
• CENTRAL PATTERN GENERATOR (CPG)- SPECIFIC NEURAL CIRCUIT IN SPINAL CORD –NEURAL
NETWORKS THAT CAN ENDOGENOUSLY (I.E. WITHOUT RHYTHMIC SENSORY OR CENTRAL
INPUT) PRODUCE RHYTHMIC PATTERNED OUTPUTS OR AS NEURAL CIRCUITS THAT
GENERATE PERIODIC MOTOR COMMANDS FOR RHYTHMIC MOVEMENTS SUCH AS
LOCOMOTION.

27. LIMITATIONS
•CENTRAL MOTOR PROGRAM CANNOT BE CONSIDERED AS SOLE
DETERMINANT OF ACTION.
•MOTOR PROGRAM CONCEPT DOES NOT TAKE INTO ACCOUNT
MUSCULOSKELETAL SYSTEM AND ENVIRONMENTAL VARIABLES

28. CLINICAL IMPLICATIONS
•IN PATIENTS WHOSE HIGHER LEVELS OF MOTOR PROGRAMMING ARE
AFFECTED, MOTOR PROGRAM THEORY HELPS PATIENTS RELEARN CORRECT
RULES FOR ACTION.
•INTERVENTION SHOULD FOCUS ON RETRAINING MOVEMENTS IMPORTANT
TO A FUNCTIONAL TASK, NOT JUST ON RE-EDUCATING SPECIFIC MUSCLES
IN ISOLATION.

29. SYSTEMS THEORY
•BERNSTEIN,1967 LOOKED AT THE WHOLE BODY AS A MECHANICAL SYSTEM,
WITH MASS AND SUBJECT TO BOTH EXTERNAL FORCES SUCH AS GRAVITY
AND INTERNAL FORCES INCLUDING BOTH INERTIAL AND MOVEMENT
DEPENDENT FORCES.
•HE ALSO NOTED THAT WE HAVE MANY DEGREES OF FREEDOM.
•HIGHER LEVELS OF THE NERVOUS SYSTEM ACTIVATE LOWER LEVELS, WHILE
LOWER LEVELS ACTIVATE SYNERGIES OR GROUP OF MUSCLES THAT ARE
CONSTRAINED TO ACT TOGETHER AS A UNIT

30. LIMITATIONS
•SYSTEMS THEORY DOES NOT FOCUS HEAVILY ON THE INTERACTION OF
THE ORGANISM WITH THE ENVIRONMENT.

31. CLINICAL IMPLICATIONS
•EXAMINE THE CONTRIBUTION OF IMPAIRMENTS IN THE MUSCULOSKELETAL AS
WELL AS NEURAL SYSTEM.
•INTERVENTION MUST FOCUS NOT ONLY ON THE IMPAIRMENTS WITHIN THE
INDIVIDUAL SYSTEM, BUT AMONG THE MULTIPLE SYSTEMS

32. DYNAMIC ACTION THEORY
• THE DYNAMIC ACTION THEORY APPROACH TO MOTOR CONTROL HAS BEGUN TO LOOK AT THE MOVING
PERSON FROM A NEW PERSPECTIVE.(KAMM 1991, KELSO AND TULLER ,1984;KUGLER AND TURVEY1987)
• THE PERSPECTIVE COMES FROM THE BROADER STUDY OF DYNAMICS AND SYNERGETIC.
• “FUNDAMENTAL DYNAMIC SYSTEMS PRINCIPLE.”
IT SAYS THAT WHEN A SYSTEM OF INDIVIDUAL PARTS COME TOGETHER , IT’S ELEMENTS BEHAVE
COLLECTIVELY IN AN ORDERED WAY.
• THIS PRINCIPLE APPLIED TO MOTOR CONTROL PREDICTS THAT MOVEMENT COULD EMERGE AS A RESULT
OF INTERACTING ELEMENTS WITHOUT THE NEED FOR SPECIFIC COMMANDS OR MOTOR PROGRAMS
WITHIN THE NERVOUS SYSTEM.
• E.G – THOUSAND MUSCLE CELLS OF HEART WORK TOGETHER AS A SINGLE UNIT – HEART BEAT

33. DYNAMIC ACTION THEORY
•DYNAMIC THEORY STATES THAT THE NEW MOVEMENT EMERGES DUE TO A
CRITICAL CHANGE IN IN ONE OF THE SYSTEMS CALLED “CONTROLLED
PARAMETER”.- A VARIABLE THAT REGULATES CHANGE IN BEHAVIOUR OF THE
ENTIRE SYSTEM.
•DYNAMIC ACTION THEORY HAS BEEN MODIFIED TO INCORPORATE MANY OF
BERNSTEIN'S CONCEPTS ‘”DYNAMIC SYSTEM MODEL” SUGGESTS THAT
MOVEMENT UNDERLYING ACTION RESULTS FROM INTERACTION OF BOTH
PHYSICAL AND NEURAL COMPONENTS.

34. LIMITATIONS
•A LIMITATION OF THIS MODEL CAN BE THE PRESUMPTION THAT THE NERVOUS
SYSTEM HAS FAIRLY UNIMPORTANT ROLE AND THAT THE RELATIONSHIP
BETWEEN THE PHYSICAL SYSTEM OF THE ANIMAL AND THE ENVIRONMENT IN
WHICH IT OPERATES PRIMARILY DETERMINES THE ANIMAL’S BEHAVIOUR.

35. CLINICAL IMPLICATIONS
• ONE OF THE MAJOR IMPLICATION OF THE DYNAMIC ACTION THEORY IS MOVEMENT
IS AN EMERGENT PROPERTY.
• IT EMERGES FROM THE INTERACTION MULTIPLE ELEMENTS THAT SELF ORGANIZE
BASED ON CERTAIN DYNAMIC PROPERTIES OF THE ELEMENTS THEMSELVES.
• MOVEMENT BEHAVIOUR CAN OFTEN BE EXPLAINED IN TERMS OF PHYSICAL
PRINCIPLES RATHER THAN IN TERMS OF NEURAL STRUCTURES
• CAN MAKE USE IN HELPING PATIENTS TO REGAIN MOTOR CONTROL

36. ECOLOGICAL THEORY
• IN 1960S,JAMES GIBSON EXPLORES THE WAY IN WHICH OUR MOTOR SYSTEMS ALLOW US TO INTERACT
MOST EFFECTIVELY WITH THE ENVIRONMENT TO PERFORM GOAL-ORIENTED BEHAVIOR.
• ACTIONS REQUIRE PERCEPTUAL INFORMATION THAT IS SPECIFIC TO A DESIRED GOAL-DIRECTED
ACTION PERFORMED WITHIN A SPECIFIC ENVIRONMENT.
• PERCEPTION FOCUSES ON DETECTING INFORMATION IN THE ENVIRONMENT THAT WILL SUPPORT THE
ACTIONS NECESSARY TO ACHIEVE THE GOAL.
• ECOLOGICAL PERSPECTIVE HAS BROADENED OUR UNDERSTANDING OF NERVOUS SYSTEM FUNCTION
FROM THAT OF SENSORY/MOTOR SYSTEM ,REACTION TO ENVIRONMENTAL VARIABLES TO THAT OF
PERCEPTION /ACTION SYSTEM THAT ACTIVELY EXPLORES THE ENVIRONMENT TO SATISFY ITS OWN
GOAL.

37. LIMITATIONS
•GIVE LESS EMPHASIS TO THE ORGANIZATION AND FUNCTION OF THE
NERVOUS SYSTEM THAT HAS LED TO THIS INTERACTION, MORE ON
ORGANISM/ENVIRONMENT INTERFACE

38. CLINICAL IMPLICATIONS
• A MAJOR CONTRIBUTION OF THIS VIEW IS IN DESCRIBING THE INDIVIDUAL AS AN ACTIVE
EXPLORER TO THE ENVIRONMENT.
• AN IMPORTANT PART OF INTERVENTION IS HELPING THE PATIENT EXPOLRE THE POSSIBILITIES
FOR ACHIEVING A FUNCTIONAL TASK IN MULTIPLE WAYS
• THE ABILITY TO DEVELOP MULTIPLE ADAPTIVE SOLUTIONS TO ACCOMPLISH A TASK AND
DISCOVER THE BEST SOLUTION FOR THEM, GIVEN THE PATIENTS SET OF LIMITATIONS.

39. WHICH IS THE BEST THEORY OF MOTOR CONTROL
•THE BEST AND MOST COMPLETE THEORY OF MOTOR CONTROL, THE ONE
THAT REALLY PREDICTS THE NATURE AND CAUSE OF MOVEMENT AND IS
CONSISTENT WITH OUR CURRENT KNOWLEDGE OF BRAIN ANATOMY AND
PHYSIOLOGY?
•THERE IS NO ONE THEORY THAT HAS IT ALL
•BEST THEORY-THAT COMBINES ELEMENTS FROM ALL THE THEORIES
PRESENTED

40. NEUROLOGIC REHABILITATION: REFLEX BASED
NEUROFACILITATION APPROACHES
• NEUROFACILITATION APPROACHES INCLUDE BOBATH(KARL AND BERTA BOBATH,1965), THE
ROOD APPROACH(MARGARET ROOD,1967), BRUNNSTROM APPROACH(SIGNE
BRUNNSTROM,1966) , PNF(VOSS,1985) , SENSORY INTEGRATION THERAPY(JEAN AYRES,1972).
• THESE WERE BASED ON ASSUMPTIONS DRAWN FROM BOTH THE REFLEX AND HIERARCHICAL
THEORIES OF MOTOR CONTROL.
• THEY FOCUS ON RETRAINING MOTOR CONTROL THROUGH TECHNIQUES DESIGNED TO
FACILITATE AND/OR TO INHIBIT DIFFERENT MOTOR PATTERNS

41. CLINICAL IMPLICATIONS
• EXAMINATION OF MOTOR CONTROL SHOULD FOCUS ON IDENTIFYING THE PRESENCE OR
ABSENCE OF NORMAL AND ABNORMAL REFLEXES CONTROLLING MOVEMENT.
• INTERVENTIONS SHOULD BE DIRECTED AT MODIFYING THE REFEXES THAT CONTROL
MOVEMENT
• THE IMPORTANCE FOR SENSORY INPUT FOR STIMULATING NORMAL MOTOR OUTPUT
SUGGESTS AN INTERVENTION FOCUS OF MODIFYING THE CNS THROUGH SENSORY
STIMULATION

42. TASK-ORIENTED APPROACH
• BASED ON NEWER THEORIES OF MOTOR CONTROL
• IT IS ASSUMED THAT THE NORMAL MOVEMENT EMERGES AS AN INTERACTION AMONG
MANY SYSTEMS.
• MOVEMENT IS ORGANIZED AROUND A BEHAVIORAL GOAL AND IS CONSTRAINED BY THE
ENVIRONMENT.
• CLINICAL IMPLICATION - TASK ORIENTED APPROACH TO INTERVENTION ASSUMES THAT
PATIENTS LEARN BY ACTIVELY ATTEMPTING TO SOLVE THE PROBLEMS INHERENT IN A
FUNCTIONAL TASK RATHER THAN REPETITIVELY PRACTICING NORMAL PATTERNS OF
MOVEMENT