Motor Control Theories: Traditional vs. Contemporary Approaches

1. Traditional approaches to motor control a. Reflex-based, hierarchical, neurofacilitation or neurodevelopment approaches- NDT, PNF, Rood, Brunnstrom 2. Contemporary approaches to motor control a. Task-oriented approaches b. Dynamic Systems Theory c. Dynamical Systems Approach d. Occupational Therapy Task-Oriented Approach

Movement is task-specific and constrained by the environment.

The individual generates movement in order to accomplish a task of to meet the demands of the environment.

1. Functional tasks help organize motor behavior 2. Occupational performance emerges from the interaction of multiple systems that constitute the unique characteristics of the person and the environment 3. After CNS damage or other changes in personal or environmental systems, client's behavioral changes reflect attempts to achieve functional goals 4. Practice and active experimentation with varied strategies and in varied contexts are needed to find the optimal solution for a motor problem and to develop skill in performance

1. Conceptualization that movements are controlled by systems cooperating toward the production of movement but without central executive control (1, p. 187) 2. Argues that it implausible that the higher cortical centers contain millions of unique programs that tell each muscle what to do, with what force, with what duration and that these are learned by repetition (i.e., hierarchical model). 3. Instead, belief that the system doesn't have one control center to execute or modify movement but that systems cooperate together toward the production in movement without a central executive control. 4. Hierarchical systems basically the Sensory-Motor-Sensory feedback cycle results in numerous motor programs 5. And that movement is a result of the higher centers taking in the sensory input and dispensing the appropriate motor program to perform that movement

Preferred (but not-obligatory) pattern of behavior (i.e., movement pattern) that emerges from the interaction of a unique person with a particular task and environment (2)- 1. Help to conserve energy (think automatic actions) 2. Person typically has stable movement patterns or attractor states with some flexibility 3. However, in acute stages of recovery, one can show little stability in attractor states...therefore, task performance is not effective or efficient (5, p. 486)

1. A variable (i.e., control parameter) that acts as an agent to cause transition (i.e., phase shift) behavior from one preferred form to another form, thereby facilitating a reordering of behavior (2) 2. A variable whose change can shift a pattern of motor behavior into another pattern (1, p. 187) a. Person (e.g., pain can cause us to alter movement pattern) b. Environment (e.g., different writing utensil can cause us to alter movement pattern) CONTROL PARAMETER Environment - - Writing on paper vs writing on the board - Changing the type of writing utensil (pencil vs. paint brush) Person --- - Pain - that inhibits a usual movement pattern (back pain - lifting a box) DEGREES of FREEDOM

Child with delayed motor skills catches a ball with a scooping motion (attractor state). A goal of therapy is to improve motor skills and coordination (e.g., catching a ball with hands). Therapists applies control parameter (e.g., slowing of the throw, lighter ball, bigger ball) and assesses what degree of slowing or weight/size is needed to cause a phase shift (e.g., change from scooping motion to catching with hands) How long it takes to return to scooping motion after control parameters (e.g. weight, size, speed) are removed?

1. Body dimensions 2. Age 3. Gender 4. Activity level 5. Maturational 6. Cognitive 7. Affective (motivation) 8. Neuronal and non-neuronal changes since CNS damage

1. Consider the various movement patterns needed to place different objects on a shelf (physical) a. Size, weight, texture, space, etc. A. Other environmental constraints 1.Social (e.g., loading a different dishwasher) 2. Cultural (e.g., specific way of arranging items) 3. Temporal (e.g., in a rush) - Social (are you doing this with someone else, in your kitchen? Their kitchen? Cultural (is there a specific way of arranging items? Are their items that evoke meaning - ingredients of family recipe?) Temporal (in a rush? Preparing the ingredients later tonight?)

1. Factors that serve as major influences on occupational performance (can be personal or environmental). 2. Aim is to help individuals identify and use critical factors that support optimal performance and to determine the optimal value for producing the best performance outcome 3. Critical factors can be organic or environmental- Organic (e.g., strength, balance, visual-perception), Environmental (e.g., size or weight of object, position in space) 4. Critical factors change over time Note: Some systems are highly affected immediately after CNS damage while others systems are highly affected later.

Identify tasks that are meaningful and important to client's roles 2. Occupation-Based a. Describe the movements (attractor states) used for task performance- Determine whether movements are stable or in transition. Effective, efficient, safe? b. Analyze the characteristics of the tasks selected for treatment- Discrete, continuous, serial? Mobility, stability Open, closed? 3. Person and Environment a. Identify the personal and environmental factors that serve as major influences on occupational performance (critical factors) a. Personal factors, such as: Age, gender, maturation, Body dimensions, Neuronal and non-neuronal, Cognitive, affective b. Environmental factors, such as: Physical, social, cultural, etc. 4. Stability vs. Mobility a. Stability tasks (non-moving base of support) b. Mobility tasks (moving base of support) 5. Manipulation continuum a. Amount of UE involvement in the tasks (dexterity, speed, accuracy) Discrete vs. Continuous vs. Serial (5) Discrete tasks (Beginning and end) Frequent practice of the movement is required to learn and (sometimes to maintain) the skill at a high level Continuous tasks (No recognizable beginning and end) Generally retained even when there are periods when practice is not possible Serial tasks (Series of discrete movements)

1. Describe the movements (attractor states) used for task performance a. Determine whether movements are stable or in transition. b. Effective, efficient, safe? 2. Analyze the characteristics of the tasks selected for treatment a. Discrete, continuous, serial? b. Mobility, stability? c. Open, closed?

Identify the personal and environmental factors that serve as major influences on occupational performance (critical factors) 1. Personal factors, such as: a. Age, gender, maturation b. Body dimensions c. Neuronal and non-neuronal d. Cognitive, affective 2. Environmental factors, such as: a. Physical, social, cultural, etc.

1. Stability vs. Mobility a. Stability tasks (non-moving base of support) b. Mobility tasks (moving base of support) 2. Manipulation continuum a. Amount of UE involvement in the tasks (dexterity, speed, accuracy)

1. Discrete tasks (Beginning and end) a. Frequent practice of the movement is required to learn and (sometimes to maintain) the skill at a high level 2. Continuous tasks (No recognizable beginning and end) a. Generally retained even when there are periods when practice is not possible 3. Serial tasks (Series of discrete movements) -- Discrete: tying a shoe, hitting a baseball (position, load when ball leaves pitcher's hand, turn hips, pull with leading arm, watch ball until point of contact, maintain head position at point where contact occurred rather than watching your ball) Continuous: balancing (in general), walking Serial: hitting a baseball (position, load when ball leaves pitcher's hand, turn hips, pull with leading arm, watch ball until point of contact, maintain head position at point where contact occurred rather than watching your ball)

1. Closed tasks (stable and predictable environments) a. Example: Showering 2. Open tasks (changing and unpredictable environments) a. Often complex placing more demands on the person b. Example: Driving a car

1. Select and use functional tasks that are meaningful and important to client's roles 2. Anticipate how personal and environmental factors that influence occupational performance will or can change 3. Address critical factors (personal and environmental) to change occupational performance. Alter variables until the control parameter is identified as indicated when a shift (Phase shift) in motor behavior is observable 4. Treat neural and non-neural factors of the sensorimotor system that interfere with optimal occupational performance a. E.g., increase in muscle strength is related to improved functional performance in clients with hemiparesis (8) 5. Adapt the task or broader environment to promote optimal occupational performance a. Modify task initially so learner can succeed b. To alter movement patterns: Use varied size, length, or weight, Change speed or accuracy, Social reinforcement 6. Select and use functional tasks that are meaningful and important to client's roles 7. Anticipate how personal and environmental factors that influence occupational performance will or can change 8. Address critical factors (personal and environmental) to change occupational performance- Alter variables until the control parameter is identified as indicated when a shift (Phase shift) in motor behavior is observable Structure practice of the task to promote motor learning Random practice is better than blocked practice Random practice would be practicing a variety of closely related tasks within one session (e.g. varied dressing tasks) Blocked practice would be presenting a series of steps that must be practiced again and again in the same manner (e.g., donning/doffing shirt) NOTE: Performance may look worse with random practice vs. blocked practice; however, this is OK because the objective is to enhance motor learning and the capability for later performance

1. Use natural objects and environments a. Research shows that reaching tasks enriched with natural objects result in more efficient, direct, smooth and planned movements than reaching tasks without natural objects b. Rehabilitation environments should simulate real-life setting as much as possible

1. Treat neural and non-neural factors of the sensorimotor system that interfere with optimal occupational performance (8) a. E.g., increase in muscle strength is related to improved functional performance in clients with hemiparesis (8) 2. Adapt the task or broader environment to promote optimal occupational performance (8) a. Modify task initially so learner can succeed b. To alter movement patterns:Use varied size, length, or weight , Change speed or accuracy, Social reinforcement

Structure practice of the task to promote motor learning-Random practice is better than blocked practice 1. Random practice would be practicing a variety of closely related tasks within one session (e.g. varied dressing tasks) 2. Blocked practice would be presenting a series of steps that must be practiced again and again in the same manner (e.g., donning/doffing shirt) 3. NOTE: Performance may look worse with random practice vs. blocked practice; however, this is OK because the objective is to enhance motor learning and the capability for later performance -- Random practice: Putting of a jacket, putting on a jacket on doll, zipping the doll's jacket, zipping your own jacket Tracing letter "a" on sand paper, making circles on paper, looking for the letter "a" Blocked practice: Button shirt, unbutton...10 times Writing letter over and over

Structure practice of the task to promote motor learning- Use strategies to vary the context within a task 1. Manipulation of tasks dimensions a. Support surfaces b. Objects and equipment c. Task demands d. Required information 2. Varied context promote development of preferred movement patterns for specific contexts and flexibility in movement patterns for different contexts --- Easel, chalkboard, notebook, flat desk Pencil grip, crayon, cool marker, orthotic Write on line, write around a circle Change instructions, change desired outcomes.

Design practice sessions to fit the type of task and learning strategies A. Whole vs. Part Learning 1. Whole learning a. Generally preferred for continuous and discrete tasks b. Preferred for relatively simple tasks 2. Part learning a. Generally preferred for learning discrete components of serial task b. Preferred for complex tasks

Design practice sessions to fit the type of task and learning strategies A. Explicit vs. Implicit Learning 1. Explicit learning a. Requires conscious learning of rules for task performance 2. Implicit learning a. Requires learning how to do the task on an unconscious level b. Is facilitated by structuring the environment and practice of the task -- Explicit - following a recipe Implicit - dressing, grooming, 1. Often for individuals with motor control problems they are having to relearn a task previously learned and performed implicitly...making it structured can be helpful 2. Another point, giving the cues can trigger implicit memory/learning centers and yield better performance - (giving someone a shirt to put on without explicit instruction). 3. Dog example - reaching across midline with no context, pure movement focused---compared to petting a dog.

Provide feedback that facilitates motor learning. Feedback is the info received about performance while learning a new skill. A. Types of Feedback 1. Intrinsic Feedback a. Gathered through sensory avenues (e.g., vision and proprioception) b. Feedback is compared to learned reference of correct movement to detect errors and correct movement 2. Extrinsic Feedback a. Often verbal feedback to the learner about task success and performance B. Motor learning requires opportunities for self-assessment and self-correction. 1. How do therapists facilitate this process? 2. How do we halt or interfere with this process? 3. Does the type of feedback matter? Idea of what is absolutely necessary -- Yoga examples -- intrinsic (feedback from your senses) vs extrinsic feedback from the instructor. Often need to allow for delayed processing prior to giving extrinsic feedback.

1. Knowledge of results (information about the movement outcome...task success) a. What was the outcome? 2. Knowledge of the performance (information about the correctness of the movement pattern that the learner makes...task performance) a. How did the movement feel?

1. Research indicates that too much extrinsic feedback can be counter-productive to the individual's learning... a. If it interferes with their processing of intrinsic information about the movement skill or b. If it interferes with their developing error detection capability 2. For persons without motor problems: a. Research states that feedback should be less frequent, random or intermittent, faded over time, & given as summary information 3. However, when applied to individuals post stroke: a. Results have demonstrated improved performance consistency but not improved accuracy...more research needs to be done (8, p. 496)

Encourage experimentation with solutions to occupational performance problems (8) 1. Guidance learning a. Physically guiding the learner through the task to be learned b. Used at the outset of teaching a task to acquaint the performer with characteristics of the task to be learned 2. Discovery learning a. Trial and error learning by the learner b. May be less effective for acquisition of the skill c. But is more effective for later retention and transfer

Encourage experimentation with solutions to occupational performance problems- 1. Feedback should take the form of coaching the client during learning by: a. Directing the focus to the functional outcome b. Suggesting movements to try c. Recording progress d. Assisting with decision making with new challenges e. Provide manual guidance if necessary, but allow some elements to vary so that person can experiment with movement patterns f. Fade assistance provided through handling ASAP

1. Discover the optimal movement patterns for task performance 2. Achieve flexibility, efficiency, and effectiveness in task performance 3. Develop problem-solving skills in clients so they can identify their own solutions to occupational performance problems in home and community

1. Constraint of unaffected (or less affected) limb a. Using cast, splint, sling, mit, glove 2. Completion of one-handed activities using affected limb a. For specific period of time (hrs/day/week) b. Progressive task practice c. Provide assistance as necessary to complete task 3. Population: a. Persons with hemiplegia (e.g., stroke, TBI, CP)

1. Completion of bilateral activities using affected limb a. For specific period of time (hrs/day/week) b. Progressive task practice c. Provide assistance as necessary to complete task 2. Population: a. Persons with hemiplegia (e.g., stroke, TBI, CP)

1. Child-centered, goal-oriented approach 2. Involves a child-directed, problem-solving process (i.e., goal-plan-do-check) to carry out motor task 3. Emphasis is on guided discovery and use of cognitive strategy to effectively perform motor tasks 4. Therapists should refrain from identifying solutions or prompting child to perform task a certain way 5. Population: a. Children with DCD but being investigated for ASD and CP