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10/20/2017
1
The heart and science of medicine.
UVMHealth.org/MedCenter
Motor Learning In Ortho and Beyond
Jon Robinson PT, DPT, NCS
Clinical Lead Physical Therapist
University of Vermont Medical Center
• Medial collapse in running
Movement Dysfunction
• Medial collapse in running
Movement Dysfunction
Willy et. al. Clin Biomechanics 2012
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• Ability to regulate or direct the mechanisms essential to movement.
• How all kinds of movements are controlled, body segments
coordinated/organized to produce movement, particularly given
degrees of freedom
• How the CNS is organized so that many individual muscles and
joints become coordinated
• How sensory information is used in the control of movement and how this information allows a person to select and plan an action.
Motor Control
Motor Control Theory
� How you think the system works directly influences how you prioritize and implement treatment when the system malfunctions
• Degrees of freedom
– Multitude of independent ways a system can act
• How can degrees of freedom be best organized to achieve goal?
Motor Control Theory
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• Theories must account for behavior
• Movements are:
– Flexible
– Unique
– Consistent
– Modifiable
Motor Control Theory
Borghese et al. J Physiol 1996
• General Motor Programming Theory
• Dynamic Systems Theory
• Uncontrolled Manifold Hypothesis
Motor Control Theory
• Movement planning & execution are responsibility of cortical command centers
• Movements stored in form of Generalized Motor Program (GMP)
General Motor Program Theory
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• Write your name
– Change limb
– Change force
– Change speed
Motor Equivalence
Schmidt & Lee, Motor Control and Learning, 2005
• Abstract representation of stored pattern for class of actions
• Pre-structured set of movement commands
• Organizes many degrees of freedom into single unit for efficient and effective action
• Invariant features: stored
• Relative timing & sequencing
• Parameters: modifiable features of GMP
– Time/speed
– Amplitude
– Effectors
Generalized Motor Program
• What are the potential implications of interventions with regard to motor control?
Implications
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• Motor behavior emerges from interaction of multiple subsystems
• Actions shaped by intention of performer and constraints of environment
• System self-organizes
– Order parameters of coordination
– Control parameters of context
– Organized based on attractor state of
efficiency & low variability
Dynamic Systems Theory
• Perception-action coupling
– The coordination of the visual perception of the relevant external
stimulus and the movement required to achieve the action goal.
– Our perception of important factors in the environment and our
abilities paired against the environment drives movement
– Tau
• Time to contact is specified according to the relative rate of change
of the size of the image of the object on the retina of the eye.
• Obstacle clearance
• Reach to grasp
Dynamic Systems Theory
Attractor States
Transition
In-Phase
Anti-Phase
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Comparison
GMP Dynamic Systems
Invariant features of coordinationstored in CNS
Parameters of speed, force, amplitude, and
limb added to generate schema
Control parameters of speed, force, amplitude,
goals, mechanics
Order parameters of coordination organized based on attractor state of stability & efficiency
• More variability in segment orientation/joint displacements than in endpoint position.
• Some of this variability contributes to the task goal, some does not.
• The set (manifold) of system configurations (neurons, muscles, joints) that do not change the outcome measure of performance (e.g., endpoint position) are not controlled. Schoner, Ecol Psych, 1995
• This allows flexibility & adaptability of movement.
Uncontrolled Manifold Hypothesis
Joint displacement
variability
Uncontrolled Manifold Hypothesis
Hammer endpoint
variability
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• How is movement controlled once initiated?
– Closed-Loop
– Open-Loop
Controlling Movement
• Use of feedback, error detection & correction to maintain desired goal
Closed-Loop Control
control
center
commands
feedback
effectors
comparator
• Centrally determined, pre-structured commands to effectors without use of feedback during movement
Open-Loop Control
control
centereffectors
commands
feedback
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Field of Dreams
• If you build it, they will use it…right?
Field of Force Production
• Motor Performance
– Observable behavior/skill execution at a specific moment in time
• Motor Learning
– set of processes associated with practice leading to a relatively permanent change in the capability for responding. (Schmidt & Lee,1998)
• Relatively permanent change in motor behavior
• Inferred from repeated observations of performance
• Promoted through practice or experience
• Motor Adaptation
– modifying an already well-learned motor skill that occurs over a period of trial and- error practice when exposing the skill to a novel, perturbing context or environment (Martin, Keating et al. 1996).
• With sufficient practice adaptation becomes separate and discrete motor plan that can be called upon when conditions are met (motor learning).
Learning vs. Performance
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Task/Learner/Environment
Environment Task
Learner
• Performance improvement
• Consistency
• Persistence
• Adaptability
– change in movement characteristics
• Stability
– change in task conditions
Characteristics of Motor Learning
• Acquisition
• Consolidation
• Learning
• Retention
– Ability to perform skill following period of no practice
– Measures persistence
• Transfer
– Ability to perform skill in altered environmental contexts, altered
levels of arousal and with altered movement characteristics
– Measures stability and adaptability
Assessment of Learning
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Retention Test
Transfer Test
• Neural correlate of learning
– Change within synapses: more synaptic receptors and
neurotransmitter vesicles increase the post-synaptic response to
the same input.
– Dendritic Spine proliferation
– Change in the area of cortical somatotopic representation
Neuroplasticity
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• Repetition matters
– Amount of practice single most important variable impacting
learning (Schmidt & Lee, 2011)
• Task specificity matters
– Skill acquisition
Neuroplasticity
Stages of Learning
Early Middle Late
Fitts &
Posner
Cognitive
• Attention/cognition-
heavy
• Trial strategies
• Limit DOF
• Large errors
• Variable performance
• Fast progress
Associative
• Refine skills
• Less attention-
dependent
Autonomous
• Increase automaticity
• Fine tune for different contexts
• Able to dual task
• Manage task & body efficiency
Systems
Theory
Novice
• Inefficient
• Inflexible
• Limit DOF
Advanced
• Open up DOF
• More adaptable to
envt & task
changes
Expert
• Able to use all DOF
• More efficient, coordinated,
flexible
• Take advantage of biomechanics
Gentile Initial/Conscious
• Goals: understand
task goals & dynamics
• Start to recognize
relevant factors in
envt
Later/Non-conscious
• Optimize force production & timing
• More consistent, efficient & flexible
• Fixation for ‘closed skills’,
diversification for ‘open skills’
Overview
33
Skill Definitions & Motor Control• Skill Classification• Control Theories
• Neural Basis
• Motor Planning
The Goal!
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• A motor skill represents learned processes of motor control that produce a coordination of voluntary movements to achieve a goal.
Motor Skill Classification
• One Dimensional
– Fine/gross
– Discrete/serial/continuous
– Open/closed environment
Motor Skill Classification
Motor Skill Classification
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Motor Skill Classification
Self-paced
Fixed Environment
Highly Predictable
Closed Skill
Externally-paced
Changing Environment
Open Skill
• Focalization of awareness
• Capacity is limited but not fixed
• Capacity and demand change
– Task/context requirement
– Skill level of the performer
Attention
Attention
https://www.youtube.com/watch?v=vJG698U2Mvo
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• Bottom up
– Directed toward novel or highly familiar/meaningful stimuli
• Top down
– Specific intention or direction
Selective Attention
Selective Attention
Feeling of grip force
Feel of the full golf
swing
The back rim of the
golf hole
The entire green
narrow broad
external
internal
3 6 5 2 9 4 9 1 7 0 9 4
7 5 2 9 7 2 1 5 4 3 2 6
Memory
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How many single digits did you remember?
A. ≤ 4
B. 5-6
C. 7-8
D. 9-10
E. > 10
Memory
Memory
632 145 729 527
904 179 294 452
How many single digits did you remember?
A. ≤ 4
B. 5-6
C. 7-8
D. 9-10
E. > 10
Memory
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• 3 Systems
– Sensory Register
• Large capacity
• Short duration (250 ms)
– Working memory
• Small capacity (7 ± 2)
• Short duration 20-30 s
– Long-term memory
• Limitless capacity and duration
Memory
• decision making
• comparisons
• problem solving
• interactive workspace
Memory
Sensory
Register
Working
memory
Long-term
memory
Selective
attention Rehearsal
• Implicit (How)– Procedural
• Declarative (What)– Episodic
– Semantic
• Is declarative memory is essential for motor skill learning?
Memory
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• Demonstration
• Instructions
• Feedback
• Practice Organization
• Practice Distribution
• Mental Practice
• Focus of Attention
• Enhanced Expectancies/Motivation
• Autonomy
Optimizing Motor Learning
• Demonstration
• Instructions
• Feedback
• Practice Organization
• Practice Distribution
• Mental Practice
• Focus of Attention
• Enhanced Expectancies/Motivation
• Autonomy
Optimizing Motor Learning
Demonstration
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• Skilled/perfect demonstration or unskilled/peer?
• How could we do this with our runner?
Demonstration
• Medial collapse in running
Movement Dysfunction
Willy et. al. Clin Biomechanics 2012
• Skilled/perfect demonstration
– Allows learning of invariant features of task
• Unskilled/peer demonstration
– Allows for identification of movement errors and facilitates
problem-solving
– Enhanced self-efficacy from “like” model
Demonstration
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• Intrinsic
– Available from sensory input
• Extrinsic/augmented
– Information from external source to supplement intrinsic
feedback
Feedback
• Essential
– When task-intrinsic feedback is not available or unidentifiable
• Unnecessary
– when task-intrinsic feedback sufficient/redundant
• Enhances
– During performance plateau or with new, complex coordination,
or if enhances motivation
• Hinders
– If individual becomes over-dependent, exceeds attention
capacity, diminishes motivation or promotes performance over
learning
Augmented Feedback
• Type– Knowledge of results (KR) – often apparent and redundant– Knowledge of performance (KP)– most helpful
• Timing– Concurrent vs terminal
• Concurrent often improves performance during practice but not on retention/transfer test
• Gap between performance and terminal feedback can allow for greater problem-solving of movement errors
• Frequency– Continuous
– Faded
– Bandwidth– Learner-regulated
Feedback
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• Impact of feedback frequency on learning
Retention Test
• Dobkin BH, Plummer-D'Amato P, Elashoff R, Lee J. International randomized clinical trial, stroke inpatient rehabilitation with reinforcement of walking speed
(SIRROWS), improves outcomes. Neurorehabilitation and neural repair. 2010;24(3):235-242
• Quantitative terminal feedback provided on gait speed vs no feedback (n=179)
• Reinforcement provided vs no reinforcement
– “Very good! You walked that in (number of) seconds.”
• “This is better by (number of) seconds”
• “This shows you are holding your own”
• “I believe that you will soon be able to walk a bit faster.”
• Treatment group walked significantly faster at discharge
– Walking speed at discharge (.91 v .72 m/s, p = .01) (21% difference between groups equal at admission)
– Walking speed at 3 months post-discharge (p = .03)
Feedback
• “Forcing the learner to actively develop problem-solving strategies independently of the guidance provided by…the therapist is actually beneficial for motor learning.” Carolee Winstein, PTJ 1991
Feedback
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• Variability of practice
– Contextual Interference (CI)
– Variable practice promotes adaptability
– Continuous search for task solutions
– Enhances capability to select appropriate parameters for context
Practice Organization
• Contextual Interference (CI)
– Practice performance disruption from performing multiple skills
or variations
• Blocked/constant practice
– Low CI
– Better for performance
• Random/variable practice
– High CI
– Better for retention and learning
Practice Organization
• UE prosthetic training; Weeks, Wallace, and Anderson (2003)
Practice Organization
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Practice Organization
• 3 Tasks:
• Pipe transfer
• Nut off hook
• Electrical Plug
• 2 days acquisition
• Blocked vs random
• Retention
• congruent vs incongruent
retention of blocked or
random
• Transfer 3 new Tasks:
• Sphere transfer
• Simulated feeding
• Padlock Opening
Weeks et al. 2003b
• Influence of previous experience on performing a new skill or skill in new context
Skill Transfer
Which might provide the most successful transfer to independent bicycling?
Push Bike
Training Wheels
Skill Transfer
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• Similar movements foster positive transfer.
• Different movements in similar environments foster negative transfer.
Skill Transfer
• Medial collapse in running
Movement Dysfunction
Willy et. al. Clin Biomechanics 2012
• Is all running the same?
– Uphill
– Downhill
– On level
– On treadmill
– Overground
• Will strength gained in one task transfer to use of strength in another task?
Transfer and Practice Organization
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Medial Collapse
• The effect of a hip strengthening program on mechanics during
running and during a single leg squat Willy RW, Davis IS. J Orthop
Sports Phys Ther. 2011 Sep;41(9):625-32.
– 20 female runners with excessive hip adduction – uninjured
– 6-week intensive hip strengthening program
– Last 4 weeks: functional strength training
Skill Transfer and Task Specificity
• The effect of a hip strengthening program on mechanics during
running and during a single leg squat Willy RW, Davis IS. J Orthop Sports
Phys Ther. 2011 Sep;41(9):625-32.
– Significant 23% improvement in hip strength
– Significant improvement in single leg squat hip mechanics (Hip ABD, hip
IR, contralateral pelvic drop)
– No change in gait kinematics during running
• Demonstration
• Instructions
• Feedback
• Practice Organization
• Practice Distribution
• Mental Practice
• Focus of Attention
• Enhanced Expectancies/Motivation
• Autonomy
Optimizing Motor Learning
10/20/2017
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OPTIMAL Theory
• Internal focus
– Attention on body movements
• External focus
– Attention on effects of movements on the environment
Attentional Focus
Instructions that direct an individuals’ attention to the effects of their movements on the environment inducing an ‘external’ focus of attention, are more effective for learning than instructions that direct attention to the movements themselves, inducing an ‘internal’ focus
Internal or External
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Tasks– Balance
– Golf– Soccer kicks– Football kicks
– Volleyball serves– Dart throwing– Tennis
– Basketball free throws– Rowing– Swimming
– Weight lifting– Agility– Sprint
– Force production– Vertical jump– Playing musical instruments
External Focus
Skill Level– Novice
– Expert
Age Groups– Children
– Young adults
– Older people
Disabilities– Parkinson disease
– Stroke
– Injuries
– Intellectual disability
• Internal focus: “Focus on the swing of your arms”
• External focus: “Focus on the swing of the club”
External Focus
• Goal was to push with 30% of maximum force
• Provided with under/over on each trial with verbal feedback
– Internal focus: “push with the muscle of your calf”
– External focus: “push against the platform”
External Focus
K. R. Lohse, D. E. Sherwood, & A. F. Healy, 2011
10/20/2017
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External Focus
• Wulf G, Chiviacowsky S, & Lewthwaite R. Altering mindset can enhance motor learning in older adults. Psychology and Aging. 2012;27:14-21.
Enhanced Expectancies/Motivation
• Intervention: “Active people like you, with your experience, usually do very well on this task.”
• Control
• Time spent in balance
• Palmer K, Chiviacowsky S, Wulf G. Enhanced expectancies facilitate golf putting. Psychology of Sport and Exercise. 2016;22(Supplement C):229-
232.
Enhanced Expectancies/Motivation
10/20/2017
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• Palmer K, Chiviacowsky S, Wulf G. Enhanced expectancies facilitate golf putting. Psychology of Sport and Exercise. 2016;22(Supplement C):229-
232.
Enhanced Expectancies/Motivation
• Back to the stabilometer– Chiviacowsky S, Wulf G, Lewthwaite R, & Campos T. Motor learning
benefits of self-controlled practice in persons with Parkinson’s Disease. Gait & Posture. 2012; 35: 601–605.
Autonomy
• The Renoir Effect– Wulf G, Freitas HE, & Tandy RD. Choosing to exercise more: Small
choices can increase exercise engagement. Psychology of Sport and Exercise, 2014;15:268-271.
– Self-determined and selection of second task to perform
– Yoked
Autonomy
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Putting It All Together
• Willy RW, Scholz JP, Davis IS. Mirror gait retraining for the treatment of patellofemoral pain in female runners. Clin Biomech. 2012;27(10):1045-
1051.
Putting It All Together
Interventions
• Shown abnormal mechanics via baseline video (demo)
• Taught to activate glutes by ABD/ER against wall
• “Increase distance between knees”
• “point kneecaps straight ahead”
• Maladaptations: widening stance and toeing out
• Faded feedback
• No running outside of PT (CI)
Putting It All Together
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Putting It All Together
Medial Collapse
• Chiviacowsky, S., Wulf, G., & Lewthwaite, R. (2012). Self-controlled learning: the importance of protecting perceptions of competence. Frontiers in Psychology, 3, 458. doi:https://dx.doi.org/10.3389/fpsyg.2012.00458
• Dobkin, B. H., Plummer-D'Amato, P., Elashoff, R., & Lee, J. (2010). International randomized clinical trial, stroke inpatient rehabilitation with reinforcement of walking speed (SIRROWS), improves outcomes. Neurorehabil Neural Repair, 24(3), 235-242. doi:10.1177/1545968309357558
• Haggard, P., & Wing, A. (1997). On the hand transport component of prehensile movements. J Mot Behav, 29(3), 282-287. doi:10.1080/00222899709600842
• Lewthwaite, R., Chiviacowsky, S., Drews, R., & Wulf, G. (2015). Choose to move: The motivational impact of autonomy support on motor learning. Psychonomic Bulletin & Review, 22(5), 1383-1388. doi:https://dx.doi.org/10.3758/s13423-015-0814-7
• Lohse, K. R. (2012). The influence of attention on learning and performance: pre-movement time and accuracy in an isometric force production task. Hum Mov Sci, 31(1), 12-25. doi:10.1016/j.humov.2011.06.001
• Lohse, K. R., Sherwood, D. E., & Healy, A. F. (2011). Neuromuscular effects of shifting the focus of attention in a simple force production task. J Mot Behav, 43(2), 173-184. doi:10.1080/00222895.2011.555436
• Nijs, J., Meeus, M., Cagnie, B., Roussel, N. A., Dolphens, M., Van Oosterwijck, J., & Danneels, L. (2014). A Modern Neuroscience Approach to Chronic Spinal Pain: Combining Pain Neuroscience Education With Cognition-Targeted Motor Control Training. Physical Therapy, 94(5), 730-738. doi:10.2522/ptj.20130258
• Palmer, K., Chiviacowsky, S., & Wulf, G. (2016). Enhanced expectancies facilitate golf putting. Psychology of Sport and Exercise, 22(Supplement C), 229-232. doi:https://doi.org/10.1016/j.psychsport.2015.08.009
• Willy, R. W., & Davis, I. S. (2011). The effect of a hip-strengthening program on mechanics during running and during a single-leg squat. Journal of Orthopaedic & Sports Physical Therapy, 41(9), 625-632. doi:https://dx.doi.org/10.2519/jospt.2011.3470
• Willy, R. W., Scholz, J. P., & Davis, I. S. (2012). Mirror gait retraining for the treatment of patellofemoral pain in female runners. Clinical Biomechanics, 27(10), 1045-1051. doi:https://dx.doi.org/10.1016/j.clinbiomech.2012.07.011
• Winstein, C. J., & Schmidt, R. A. (1990). Reduced frequency of knowledge of results enhances motor skill learning. Journal of Experimental Psychology: Learning, Memory, and Cognition, 16(4), 677-691. doi:10.1037/0278-7393.16.4.677
• Wulf, G., & Lewthwaite, R. (2016). Optimizing performance through intrinsic motivation and attention for learning: The OPTIMAL theory of motor learning. Psychonomic Bulletin & Review, 23(5), 1382-1414. doi:10.3758/s13423-015-0999-9
References