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1

what are the 3 levels of motor control hierarchy?

high
middle
low

2

what are the structures associated with high motor control?

association neocortex
basal ganglia

3

what are the structures associated with middle motor control?

motor cortex
cerebellum

4

what are the structures associated with low motor control?

brainstem
spinal cord

5

what do the lateral pathways of the spinal cord control?

voluntary movements of distal muscles - under direct cortical control

6

what do ventromedial pathways control?

posture and locomotion - under brain stem control

7

where does the corticospinal tract decussate?

medulla/spinal cord junction

8

how do CST axons control muscles?

they synapse on ventral horn motor neurones and interneurons

9

where does 2/3ds of the CST originate?

areas 4 and 6 of the frontal motor cortex - rest is somatosensory

10

where does the rubrospinal tract originate?

red nucleus of the midbrain

11

what happens if there are lesions in the CST and RST?

fine movements of the arms and hands lost.
unable to move shoulders, elbows, wrist and fingers independently

12

what happens if there is a lesion in the CST but not the RST?

fine movements initially lost but after a few months functions reapper because the RST takes over

13

what does the vestibulospinal tract do?

stabilizes head and neck

14

what does the tetospinal tract do?

ensures eyes remain stable as body moves

15

where do the pontine and medullary reticulospinal tracts originate?

brainstem

16

what sensory information do the pontine and medullary Reticulospinal tracts use?

balance
body position
vision

17

what is the function of the pontine and medullary reticulospinal tracts?

reflexly maintain balance and body position
innervate trunk and antigravity muscles in limbs

18

what does the motor cortex do when complex movement is required?

directly activates spinal motoneurones and frees them from reflex control by communicating via nuclei of ventromedial pathways

19

where do the medial tracts of white matter originate?

brainstem

20

where do the lateral tracts of white matter develop?

cortex

21

where in the brain is the primary motor cortex?

precentral gyrus

22

what does the cerebral cortex need to know in order to plan movement?

where the body is in space
where it wants to go
needs to select a plan to get there

23

what is the function of the supplementary motor area?

innervates distal motor units directly

24

what is the function of the premotor area?

connects reticulospinal neurones innervating proximal motor units

25

why is area 6 of the brain sometimes described as a "junction"?

it is where signals encoding what actions are desired are converted into how the actions will be carried out

26

what happens with regard to blood flow to the brain during practised voluntary finger movements?

blood flow increases in the following areas:
somatosensory
posterior parietal
prefrontal cortex
areas 6 and 4

27

if you were to "think" about making a movement, which area would be active?

area 6 but not area 4- area 4 is for "doing it"

28

what are the decision making neurones in command centres?

neurones in the premotor area

29

when are neurones in area 6 fired?

during movement
when movement is imagined
when you see others making a specific movement

30

how is the direction of movement decided?

neurone discharge is greatest in a preferred direction
each neurone has a preferred direction but responses of all neurons are combined to produce a population vector
overall movement direction is encoded by the integrated activity of all neurones