MC 1 (foundations, feedback and movement control) Flashcards
What is a motor behaviour?
a motor activity (action) carried out through muscle contraction
What is a motor task?
the objective to be achieved through a motor behaviour
What’s the difference between an action and a movement?
action = aim movement = way of achieving aim
What is motor equivalence?
the same action carried out by execution of different (sequences of) movements
e.g. different ways to pick up a bag
What is motor adaptability?
the ability to accomplish the same motor task by adjusting the motor behaviour to different conditions
What is motor control?
the ability to maintain and change posture and movement in a variety of contexts
What’s the difference between an open and closed loop system?
open loop doesn’t monitor the environment, closed loop does.
closed loop is therefore able to alter the input based on the output
What is feedback control?
correction based on the difference between the observed and desired measure
How does the proportional feedback control law differ from feedback control?
the control variable is proportional to the error
What are the two branches of the NERVOUS SYSTEM and their components?
CNS: brain + spinal cord (all contain grey and white matter)
-protected by bones
PNS: nerves (axons) and ganglia (neurons)
- not protected by bones
Two main components of the Cerebrum?
> cerebral cortex
> basal ganglia
What are the 4 lobes of the cerebral cortex and their functions?
> frontal
temporal
parietal
occipital
sub-division isn’t functional but each lobe receives input from different sensory systems and is involved in different types of processes
Where is the motor cortex and what are its functions?
an area in the frontal lobe of the cerebral cortex.
fundamental for voluntary motor control and the planning/deciding of actions
What are the 3 sub-divisions of the motor cortex?
> PRE-MOTOR CORTEX: organisation of movements before initiation
PRIMARY MOTOR CORTEX: initiation and coordination of voluntary movements
SUPPLEMENTARY MOTOR AREA: prep and control of sequential movements
The role of the basal ganglia?
controlling voluntary movement
What makes up the basal ganglia?
set of subcortical neural nuclei
- striatum (caudate nucleus + putamen)
- globus pallidus
- substantia nigra
- subthalamic nucleus
Give a short overview of the direct pathway through the basal ganglia and the output the the thalamus and cerebral cortex
substantia nigra
(stimulates)
putamen
(inhibits)
globus pallidus int
(less inhibition of)
thalamus
(more stimulation of)
cerebral cortexWhat is the resultant effect of the direct pathway on the cerebral cortex activity?
Activation of cerebral cortex
more movement
Give a short overview of the indirect pathway through the basal ganglia and the output the the thalamus and cerebral cortex
substantia nigra
(inhibits)
putamen
(less inhibition of)
globus pallidus ext
(less inhibition of)
subthalamic nucleus
(more excitation of)
globus pallidus int
(more inhibition of)
thalamus
(less stimulation of)
cerebral cortexWhat is the resultant effect of the indirect pathway on the cerebral cortex activity?
Inhibits cerebral cortex
less movement
What is Parkinson’s disease?
death of neurons in the substantia nigra
What effect does Parkinson’s have on the cerebral cortex and movement?
Reduced cerebral cortex activation.
- difficulty initiating movement
- slowness of voluntary contractions
- shuffling gait
- tremor at rest
What is Huntington’s disease?
lessions in the subthalamic nucleus
What effect does Huntington’s have on the cerebral cortex and movement?
increased cerebral cortex activation.
- excess of involuntary movement
Where is the cerebellum located and what is its role?
located at the back of the pons (brainstem) - fundamental role in execution of smooth and accurate movement - concerned w/ motor coordination, posture and balance
How is the cerebellum involved in the correction of movement?
it receives input from the motor cortex (movement plan) and sensory systems (movement performance) and compares in order to correct and adjust movements
Aim of the direct pathway?
‘loosen the leash on the thalamus’
Greater activity of thalamus, and in turn, cerebral cortex.
Aim of the indirect pathway?
‘tighten the leash on the thalamus’
less activity of thalamus, and in turn, cerebral cortex
Think of changing from running to walking.
