L09: Motor Control- Role Of Motor Cortex And Spinal Reflexes

Question 1

What are the 2 types of motor descending pathways

Answer 1

Lateral

Ventromedial

Question 2

What is the lateral motor pathways involved in

Answer 2

Voluntary control of movement

Question 3

What is the ventromedial pathway involved in

Answer 3

Unconscious movement e.g standing up without thinking about it

Question 4

What does the sensory consequence of movement feed to from the spinal cord

Answer 4

Brainstem

Thalamus

Question 5

What does the thalamus feed into

Answer 5

The cerebral cortex

Question 6

What does the primary motor cortex fed to

Answer 6

Directly to the spinal cord
Or
To the spinal cord via the brainstem

Question 7

When basal ganglia and cerebellum receive info form the cerebral cortex where do they feed back to

Answer 7

Cerebral cortex

Question 8

What are the 3 types of movements

Answer 8

Reflex
Rhythmic motor patterns
Voluntary

Question 9

What is the reflex for

Answer 9

Protection

Question 10

Where are reflexes generated

Answer 10

In the spinal cord

Question 11

What are rhythmic motor patterns

Answer 11

Combination of reflex and voluntary movement

Question 12

What is voluntary movement

Answer 12

Purposeful movement

Question 13

What are lower motor neurones known as

Answer 13

Alpha motor neurones

Question 14

What do alpha motor neurones do

Answer 14

Make muscle contraction

Question 15

What 3 things control the lower motor nerurones

Answer 15

Sensory input
Spinal interneurones
Upper motor neurone

Question 16

How can movement be generated without the need of higher centres

Answer 16

Circuit within the spinal cord that is driven by sensory outputs

Question 17

What structures are controlled by the lateral motor neurones

Answer 17

Distal features such as fingers of hand and feet

Question 18

What are lateral motoneurone involved in

Answer 18

Fine motor

Question 19

Which structures are innervated by the medial motoneurone

Answer 19

Axial structures such as trunk and muscles

Proximal structures such as elbow and knee

Question 20

What is the medial motorneurones involved in

Answer 20

Posture

Question 21

Therefore what are lateral pathways involved in

Answer 21

Voluntary movement of distal muscles flexors

Question 22

Therefore what are ventromedial pathway involved in

Answer 22

Posture by proximal/axial muscles extensors

Question 23

What are the 2 tracts in the spinal cord involved in the lateral pathways

Answer 23

Corticospinal tract

Rubrospinal tract

Question 24

What are the 4 tracts involved in the ventromedial pathway in the spinal cord

Answer 24

Vestibulospinal tract
Tectospinal tract
Pontine reticulospinal tract
Medullary reticulospinal tract

Question 25

Where does the corticospinal tract start

Answer 25

In the motor cortex

Question 26

Where floes the rubrospinal tract start

Answer 26

Red nucleus of the midbrain

Question 27

Which areas of the motor cortex are axons of the corticospinal tract from

Answer 27

Areas 4 and 6 of the cortex

Question 28

Where does the corticopsinal tract decussate

Answer 28

Pyramidal decussation

Question 29

What structures does the corticospinal tract innervate

Answer 29

Distal muscles such as fingers

Question 30

What motoneurone does corticospinal tract innervate

Answer 30

The alpha motor neurones

Question 31

Where does the rubrospinal tract decussate

Answer 31

Straight after originating form the red nucleus

Question 32

If there are lesions to the lateral pathway i.e corticospinal tract and rubrospinal tract what is affected

Answer 32

Voluntary movement

Question 33

Is posture affected if lateral pathways are damaged

Answer 33

No because the ventromedial tracts are in damaged

Question 34

If the lesion is selective corticospinal tract can the patient cover

Answer 34

Yes because the rubrospinal tract can compensate apart from the fine digit control

Question 35

Where does all tracts of the ventromedial that originate from

Answer 35

Brainstem nuclei

Question 36

What structures does ventromedial tracts control

Answer 36

Proximal and axial for posture/body position

Question 37

What are the 4 pathways in the ventromedial pathways view as

Answer 37

In pair

Question 38

What are the 2 pairs of the ventromedial pathways

Answer 38

1) Pontine reticulospinal and medulla reticulospinal tract | 2) vestibulospinal and tectopsinal tract

Question 39

Which nuclei does the pontine reticulospinal and medulla reticulo spinal tract originate from

Answer 39

Reticular nuclei

Question 40

Where is the reticular nuclei/reticular formation for the pontine reticulospinal tract located

Answer 40

In the pons

Question 41

Where is the reticular nuclei/ reticular formation for the medullary reticulospinal tract located

Answer 41

Medulla

Question 42

What is the role of the pontine reticulo spinal tract

Answer 42

Enhance anti gravity reflexes of the spinal cord by facilitating leg extensors to maintain a standing position

Question 43

What is the role of the medullar reticulospinal tract

Answer 43

Opposing effect to pontine reticulospinal tract it allows voluntary control by freeing antigravity muscles from reflex

Question 44

Which nuclei does the vestibulospinal tract originate form

Answer 44

Vestibular nucleus in the medulla

Question 45

Which nuclei does the tectospinal tract originate from

Answer 45

Superioir colliculus in the midbrain

Question 46

What is the role of the vestibulospinal tract

Answer 46

Relays gravitational sensory info from the inner ear and maintain head and neck position as the body moves

Question 47

What is the role of the tectospinal tract

Answer 47

Relays sensory info from the retina and visual cortex and orientates head and eyes to a visual stimulus

Question 48

Give an example when the tectospinal tract is acitve

Answer 48

When you head a loud noise you turn your head to that side

Question 49

What is the area 4 of the cortex

Answer 49

Primary motor cortex (M1)

Question 50

What does area 6 in the cortex consist of

Answer 50

Pre motor area | Supplementary motor area

Question 51

What is area 4 (primary motor cortex) involved in

Answer 51

Controlling fine motor for distal muscles

Question 52

What is area 6 of pre motor area in cortex involved in

Answer 52

Controlling proximal muscles for posture and balance

Question 53

What is area 6 (supplementary motor area) involved in

Answer 53

Planning initiation and bimanual coordination and connects across to the other side providing biannual co-ordination

Question 54

What does 50% of the primary motor cortex have

Answer 54

Axons of the corticospinal tract

Question 55

What are the features of neurones in the primary motor cortex

Answer 55

Pyramidal type

Question 56

What may damage to the upper motor neurones by due to

Answer 56

Stoke | Tumour

Question 57

What does damage to the upper motor neurones lead to

Answer 57

Muscle weakness Spacitity due to increased muscle tone and hyperflexia Damage to contralateral side

Question 58

Does the vestibulospinal tract decussate

Answer 58

No

Question 59

Is corticospinal tract ipsilateral or contralateral

Answer 59

Contralateral

Question 60

Is the rubrospinal tract ipsilateral or contralateral

Answer 60

Contralateral

Question 61

Is the pontine/ medullary reticulo spinal tract ipsilateral or contralateral

Answer 61

Ipsilateral

Question 62

Is the vestibulospinal tract ipsilateral or contralateral

Answer 62

Ipsilateral

Question 63

Is the tectospinal tract ipsilateral or contralateral

Answer 63

Contralateral