Motor control - Introduction Flashcards
What are the 3 levels of motor control?
high
middle
low
What strucures are associated with high level motor control?
association neocortex
basal ganglia
What are the strucures associtaed wih middle level motor control?
motor cortex
cerebellum
What structures are associated with low level motor control?
brain stem
spinal cord
What do the lateral pathways control?
control voluntary movements
What do the ventromedial pathways control?
control posture and locomotion
A = ventromedial pathways
B = lateral pathways
Name the tracts in the lateral pathways?
corticospinal tracts
rubrospinal tract
Name the tracts in the ventromedial pathways?
tectospinal tract
vestibulospinal tract
pontine reticulospinal tract
medullary reticulospinal tract
What controls the lateral pathways?
under direct cortical control
What controls the ventromedial pathways?
under brain stem control
What areas are the motor cortex?
area 4 and 6
Where do 2/3 of the CST come rom?
frontal motor cortex areas 4 and 6
the rest are from the somatosensory
what does the somatosensory area help with motor?
e.g. a diver, tells you where you are in space, you need sensory input to help with motor function
visual, joint angle input within space an time
What does the right motor cortex control?
left side of body
Where do the CST axons synapse?
in the ventral horn and interneurons to control muscles
Where do the RST start?
starts in the red nucleus of midbrain
What happens when there is a lesion to the CST and the RST?
lose fine motor movements of arms and hands. cant move shoulders, elbows, wrist and fingers independently
You need both
What does the RST take inputs from?
cortical areas, same as CST
What happens in solely a CST lesion?
same limb deficits but after a few months functions reappear.
taken over by RST, because if now lesion RST - lose restored functions
What type of neurones are present in the motor cortex and project via the CST?
LARGE PYRAMIDAL
The interneurones excite muscles but at the same time have to do what?
inhibit the opposing muscle
inhibits pools of antagonist motorneurones
if you want to flex the elbow, you will excite flexor muscles and inhibit extensor muscles
What tracts control voluntary movements?
CST
RST
