Neural control of movement

Question 1

What are the 4 component parts of movement?

Answer 1

Lower motor neurons
Upper motor neurons
Cerebellum
Basal ganglia

Question 2

Where are lower motor neuron cell bodies located?

Answer 2

Ventral horn/ brainstem

Question 3

What do lower motor neurons innervate?

Answer 3

Striated muscles via NMJ

Question 4

Where are upper motor neuron cell bodies located?

Answer 4

Cortex/ brainstem

Question 5

Where do UMN synapse?

Answer 5

Interneurons or LMNs

Question 6

What 2 tracts do UMNs split into?

Answer 6

Pyramidal and non-pyramidal

Question 7

Where do pyramidal tracts arise from?

Answer 7

Motor cortex

Question 8

Function of pyramidal tracts

Answer 8

Planning, initiating and directing voluntary movements

Question 9

Where do extrapyramidal tracts arise from?

Answer 9

Brainstem

Question 10

Function of extrapyramidal tracts?

Answer 10

Postural control, navigation and antigravity

Question 11

Name 3 extrapyramial tracts

Answer 11

Rubrospinal, vestibulospinal and reticulospinal tracts

Question 12

2 general functions of the cerebellum and basal ganglia

Answer 12

Regulate activity of UMNs

Receive information from motor cortex and feed back to it

Question 13

Is cerebellum or basal ganglia inhibitory?

Answer 13

Basal ganglia

Question 14

Specific function of the cerebellum?

Answer 14

Coordinates complicated movements, acting as comparator or predictors of movements
Receives input from muscles and compared with intended signal for movement

Question 15

Function of vestibulo-cerebellum

Answer 15

Balance and posture

Question 16

Function of spino-cerebellum

Answer 16

Locomotion

Question 17

Function of cerebro-cerebellum

Answer 17

Skilled motor tasks

Question 18

What is the function of basal ganglia?

Answer 18

Initiate and maintain motor tasks

Question 19

Name the 5 basal ganglia

Answer 19

Caudate
Putamen
Globus Pallidus
Subthalmic nucleus
Substantia nigra

Question 20

What 3 main structure makes up the motor cortex

Answer 20

M1- primary motor cortex
PMA- premotor area
SMA- supplementary motor area

Question 21

Where does motor cortex feed into?

Answer 21

Pyramidal tract

Question 22

What makes up the association motor cortex?

Answer 22

PMA+SMA

Question 23

Result of damage to association motor cortex?

Answer 23

Apraxia- loss of ability to carry out familiar learned movements

Question 24

Function of primary motor cortex?

Answer 24

Voluntary control of movements via LMNs

Question 25

Function of premotor area?

Answer 25

Planning movements that involve external sensory cues and learned motor activies

Question 26

Function of supplementory motor area?

Answer 26

Planning movements that involved internal commands or cues

Question 27

Define tone

Answer 27

Resting level of contraction

Question 28

Symptoms of hypertonia

Answer 28

Spasticity and rigidity

Question 29

What causes spasticity

Answer 29

Loss of inhibition of gamma motor neurons.

Question 30

What tract is involved in causing spasticity

Answer 30

Pyramidal

Question 31

What causes rigidity

Answer 31

Loss of inhibition of alpha motor neurons

Question 32

What tract is involved in causing rigidity

Answer 32

Extrapyramidal

Question 33

What is hypotonia and what causes it

Answer 33

Flaccidity, damage to LMNs

Question 34

Function of rubrospinal tract?

Answer 34

Gross movements

Facilitates flexor movement

Question 35

Function of vestibulospinal and reticulospinal tracts?

Answer 35

Posture and balance

Question 36

5 functions of UMNs

Answer 36

1- excitation
2- inhibition
3- reflex modulation
4- efference copu
5- activation of other brainstem UMNs

Question 37

What is meant by efference copy?

Answer 37

Internal copy of an outflowing movement producing signal generated by motor system, enabling comparison of actual movement with desired movement

Question 38

Role of posterior parietal cortex in movement?

Answer 38

Decision to move and functional consequence of action

Question 39

Role of association motor cortex?

Answer 39

Plans to moves are stored until required

Question 40

Role of the primary motor cortex?

Answer 40

Instruction to move- activates descending pathways

Question 41

What happens if there is a signal mismatch detected by cerebellum

Answer 41

Uncoordinated movements

Question 42

How does brake theory describe role of basal ganglia?

Answer 42

To keep still- brakes on all movements except the reflexes that maintain upright posture
To move- apply a brake to some postural reflexes and release brake on voluntary

Question 43

How do antigravity muscles differ from other muscles?

Answer 43

More developed with greater tone

Question 44

What is a neuromuscular disorder?

Answer 44

Condition affecting one or more of the following: muscles, nerves, NMJs, motor or sensory cell body

Question 45

Describe organisation of the main upprt motor neuron pathways

Answer 45

Corticobulbar: originate from cerebral cortex motor area and goes to brainstem
Corticospinal: originate from cerebral cortex motor areas and goes to spinal cord
Vestibulospinal and reticulospinal: originates from brainstem and goes to spinal cord
Rubrospinal: same as above

Question 46

What makes up the ready, steady and go of motor cortex?

Answer 46

Ready: posterior parietal cortex (decision to move)
Steady: association motor cortex (sotres plan to move)
Go: primary motor cortex (activates descending pathways)

Question 47

What is the function of basal gangli?

Answer 47

Initiation and maintenance of motor action- decision making

Scale the strength and response, organise correct sequences of activity

Question 48

Sign of cerebellum damage?

Answer 48

Ataxis and hypotonia

Question 49

Sign of basal ganglia damage?

Answer 49

Hyper/hyopkinesia (slow or unwanted movements)

Question 50

Sign of association motor cortex

Answer 50

Apraxi