Complexity Of Human Movement Flashcards
What are the major functional systems of the brain?
Sensory
Motor
Autonomic
&
High order functions: motivation memory, attention, cognition and executive
Reflex Theory
Stereotypical response to a specific stimulus; chaining
Chaining
Stimulus triggers a reflex response
Limitations of Reflex Theory
Absence of stimuli
Fast movements
Multiple responses
Novel movements
Hierarchical Theory
Control is from top to bottom; higher level exerts control
Limitations of the hierarchical theory
Can’t explain absense of stimuli
Stereotyped response
Doesn’t explain bottom up behaviors
Doesn’t explain novel movements
What is the Motor Program Theory?
Motor Control is not reactive;Movements may elicit by a sensory stimulus or intrinsically by a central process without afferent stimuli
What is the key point of the motor program theory?
Central motor program; exists in CNS, activated externally (outside stimulus) or centrally (voluntary or involuntary movement)
What did the motor program theory lead to?
Body-weight supported gait training; litegait & lokomat
Limitations of the Motor Program Theory
Storage problem
Does not explain musculoskeletal and environmental variation in motor task performance
Dynamical Systems Theory
Considers how the individual moves in their environmental
what is degrees of freedom?
Tasks can be completed in multiple ways; lots of possible movements at a joint
What is distributed control?
System work together cooperatively and produced movement through self organization; NOT hierarchical
What are synergies?
is a pattern of co-activation of muscles recruited by a single neural command signal; reduces computational load of nervous system
Music notes is compared to what?
Individual muscle action
Music melodies is compared to what?
Muscle synergies
Symphonies is compared to?
Complete actions
What is self-organization?
System parts come together, its elements behave in ordered way without specific commands
What two parameters can affect function?
Movement speed
Task goal
What fixes the degrees of freedom?
Synergies; reduces the computational load which provide us the most effective way to complete a task
What is the Ecological Theory?
Focus on how actions enable us to interact with the environment; relies on perception
What does the Ecological Theory emphasize?
Active Exploration
Which theory is correct?
No theory answers all; important to recognize the elements of individual, the task and the environment when considering movement
What do tasks require?
Stability
Mobility
Manipulation
What is feedforward?
Plan before execution; fast goal directed actions
ex: throwing a dart, pick up jug of water, performing a sit to stand
What is feedback?
Compares plan to result and enables correction; more engaged slower continuous movement
Ex: sudden perturbation when sitting or standing, driving along a curvy path
What is the perception Action Contiuum?
Ongoing cycle of steps we take to complete a task
What two stages of the perception action continuum are an example of perception?
Sensing and Perceiving
What two stages of the perception action continuum are an example of cognition?
Interpreting, Conceptualizing and planning
What two stages of the perception action continuum are an example of action?
Activating and execution
What are the two types of feedback?
Knowledge of performance
Knowledge of Results
What is knowledge of performance?
How a task was performed
What is knowledge of results?
Whether the task was completed successfully
