Motor Control Flashcards
What is motor control and why is it important for therapists to study?
Motor control is the ability to regulate or direct the mechanisms essential to movement. It is crucial for therapists to study because they frequently work with patients who have motor control issues, helping them retrain functional movement.
How do task constraints influence the neural organisation of movement? Give an example.
Task constraints influence neural organisation by dictating the type of movement required. For example, walking on a smooth, flat surface versus a rocky, uneven surface will place different demands on the nervous system, leading to different movement patterns.
Describe two ways to classify movement tasks and provide examples of each.
Movement tasks can be classified as discrete (having a clear beginning and end, like kicking a ball) or continuous (with an arbitrary endpoint determined by the performer, like walking). Another classification is based on stability, with tasks like standing being more stable than tasks like standing while lifting a heavy load.
Explain the difference between regulatory and non-regulatory features in the environment, using examples.
Regulatory features of the environment shape the movement itself, requiring the movement to conform to them to achieve the task goal (e.g., the size of a cup to be grasped). Non-regulatory features may affect performance but don’t require the movement to conform to them (e.g., background noise).
What are the key limitations of the reflex theory of motor control?
Limitations of reflex theory include: It struggles to explain voluntary and spontaneous movements, movements without sensory stimuli, and fast, sequential movements. It also doesn’t account for the variability of responses to the same stimulus and the ability to perform novel movements.
Describe the hierarchical theory of motor control and explain how current concepts have modified the original idea.
Hierarchical theory posits that higher levels of the CNS control lower levels, with reflexes governed by lower levels being inhibited by higher centres. While acknowledging hierarchical elements, current concepts recognise that each level can influence others depending on the task, and that reflexes are just one aspect of motor control.
How does the idea of a central motor pattern differ from a reflex?
A central motor pattern, or motor program, is a pre-structured set of movement commands that can be activated by either sensory stimuli or central processes. Unlike a reflex, which requires a specific stimulus to trigger a response, a central motor pattern can be initiated internally and is more flexible.
What is the degrees of freedom problem, and how did Bernstein propose that the nervous system solves this problem?
The degrees of freedom problem refers to the vast number of independent joints and muscles that the nervous system must coordinate to produce fluid movement. Bernstein suggested that the nervous system simplifies control by activating muscle synergies—groups of muscles constrained to act together as a unit.
Explain the concept of attractor states and how they relate to the stability of movement patterns.
Attractor states are preferred, stable patterns of movement that the system naturally gravitates towards. The depth of the “attractor well” reflects the stability of the pattern, with deep wells representing highly stable patterns resistant to change and shallow wells indicating unstable, easily altered patterns.
How does the ecological theory of motor control differ from other theories, and what are its key concepts?
Ecological theory emphasises the role of the environment in shaping movement, focusing on how individuals perceive and utilise information from the environment to guide their actions. Key concepts include affordances (opportunities for action offered by the environment) and invariants (consistent features of the environment that provide information for perception).
