Motor Pathways

Question 1

Give the 3 main groups of fibres.

Answer 1

Projection fibers. Association fibers. Commissural fibres.

Question 2

What do projection fibres connect?

Answer 2

Connect a lobe to other parts of the brain.

Question 3

What do association fibres do?

Answer 3

Connect regions within the same hemisphere.

Question 4

What do commissural fibres do?

Answer 4

Connect 2 hemispheres.

Question 5

What is the corpus callosum?

Answer 5

Thick nerve tract consisting of a flat bundle of commissural fibres.

Question 6

Give the role of descending nerve pathways.

Answer 6

Voluntary movement. Sensory driven reflex responses.

Question 7

Give 3 areas of the cortex.

Answer 7

Premotor cortex. Supplementary cortex. Primary motor cortex.

Question 8

What is the function of the premotor cortex?

Answer 8

Plan movement.

Question 9

What is the function of the supplementary cortex?

Answer 9

Strategize and achieve goal.

Question 10

What is the function of the primary motor cortex?

Answer 10

Activate spinal motor neurones and initiate movement.

Question 11

Give the 2 descending tracts of the primary motor cortex.

Answer 11

Corticospinal and corticobulbar.

Question 12

What two things does the corticobulbar connect?

Answer 12

Connects cortex and medulla oblongata.

Question 13

What cells make up the corticospinal tract?

Answer 13

Large Betz cells.

Question 14

Corticostriate (to basal ganglia) and corticothalamic (thalamus) go through what?

Answer 14

Corona radiata.

Question 15

Where is the most common site for strokes?

Answer 15

Internal capsule.

Question 16

What does the mid-brain coordinate?

Answer 16

Voluntary eye and head movements.

Question 17

What happens to the corticospinal tract at the medulla?

Answer 17

They crossover and bundle together.

Question 18

What are the two tracts of the pyramidal tracts?

Answer 18

Corticospinal and corticobulbar.

Question 19

Corticobulbar tract connects impulses between what?

Answer 19

Brain to the cranial nerves.

Question 20

Corticospinal tract connects impulses between what?

Answer 20

Brain to the spinal cord.

Question 21

What nerves control the muscles of the face and neck and are involved in facial expression, mastication, swallowing, and other functions.

Answer 21

Cranial nerves.

Question 22

What tract is involved with voluntary movement.

Answer 22

Corticospinal tract.

Question 23

Why are they named pyramid tracts?

Answer 23

Because they pass through the pyramids of the medulla oblongata.

Question 24

The tract going from the cortex to the pons is known as the…

Answer 24

Corticopontine tract.

Question 25

What is the function of lateral corticospinal tracts?

Answer 25

Skilled movements hands and feet.

Question 26

What is the function of anterior corticospinal tracts?

Answer 26

Innervate arms and neck

Question 27

Name 2 of the 4 extrapyramidal tracts.

Answer 27

Vestibulospinal, tectospinal, reticulospinal, rubospinal.

Question 28

What is the function of the vestibulospinal tract.

Answer 28

Control balance and posture.

Question 29

The extrapyramidal system centers on the modulation and regulation (indirect control) of which cells.

Answer 29

Anterior (ventral) horn

Question 30

What is the function of the tectospinal tract?

Answer 30

Head movements in response to visual/auditory signals.

Question 31

What is the function of the reticulospinal tract?

Answer 31

Mediates motor function, mediates autonomic function and pain pathway.

Question 32

What is the function of the rubrospinal tract?

Answer 32

Fine control hand movements. Locomotion.

Question 33

What is the difference between the pyramidal and extrapyramidal tracts?

Answer 33

Pyramidal tracts originate in the cerebral cortex, carrying motor fibres to the spinal cord and brain stem but extrapyramidal tracts originate in the brain stem, carrying motor fibres to the spinal cord. Pyramidal tracts are are responsible for the voluntary control of the musculature of the body and face but, extrapyramidal tracts are responsible for the involuntary and automatic control of all musculature, such as muscle tone, balance, posture and locomotion