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Flashcards in Motor control Deck (44)
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1
Q

How can motor control be described?

A

Functional hierarchy with 3 levels

2
Q

What is high level motor control?

A

Strategy

3
Q

What is strategy?

A

The goal and movement best to achieve goal

4
Q

What controls high level motor control?

A

Association neocortex, basal ganglia

5
Q

What is middle level motor control?

A

Tactics

6
Q

What are tactics?

A

Sequence of events to achieve a goal smoothly and accurately

7
Q

What is involved in middle level motor function?

A

Motor cortex, cerebellum

8
Q

What is low level motor control?

A

Excecution

9
Q

What is execution?

A

Activation of neurones to generate movement

10
Q

What is involved in low level motor control?

A

Brainstem

Spinal cord

11
Q

How is the brain connected to the spinal cord?

A

Lateral and ventromedial pathways

12
Q

What are the lateral pathways connecting the brain to the spinal cord?

A

Corticospinal and rubrospinal tracts

13
Q

What is controlled in the lateral pathways?

A

Voluntary movements of distal muscles

14
Q

Where does the corticospinal tract originate?

A

Areas 4 and 6 in frontal motor cortex and somatosensory

15
Q

What is the pathway of the corticospinal tract?

A

At spinal cord junction, tract crosses over

Axons synapse with motor neurones to control muscles

16
Q

Where does the rubrospinal tract originate?

A

Midbrain

17
Q

What do lesions of the corticospinal and rubrospinal tracts cause?

A

Loss of fine movements of hands and arms

Cannot move any part of upper limbs independently

18
Q

What do the ventromedial pathways control?

A

2 control posture and locomotion

2 control trunk and antigravity muscles

19
Q

What are the 2 pathways that control posture and locomotion?

A

Vestibulospinal and tectospinal tracts

20
Q

What does the vestibulospinal tract do?

A

Stabilises head and neck

21
Q

What does the tectospinal tract do>

A

Ensures eyes remain stable as body moves

22
Q

What are the 2 pathways that control trunk and antigravity muscles?

A

Pontine and medullary recticulospinal tracts

23
Q

Where do the pontine and medullary reticulospinal tracts originate?

A

Brainstem

24
Q

How do the pontine and medullary reticulospinal tracts work?

A

Use sensory information about balance, body position and vision

25
Q

What do voluntary movements require?

A

Inputs from motor cortex via lateral pathways

26
Q

How are skilled movements carried out?

A

Upper motor neurones from the cerebra cortex travel down lower motor neurones in the lateral spinal cord to control distal limb muscles

27
Q

How is posture and balance maintained?

A

Upper motor neurones from brainstem travel down lower motor neurones in the anterior medial spinal cord to control axial and proximal limb muscles

28
Q

What is area 4?

A

Primary motor cortex in pre central gyrus

29
Q

Where do premotor areas lie?

A

Anterior to central gyrus

30
Q

What is area 6?

A

Premotor area, connecting reticulospinal neurones and supplementary motor area

31
Q

What is the function of area 6?

A

Drive complex motor movements by connecting the innervation of proximal and distal motor units

32
Q

Where are decisions about actions and movements made?

A

Prefrontal and parietal cortexes

33
Q

Where does information about the position of the body and the action to be taken converge?

A

Area 6

34
Q

When do neurones in the cortical premotor area fire APs?

A

Before a movement, then increasing and continuing throughout the action

35
Q

When do neurones in area 6 fire APs?

A

When movement is made or imagined, or view someone else making a movement

36
Q

How is a population vector produced?

A

Responses of all neurones, which have different preferred directions, are combined

37
Q

What in the brain initiates feedwaryd adjustments?

A

Brainstem reticular foramen nuclei

38
Q

What are feedforward adjustments used for?

A

Stabilise posture

39
Q

What initiates feedback messages to the brain and what do they cause?

A

Change in body position

Stabilise posture

40
Q

Where do feedback messages travel from and to?

A

From brainstem vestibular nuclei to spinal cord motor neurones

41
Q

What does cortical damage cause?

A

Immediate flaccidity of contralateral muscles

42
Q

What does deprivation of cortical inputs to the spinal circuits cause?

A

Spinal shock and hypotonia

43
Q

How is function regained after damage to descending pathways?

A

Spared connections strength and new connections form

44
Q

What is the function of the basal ganglia?

A

Select and initiate voluntary movements