Control of Movement 2

Question 1

What is motor equivalence?

Answer 1

Multiple ways to perform a movement to achieve the same goal

Question 2

What is required to stimulate the premotor areas?

Answer 2

Stronger and more prolonged stimuli

Question 3

What is the function of the premotor areas?

Answer 3

Involved in complex movements
Postural changes in preparation for movement
Intent to move in response to stimuli
Memory and learning of complex movements

Question 4

What effect does removal of the primary motor area have on the premotor areas and what can be concluded from this?

Answer 4

If the primary motor area is destroyed, stimulation of the premotor has no effect
Which implies the the principal actions of the premotor area are mediated through the primary motor cortex

Question 5

What defect occurs when the premotor areas are damaged?

Answer 5

Apraxias

Question 6

What is the function of the parietal cortex?

Answer 6

Integrates info from other areas of the brain to focus attention on relevant targget or spatial relationships of objects of interests

Question 7

What are the inputs into the parietal cortex?

Answer 7

Somatic sensory
Vestibular 
Premotor
Visual
Limbic

Question 8

What determines the force of a movement?

Answer 8

Impulse frequency

Question 9

What controls the direction of a movement?

Answer 9

Coordination of activation of motor neurones involved in different angles of movement

Question 10

What are the inputs into the corticospinal system?

Answer 10

Sensory receptors
Cerebellum
Basal ganglia

Question 11

Where do neurones in the corticospinal tracts originate from?

Answer 11

Primary motor cortex

Premotor and association areas

Question 12

What happens to most of the neurones in the corticospinal tracts?

Answer 12

Decussate at the ventral pyramids in the medulla and form the lateral corticospinal tract that travels contralaterally

Question 13

What happens to 10% of neurones in the corticospinal tracts?

Answer 13

Remain ipsilateral until they reach ventral root, where they innervate bilaterally and form the anterior corticospinal tracts

Question 14

What is the function of the lateral corticospinal tracts?

Answer 14

Control distal muscles contralaterally

Provide collaterals that geed into the brainstem nuclei to facilitate predictive postural set

Question 15

What is the function of the anterior corticospinal tracts?

Answer 15

Control axial muscles bilaterally

Question 16

Where does the rubrospinal tract originate?

Answer 16

Red nucleus

Question 17

What is the function of the rubrospinal pathway?

Answer 17

Controls the flexor activity of the upper limbs

Question 18

What are inputs to rubrospinal pathway?

Answer 18

Cerebellum

Corticospinal collaterals

Question 19

Which artery supplies the internal capsule?

Answer 19

MCA

Question 20

Name 4 things that can cause injury to the corticospinal tracts

Answer 20

Trauma
Tumour
Demyelinating disease
Infarction

Question 21

What is pyramidal muscle weakness?

Answer 21

UL extensors

LL flexors

Question 22

How do lesions of the internal capsule affect tone?

Answer 22

Hypotonia followed by hypertonia

Question 23

Where do neurones die first in ALS?

Answer 23

Periphery, then move inwards

Question 24

Which functions are spared in ALS?

Answer 24

Ocular motility
Sacral PNS
Motor coordination
Intellectual