Motor Control And Motor Learning

MOTOR CONTROL AND MOTOR LEARNING APPROACH General Concepts: Incorporates theories of motor control and motor learning. Used with combinations with task-related learning. Consideration is given to both intrinsic and environmental constraints. MOTOR CONTROL “An area of study dealing with the understanding of the neural, physical, and behavioral aspects of movement. Stages of Movement Control

Stimulus

Within the CNS Stimulus Identification Response Selection Sensing Interpreting Perceiving Planning Memory contact Deciding

Response Programming Translating Structuring Initiating response Sensitive to: Sensitive to: Sensitive to: Clarity No. of alternatives Complexity Intensity Compatibility of Duration Pattern of complexity stimulus & Compatibility of the stimulus response. Of responses

Movement Output

MOTOR PLAN An idea or plan for purposeful movement that is made up of component motor programs. MOTOR PROGRAM An abstract representation that, when initiated, results in the production of coordinated movement sequence. FEEDFORWARD The sending of signals in advance of movement to ready the system, allows for anticipatory adjustments in postural activity. FEEDBACK Response-produced information received during or after the movement, in used to monitor output for corrective actions. MOTOR LEARNING “A set of internal processes associated with practice or experience leading to relatively permanent changes in the capability for skilled behavior. School of Physical Therapy-Therapeutic Exercises 3 (O’Sullivan & Schmitz: Physical Rehabilitation-Assessment & th Treatment, 5 ed.)| helenjudymaban09

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Measures of motor learning: 1. Performance: determine overall quality of performance, level of automaticity, level of effort, speed of decision making. 2. Retention: provides a better measure of learning. Ability of the learner to demonstrate the skill over time and after the period of no practice (retention interval). 3. Generalizability: The ability to apply a learned skill to the learning of other similar tasks (transfer test). 4. Resistance to contextual change: This is the adaptability required to perform a motor task in altered environmental situations. STAGES OF MOTOR LEARNING Provides a useful framework for describing the learning process and for organizing training strategies. (table). STRATEGIES TO ENHANCE MOTOR LEARNING (table) FEEDBACK INTRINSIC: sensory information normally acquired during performance of a task. EXTRINSIC AUGMENTED: externally presented feedback that is added to that normally acquired during task performance. Concurrent feedback: given during the task performance. Terminal feedback: given at the end of task performance. KNOWLEDGE OF RESULTS: augmented feedback about the end result of overall outcome of the movement. KNOWLEDGE OF PERFORMANCE: augmented feedback about the nature or quality of the movement pattern. Varied feedback Schedules: 1. Summed feedback: given after a set number of trials. 2. Faded feedback: feedback given at first after every trial and then less frequently. 3. Bandwidth feedback: feedback given only when performance is outside a given error range 4. Delayed feedback: feedback given after a brief time delay can also be beneficial in allowing the learner a brief time for introspection and self-assessment. PRACTICE The second major influence on motor learning. The more the practice, the greater the learning (ENGRAM).

School of Physical Therapy-Therapeutic Exercises 3 (O’Sullivan & Schmitz: Physical Rehabilitation-Assessment & th Treatment, 5 ed.)| helenjudymaban09

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MASSED versus DISTRIBUTED PRACTICE MASSED PRACTICE: refers to a sequence of practice and rest times in which the rest time is much less than the practice time. DISTRIBUTED PRACTICE: refers to spaced practice intervals in which the practice time is equal to or less than the rest time. BLOCKED versus RANDOM PRACTICE BLOCKED PRACTICE: refers to a practice sequence organized around one task performed repeatedly, uninterrupted by practice of any other task; repetitive practice. RANDOM PRACTICE: refers to a practice sequence in which a variety of tasks are ordered randomly across trials. PRACTICE ORDER: refers to the sequence in which tasks are practiced. 1. Blocked order: refers to the repeated practice of a task or group of tasks in order. 2. Serial order: refers to a predictable and repeating order. 3. Random order: refers to a non-repeating and non-predictable order. MENTAL PRACTICE Is a practice strategy in which performance of the motor task is imagined or visualized without overt physical practice. Has consistently been found to facilitate the acquisition of motor skills. It should be considered for patients who fatigue easily and are unable to sustain physical practice. It is also effective in alleviating anxiety associated with initial practice by previewing the upcoming movement experience. Generally contraindicated in patients with profound cognitive, communication, and/or perceptual deficits. VARIABLE PRACTICE: practice of varied motor skills in which the performer is required to make rapid modifications of the skill in order to match the demands of the task. SERIAL PRACTICE: practice of a group or class of motor skills in serial or predictable order. TRANSFER OF LEARNING The effects of having previous practice of a skill or skills upon the learning of a new skill or upon performance in a new context; transfer may be either positive (assisting learning) or negative (hindering learning). Refers to the gain (or loss) in the capability of task performance. School of Physical Therapy-Therapeutic Exercises 3 (O’Sullivan & Schmitz: Physical Rehabilitation-Assessment & th Treatment, 5 ed.)| helenjudymaban09

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PART-WHOLE TRANSFER: a learning technique in which a complex motor task is broken down into its component or subordinate parts for separate practice before practice of the integrated whole. BILATERAL TRANSFER: learning can be promoted through practice using contralateral extremities. TASK-RELATED TRAINING APPROACH General Concepts. a. Emphasis is on focusing use of the affected body segments/limbs using task-related experiences and training. 1. Patients practice important functional tasks essential to independence. 2. Patients practice tasks in appropriate and safe environments; focus is on anticipated environments for daily function. b. Patients practice under therapist’s supervision and independently. 1. Therapists provide assistance through guided movement and verbal cueing. 2. Therapists serve as motor learning coaches, encouraging correct performance. 3. Exercise/activity logs can help organize the patient’s self-monitored practice. 4. Repetition and extensive practice are required. c. Promotes use-dependent cortical reorganization (neural plasticity) and recovery. d. Prevents learned non-use of the affected body segments/extremities. CONSTRAINT-INDUCED MOVEMENT THERAPY (CI) A task-oriented training approach for patients recovering from stroke in which the unaffected UE is restrained with use of an arm sling and resting hand splint while training is focused on the affected UE. Uses massed practice (up to 6 hours/day) with repetitive training of functional tasks. Operant conditioning techniques are used to shape responses. BODY WEIGHT-SUPPORTED TREADMILL TRAINING (BWSTT) Task-oriented training approach in which the patient walks with assistance on a treadmill with body weight partially supported. Slow treadmill speeds (typically 0.01-2.25 m/s) and light support using an overhead harness (typically 30% of body weight to start) are used during initial practice; speeds are gradually increased and weight support is gradually reduced. One or two therapists provide manual assistance in stabilization of trunk/pelvis and in movement of the paretic limb. Progression is to over ground walking; body weight support can be used to start with progression is to no weight support.

School of Physical Therapy-Therapeutic Exercises 3 (O’Sullivan & Schmitz: Physical Rehabilitation-Assessment & th Treatment, 5 ed.)| helenjudymaban09

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COMPENSATORY TRAINING APPROACH General Concepts a. Indications: to offset or adapt to residual impairments and disabilities. b. Focus is on early resumption of functional independence with reliance on uninvolved segments for function. c. Changes are made in the patient’s overall approach to tasks. 1. Patient is made aware of movement deficiencies, alternate ways to accomplish tasks. 2. Patient relearns functional patterns and habitual ways of moving. 3. Patient practices functional skills in variety of environments. Issues with the compensation approach a. Focus on uninvolved segments to accomplish daily tasks may suppress recovery and contribute to learned nonuse of the impaired segments. b. Focus on task specific learning may lead to the development of splinter skills in patients with brain damage; skills cannot be easily generalized to other tasks or environmental situations. c. May be the only approach possible. 1. If no additional recovery is anticipated. 2. If severe motor deficits are present or if sensorimotor recovery has plateaued. 3. If patients exhibits extensive co-morbidities and poor health. Strategies a. Simplify activities. b. Establish a new functional pattern; identify key task elements, residual segments available for control of movements. c. Repeated practice; work toward consistency, efficiency. d. Energy conservation and activity pacing techniques are important to ensure completion of all daily movement requirements. e. Adapt environment to facilitate relearning of skills, ease of movement. 1. Simplify; set up for optimal performance. 2. Use environmental adaptations to enhance performance.

School of Physical Therapy-Therapeutic Exercises 3 (O’Sullivan & Schmitz: Physical Rehabilitation-Assessment & th Treatment, 5 ed.)| helenjudymaban09

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