Brain Control of Movement

Question 1

What do lateral pathways control?

Answer 1

Voluntary movements of distal movements

Question 2

What do ventromedial pathways control?

Answer 2

Posture

Locomotion

Question 3

What is the main tract involved in the lateral pathways?

Answer 3

Corticospinal tract

Question 4

What areas of the brain does the CST originate from?

Answer 4

Areas 4 and 6 of frontal motor cortex (rest is somatosensory)

Question 5

Where does the CST decussate?

Answer 5

Medulla/spinal cord junction

Question 6

Where do CST axons synapse?

Answer 6

Ventral horn motor neurones and interneurones

Question 7

Where does the rubrospinal tract start?

Answer 7

Red nucleus of midbrain

Question 8

What is the result of lesions involving the CST and RST?

Answer 8

Loss of fine movements of arms and hands

Question 9

What is the result of lesions involving the CST?

Answer 9

Loss of fine movements, functions reappear after a few months

Question 10

What is the function of the vestibulospinal tract?

Answer 10

Stabilizes head and neck

Question 11

What is the function of the tectospinal tract?

Answer 11

Ensures eyes remain stable as body moves

Question 12

What are the 2 ventromedial pathways that control posture and locomotion?

Answer 12

Vestibulospinal tract

Tectospinal tract

Question 13

What are the ventromedial pathways that control trunk and antigravity muscles?

Answer 13

Pontine and medullary reticulospinal tracts

Question 14

Where do the pontine and medullary reticulospinal tracts originate?

Answer 14

Brainstem

Question 15

What is the function of the PRT and MRT?

Answer 15

Maintain balance and body position

Question 16

Where is the primary motor cortex located?

Answer 16

Precentral gyrus

Question 17

What are the somatotopically organised motor maps found in area 6?

Answer 17

Premotor area (PMA) 
Supplementary motor area (SMA)

Question 18

What is the function of the SMA?

Answer 18

Innervates distal motor units directly

Question 19

What is the function of the PMA?

Answer 19

Connects reticulospinal neurones innervating proximal motor units

Question 20

What creates a mental image of body?

Answer 20

Somatosensory, proprioceptive, and visual inputs to posterior parietal cortex

Question 21

Where are decisions made about what actions/movements to take?

Answer 21

Prefrontal and parietal cortex

Question 22

Where do axons from the prefrontal and parietal cortex converge?

Answer 22

Area 6

Question 23

What happens at the area where the prefrontal and parietal cortex converge?

Answer 23

Signals encoding what actions are desired are converted into how the action will be carried out.