Lecture 12 Motor Control 1

Question 1

What area is the Primary Motor Cortex

Answer 1

Area 4 (M1)

Question 2

What area is the Supplementary Motor Cortex

Answer 2

Area 6 (SMA &PMA)

Question 3

What area is the Posterior Parietal Cortex

Answer 3

Area 5 and 7

Question 4

How many levels are involved in voluntary movements

Answer 4

3

Question 5

Name the levels and functions involved in voluntary movement

Answer 5

High- Strategy- Association Neocortex, Basal ganglion
Middle- Tactis- Motor cortex, cerebellum
Low-Execution- Brainstem and spinal cord

Question 6

How is the brain connected to the spinal cord

Answer 6

Lateral pathway and Ventromedial pathways

Question 7

What is the Lateral pathway

Answer 7

Controls voluntary movements of distal muscles

Question 8

Where do 2/3rds of the CST originate from

Answer 8

Areas 4 & 6

Question 9

What is the Rubrospinal Tract

Answer 9

A much smaller tract that starts n the red nucleus of the midbrain and receives input from the same cortical areas as the CST

Question 10

What is the consequence of lesions to the CST and the RST

Answer 10

Fine movements of arms and hands are lost- cannot move shoulders, elbows, wrist and fingers independently

Question 11

What is the consequence of a CST lesion alone

Answer 11

Same deficits seen as before but after a few months functions appear as RST takes over

Question 12

What do large pyramidal neurones in the motor cortex do

Answer 12

Project via CST
Monosynaptically excite pools of agonist muscles
Inhibit pools of antagonist motoneurons

Question 13

What is the function of Ventromedial pathways

Answer 13

Control posture and locomotion

Under brainstem control

Question 14

What 2 ventromedial pathways control posture and locomotion

Answer 14

Vestibulospinal tract

Tectospinal tract

Question 15

How does the vestibulospinal tract control posture

Answer 15

Stabilises head and neck

Question 16

How does the tectospinal tract control posture and locomotion

Answer 16

Ensures eyes remain stable as body moves

Question 17

Where does the vestibulospinal tract travel through

Answer 17

Vetsibula nucleus in th medulla

Question 18

Where does the tectospinal tract travel through

Answer 18

The super colliculus in the midbrain

Question 19

What ventromedial pathways control trunk and antigravity muscles

Answer 19

Pontine and medullary reticulospinal tracts

Question 20

Where do the pontine and medullary reticulospinal tracts originate

Answer 20

Brain stem

Question 21

How do the pontine and medullary reticulospinal tracts reflexly maintain balance and body position

Answer 21

Uses sensory information about balance, body position and vision

Question 22

What doe the pontine and medullary reticulospinal tracts innervate

Answer 22

Trunk and antigravity muscles in limbs

Question 23

Define Somatotopic

Answer 23

the orderly and specific relation between particular body regions (as a hand or the tongue) and corresponding motor areas of the brain

Question 24

Medial tracts from brainstem control__

Answer 24

Posture, balance and orienting mechanism

Question 25

Lateral tracts from cortex control___

Answer 25

Precise skilled voluntary movements

Question 26

What are the Primary Motor Cortex and Premotor Areas

Answer 26

Area 4

Area 6

Question 27

Areas of the cortex involved in panning and instructing voluntary movement

Answer 27

Area 6
Area 4
Area 5
Area 7

Question 28

Where does SMA innervate

Answer 28

Distal motor units

Question 29

Where does the PMA innervate

Answer 29

Connects with reticulosponal neurones innervating proximal motor units

Question 30

Microstimulation in specific area of primary motor cortex (area 4) elicits

Answer 30

(A) coordinated movements of hand and mouth or

(B) movements that bring hands into central space to inspect/manipulate objects.

Question 31

Mental image of body inspire is generated by what

Answer 31

Somatosensory, proprioceptive and visual inputs to posterior parietal cortex (area 5 and 7)

Question 32

What part of the brain are decisions taken

Answer 32

Pre-frontal and parietal cortex

Question 33

Axons from pre-frontal and parietal cortex converge where

Answer 33

Area 6 here signals encoding desired action are converted into how to carry them out