Motor Development: Motor Control and Motor Learning for Occupational Therapy
Foundations of Motor Control and Motor Learning
Motor Control Definition: The process of how an individual directs and regulates their movement.
Motor Learning Definition: The process of learning and refining motor skills over time. It is essentially the act of learning how to control your movement.
Clinical Presentations and Deficits
Deficits in motor control are commonly seen in several conditions, including cerebral palsy (CP), developmental coordination disorder (DCD), autism spectrum disorder (ASD), Down syndrome, sensory integration disorder, acquired brain injury (ABI), and various intellectual disabilities.
Muscle Tone: Clients may present with mild dysfunction in muscle tone.
Dysmetria: An inability to estimate distance, leading the client to overshoot or undershoot when reaching for objects.
Intention Tremors: These are tremors that occur specifically during attempted voluntary movement.
Limited Force Control: Difficulty with grading the amount of strength or energy required for a task.
Dysdiadochokinesia (Diadocopinesis): Difficulty with performing rapid changes of motion.
Poor Bilateral Motor Control: An inability to perform movements using both sides of the body simultaneously.
Coordination Deficits: Difficulty with fine and gross motor coordination, resulting in the inability to perform small or large movements in a smooth manner.
Balance and Equilibrium: Challenges maintaining stability during movement or while stationary.
Associated Reactions: Involuntary movements occurring in one part of the body while another part is being moved.
Example: A child focusing intensely on writing may exhibit involuntary tongue movements.
Example: A child tensing one arm while performing a task with the other arm.
Interaction Among Systems: Person, Task, and Environment
Occupational therapists (OTs) must consider the interaction between multiple systems when designing interventions. This is categorized into the person, the task, and the environment (context).
The Person: Includes internal factors such as:
Age and developmental stage.
Cognition.
Musculoskeletal system (e.g., strength, posture).
Sensory systems and integration.
Perception and discrimination abilities.
Social-emotional status (how they feel and think).
The Task: Refers to the nature and characteristics of the activity, including:
Is it simple or complex?
Is it big or small?
Specific requirements and constraints of the activity.
The Environment: The context in which performance occurs:
Physical Environment: The actual building or space.
Social Environment: Social pressures and presence of others (e.g., a child may perform differently alone versus in a classroom).
Cultural Environment: Family expectations for movement precision.
Temporal Environment: The developmental stage and age-appropriate expectations (e.g., clumsiness is tolerated in younger children but precision is expected in older children).
Virtual Environment: Engaging through digital platforms or video games.
Personal Environment: Personal factors required within a specific context.
Core Concepts: Grading and Failure
Making the Grade: Grading is the primary method for approaching pediatric motor control. OTs seek to find the "just-right challenge"—an activity that is challenging but possible, leading to success.
The Role of Failure: Learning is not strictly about constant success. The adapted mantra is "Practice and failure makes perfect."
Critical Challenge: Challenge is necessary for progress. Within a session, a client can fail multiple times and learn from those mistakes, which contributes to overall success in motor learning.
Theoretical Frameworks
Dynamic Systems Theory: Suggests that the interaction among systems (Person, Task, Environment) is essential to adaptive movement control. This theory mirrors the PEO (Person-Environment-Occupation) model.
Ecological Theory: Emphasizes the interaction specifically between the person and their environment, focusing on perception and the physical context. The task is not the central focal point.
Example: A staircase is considered "climbable" if the child's biomechanics (musculoskeletal function) allow them to navigate the physical environment of the stairs.
Application: Motor Control Principles
Whole Learning: Engaging the client in the entire activity rather than isolated steps (e.g., crafts, dress-up, cooking, themed games).
Variability: Incorporating a variety of tasks that require the same motor movement. This can be achieved by:
Varying the object used.
Varying object placement.
Varying the task requirements or environmental context.
Problem Solving and Error-Based Learning: Varying degrees of difficulty and allowing the child to figure it out. Mistakes are permitted so the client can self-correct and learn.
Application: Motor Learning Principles
Meaningful Activities: Activities must be purposeful, interesting to the client, and demonstrate pleasure or willingness to engage.
Transfer of Learning (Generalization): Applying skills learned in one setting to new situations or natural contexts.
Example: Moving from maneuvering a wheelchair in a clinic obstacle course to maneuvering through a school hallway.
Grading and Adapting Table:
Simple Activities (e.g., placing a ball in a bucket) vs. Complex Activities (e.g., mini-golf).
Single Step vs. Multi-step sequences.
Discrete Movement (e.g., picking up an object) vs. Continuous Movement (e.g., walking).
Unimanual (one hand) vs. Bimanual (two hands).
Stationary (holding an object) vs. Moving (catching a ball).
Modeling and Demonstration: Showing the client how to perform a task before, during, or after engagement.
Best Practice: Model slowly and minimize verbal feedback during the demonstration.
Verbal Instruction: Short, clear instructions (approximately to words) that emphasize key aspects of movement.
Practice Protocols and Types
Whole vs. Part Practice:
Whole Practice: Best for simple, shorter skills (e.g., baking premade cookies).
Part Practice: Preferred for complex skills that take longer. Isolated parts must be "natural units" of the activity (e.g., chopping vegetables as a step toward cooking a meal).
Blocked Practice (Mass Practice): Repeating one skill or similar movements over and over with limited variety (e.g., putting pegs in a board). It is less motivating and harder to generalize but useful for early-stage learning of simple tasks.
Distributed Practice: Practicing skills in various ways by repeating different but related tasks.
Fine Motor Example: Tearing paper (neat pincer grasp) -> Gluing paper (in-hand manipulation) -> Coloring (tripod grasp).
Variable Practice (Random Practice): Practicing a task in the natural context requiring various movements and positions. This is the best method for transfer of learning and generalization (e.g., playing with marbles scattered across a floor).
Mental Practice: Preparing to perform a task by using imagery. This is most effective when combined with physical practice for better carryover.
Progression Mnemonic and Strategy
Key Line: "MC (Motor Control) deficits make blocking diss very hard."
Implementation Sequence: Blocked Practice -> Distributed Practice -> Variable Practice.
Start with Blocked if the client is really struggling and needs things simple.
Progress to Distributed, and finally to Variable once they show success.
Questions & Discussion
Case Study 1: Toddler with Hemiplegic CP
Question: A toddler with hemiplegic cerebral palsy is in early intervention to improve play skills. The OT is using a motor-based activity to teach the child how to incorporate the hemiplegic upper extremity into play sequences. Which option is best?
Options Analysis:
A) Assist the caregiver in obtaining switch-activated toys. (Incorrect: Limits independence/interaction).
B) Provide hand-over-hand assist to the right extremity. (Incorrect: Best for lack of initiation or neglect, not functional integration).
C) Utilize the affected hand to stabilize the trunk while having the child reach into a bin of toys. (Correct: Encourages the hemiplegic hand to act as a "helper" or stabilizer, making play more independent and functional).
Case Study 2: Student Climbing Play Equipment
Question: A student is having difficulty climbing on play equipment. The playground has many different climbing ladders of various inclines. Which activity would be best when using the motor learning approach?
Options Analysis:
A) Use different equipment to create similar angles in the school clinic. (Incorrect: Moving away from the natural context).
B) Engage the student on the playground equipment to problem solve barriers. (Correct: Utilizes the natural environment and practice/repetition as per motor learning principles).
C) Ask the student to imagine what it would feel like to climb. (Incorrect: This is specific to a "mental imagery" approach, not the primary motor learning choice in this context).