Motor Control Theories: A Comprehensive Analysis
Theory Overview:
Motor Control Theories
Reflex Theory
Reflections are the building blocks of complex behavior, working together or in sequence to achieve a common purpose. The conception of a reflex requires three structures: a receiver, a conductive pathway, and an effector.
Limitations: Reflexes cannot be considered the basic unit of behavior; a sequence of reflexes does not explain the ability to produce movement.
Clinical Implications (CI): A patient’s motor behavior should be interpreted in terms of the absence or presence of reflexes.
Hierarchical Theory
The brain has higher, middle, and lower levels of control, corresponding to higher association areas, motor cortex, and spinal levels of motor function.
Limitations: This theory cannot explain the predominance of reflex behavior in normal adults in certain situations.
CI: Many doctors use the organization of reflex abnormalities to explain motor disturbances in neurological patients.
Motor Programming Theory
The term “motor program” can identify a central pattern generator—a specific neural circuit (e.g., the one that produces a cat’s walk).
Limitations: Motor programs cannot be viewed as the sole determinant of action.
CI: Doctors can go beyond a reflex-based explanation of motor control disorders. Comments have been expanded to include abnormal movement resulting from alterations in central pattern generators or higher-level motor programs.
Systems Theory
This theory explains the systems that move the body (external and internal forces).
Limitations: It does not address the organism’s interaction with the environment.
CI: Evaluation and treatment should focus not only on weaknesses of particular systems contributing to motor control but also on interactions between multiple systems.
Dynamic Action Theory
This model suggests that underlying movement is the result of the interaction of physical and neural components.
Limitations: It assumes the nervous system plays a totally insignificant role and that the relationship between the animal’s physical system and its environment mainly determines its behavior.
CI: As doctors understand more about the physical and dynamic properties of the human body, they can use this knowledge to help patients regain motor control.
Ecological Theory
This theory emphasizes the nervous system’s role as a sensory-motor system that responds to environmental variables. It views the nervous system as a system that receives and actively explores the environment to suit its own purposes.
Limitations: It tends to give less emphasis to the organization and function of the nervous system underlying such interaction.
CI: This theory describes the individual as an active explorer of the environment.
Which Theory is Best?
The best theory combines elements of all presented theories—a complete, or integrated, theory recognizing familiar elements of motor control and leaving room for new knowledge. Any current theory is incomplete because there must always be room for review and incorporation of new information.
Motor Learning and Recovery of Function
Learning and Recovery
Learning: Acquisition and/or modification of motor behavior.
Recovery of Function: Acquisition of lost motor behavior.
Relationship Between Learning and Performance
Learning: Permanent change in motor behavior.
Performance: Temporary change in motor behavior.
Factors Contributing to Learning
Feedback: Intrinsic (from the individual’s own sensorimotor system) and extrinsic (reinforcement from outside sources).
Knowledge of Results: Understanding the outcome of a movement.
Conditions of Practice: Mass vs. part practice; constant vs. variable practice; random vs. blocked practice; whole vs. part training; transfer; mental practice.
Recovery of Function
Function: Complex activity of the whole body to perform a goal-directed behavior.
Recovery: Restoration of lost function after injury.
Recovery vs. Compensation
Compensation: Behavioral substitution; adopting alternative behavioral strategies to complete an activity (reaching through an alternative process).
Recovery: Achieving function through the original process.
Factors Affecting Recovery of Function
Age; task characteristics; pre-injury neuroprotective factors; post-injury factors (drugs, neurotrophic factors, exercise, training).