Week 13 Flashcards
(91 cards)
What are the 3 motor control theories?
- Reflex theories
- Historical theories (motor program theory)
- Dynamical/Ecological theories
(dynamical systems theory)
Whose work is the reflex theory based off of?
Sir Charles Sherrington
What are 2 basic assumptions of the reflex theory?
- reflexes are fundamental building blocks of all movement
* events in EN served as stimulus for action
In the reflex theory, complex behaviors result from?
chaining of reflexes
• individual is a passive recipient of externally-produced sensory input that excites motor systems
In the reflex theory: sensory –> _______–> ____________
sensory –> motor –> sensory (feedback)
monkey unilateral UE deafferentation (DRG cut) - lost mvmt. / went unchallenged for over 60 years
Is the reflex theory closed or open looped?
closed-loop in nature
List some of the reflex theories limitations:
Can’t explain:
- spontanteous or voluntary movements
- fast sequential movements (e.g. typing)
- reflexes can be modulated
- a single stimulus can trigger various responses - novel movements can be carried out
- Taub (1980) - deafferented monkeys
In contrast to the reflex theory, hierarchical theory assumes that all aspects of movement planning and execution are:
responsibility of one or more cortical centers representing highest command level within CNS
Is the hierarchical theory top-down or bottom-up?
top-down
In the hierarchical theory, motor control emerges from reflexes nested within:
hierarchically organized level in CNS
In the hierarchical theory:
• Higher centers always in control of ____________________.
• higher centers inhibit _________________________.
• Reflexes control by lower centers dominate movement only when _________________________.
- Higher centers always in control of LOWER CENTERS.
- higher centers inhibit REFLEXES CONTROLLED BY LOWER BRAIN CENTERS.
- Reflexes control by lower centers dominate movement only when HIGHER CENTERS ARE DAMAGED.
(Hierarchal theory) Neuromaturational theory of development, brain determines ________ behavior
infant
In the hierarchal theory, the cortex controls the postural reflex development of ___________________ and motor development of __________________.
In the hierarchal theory, the cortex controls the postural reflex development of EQUILIBRIUM REACTIONS and motor development of BIPEDAL FUNCTION.
In the hierarchal theory, the midbrain controls the postural reflex development of ___________________ and motor development of __________________.
In the hierarchal theory, the midbrain controls the postural reflex development of RIGHTING REACTIONS and motor development of QUADRUPEDAL FUNCTION.
In the hierarchal theory, the brainstem / spinal cord controls the postural reflex development of ___________________ and motor development of __________________.
In the hierarchal theory, the brainstem / spinal cord controls the postural reflex development of PRIMATIVE REFLEX and motor development of APEDAL FUNCTION.
List the limitations of the Hierarchical theory:
- can’t explain dominance of reflex behavior in certain adult situations (flexor withdrawl)
- EN and other non-CNS factors can affect infant movement (infant stepping reflex)
What are the current opinions on the hierarchical models?
- each level of motor system can act on other levels
* reflexes are only one of many motor control processes
Influence of Hierarchical theory on treatment paradigms: “When the influence of higher centers is temporarily or permanently interfered with, _______________________________________.”
normal reflexes become exaggerated and so called pathological reflexes appear
Influence of Hierarchical theory on treatment paradigms: “The release of motor responses integrated at lower level from restraining, influences of higher center, especially that of the cortex, leads to _____________________________.”
abnormal postural reflex activity
Motor program theory (hierarchical) =
detailed instructions are specified by the CNS to carry out the entire movement.
What are 2 key features of the motor program theory (hierarchical)
- Existence of Generalized Motor Programs
2. Existence of motor memory Schemas
What does the generalized motor program do?
organize, initiates, and carries out intended actions
(Motor program theory) proposed that every movement does not require:
a seperate motor program (command from executive is more general)
(motor program theory) introduced the concept of _____________________.
generalized motor program