PCB4843 Exam 4 - Questions with Correct Answers
(Verified Update)
100 questions with answers
Topic: PCB4843 Exam 4
1. basal ganglia
Answer: a set of subcortical structures that directs intentional movements
2. internal capsule
Answer: bundle of axons that transfers information to and from the cortex involved in
corticospinal tract
3. cerebral peduncle
Answer: midbrain area fibers that connect cortex to brainstem involved in corticospinal tract
4. medullary pyramids
Answer: triangular divisions within the medulla involved in corticospinal tract
5. red nucleus
Answer: a large nucleus of the midbrain that receives inputs from the motor cortex and
sends axons to motor neurons in the spinal cord involved in rubrospinal tract
6. vestibular nuclei
Answer: pons nuclei that receive information from the vestibular organs involved in
vestibulospinal tract
7. superior colliculus
Answer: midbrain, for visual reflexes and spatial orienting involved in tactospinal tract
8. pontine reticular formation
Answer: area of the pons with many nuclei involved in pontine reticulospinal tract
9. premotor area (PMA)
Answer: just in front of M1, lateral, for planning movements
10. supplementary motor area (SMA)
Answer: just in front of M1, medial, modulates the activity of the primary motor cortex
11. posterior parietal cortex (PPC)
Answer: combines input from sensory areas for higher-level functions
12. globus pallidus (GP)
Answer: subcortical structure part of basal ganglia, mediates movements, projects to VLo
13. ventral lateral nucleus (VLo)
Answer: in thalamus, controls motor information, projects to cortex
14. striatum (caudate nucleus + putamen)
Answer: subcortical structure part of basal ganglia, projects to GP
15. subthalamic nucleus (STN)
Answer: receives projection from cortex for the indirect pathway, part of basal ganglia
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, 16. substantia nigra (SN)
Answer: in midbrain, produces dopamine, can excite or inhibit striatum
17. somatic motor system
Answer: muscles + neurons that control muscles coordinates unconscious and conscious
movement
18. motor programs
Answer: circuits that evoke patterns of activity to coordinate movement
19. alpha motor neurons
Answer: directly trigger the generation of force by muscles
20. what drives alpha motor neurons
Answer: upper motor neurons in cortex and brainstem
21. hierarchy of motor processing (functions and brain areas of each level)
Answer: highest level: strategy/goal of movement (cortex, basal ganglia) middle level:
determining sequence of contractions (cortex, cerebellum) lowest level: execution to activate
motor and interneuron pools to generate movement (brainstem, spinal cord)
22. axons from brain to spinal cord descend along two categories of pathways (name
and location)
Answer: voluntary = lateral reflexive = ventromedial
23. list the two voluntary pathways
Answer: corticospinal and rubrospinal tracts
24. corticospinal tract path
Answer: cortex -> internal capsule -> cerebral peduncle -> medullary pyramid ->
decussates at medulla/spinal cord -> spinal cord
25. rubrospinal tract path
Answer: red nucleus in midbrain -> decussates immediately -> pons -> medulla -> spinal
cord receives inputs from similar motor areas as corticospinal tract
26. lesions to voluntary pathway
Answer: both lesions cause deficits in movement (slower, less precise, less accurate) but,
corticospinal tract lesions are less harmful as long as rubrospinal tract is in tact
27. list the four reflexive pathways and their functions
Answer: vestibulospinal (head turning) tectospinal (orienting to objects) pontine
reticulospinal (extensors in lower limbs/posture) medullary reticulospinal (inhibits excessive
reflex activity to maintain posture)
28. vestibulospinal tract pathway
Answer: vestibular system -> vestibular nucleus -> bilateral projection to spinal cord
29. tectospinal tract pathway
Answer: retina input -> superior colliculus -> decussates immediately -> spinal cord
30. pontine reticulospinal tract pathway
Answer: pontine reticular formation -> medullary reticular formation -> ipsilateral spinal
cord **no decussation
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(Verified Update)
100 questions with answers
Topic: PCB4843 Exam 4
1. basal ganglia
Answer: a set of subcortical structures that directs intentional movements
2. internal capsule
Answer: bundle of axons that transfers information to and from the cortex involved in
corticospinal tract
3. cerebral peduncle
Answer: midbrain area fibers that connect cortex to brainstem involved in corticospinal tract
4. medullary pyramids
Answer: triangular divisions within the medulla involved in corticospinal tract
5. red nucleus
Answer: a large nucleus of the midbrain that receives inputs from the motor cortex and
sends axons to motor neurons in the spinal cord involved in rubrospinal tract
6. vestibular nuclei
Answer: pons nuclei that receive information from the vestibular organs involved in
vestibulospinal tract
7. superior colliculus
Answer: midbrain, for visual reflexes and spatial orienting involved in tactospinal tract
8. pontine reticular formation
Answer: area of the pons with many nuclei involved in pontine reticulospinal tract
9. premotor area (PMA)
Answer: just in front of M1, lateral, for planning movements
10. supplementary motor area (SMA)
Answer: just in front of M1, medial, modulates the activity of the primary motor cortex
11. posterior parietal cortex (PPC)
Answer: combines input from sensory areas for higher-level functions
12. globus pallidus (GP)
Answer: subcortical structure part of basal ganglia, mediates movements, projects to VLo
13. ventral lateral nucleus (VLo)
Answer: in thalamus, controls motor information, projects to cortex
14. striatum (caudate nucleus + putamen)
Answer: subcortical structure part of basal ganglia, projects to GP
15. subthalamic nucleus (STN)
Answer: receives projection from cortex for the indirect pathway, part of basal ganglia
Page 1
, 16. substantia nigra (SN)
Answer: in midbrain, produces dopamine, can excite or inhibit striatum
17. somatic motor system
Answer: muscles + neurons that control muscles coordinates unconscious and conscious
movement
18. motor programs
Answer: circuits that evoke patterns of activity to coordinate movement
19. alpha motor neurons
Answer: directly trigger the generation of force by muscles
20. what drives alpha motor neurons
Answer: upper motor neurons in cortex and brainstem
21. hierarchy of motor processing (functions and brain areas of each level)
Answer: highest level: strategy/goal of movement (cortex, basal ganglia) middle level:
determining sequence of contractions (cortex, cerebellum) lowest level: execution to activate
motor and interneuron pools to generate movement (brainstem, spinal cord)
22. axons from brain to spinal cord descend along two categories of pathways (name
and location)
Answer: voluntary = lateral reflexive = ventromedial
23. list the two voluntary pathways
Answer: corticospinal and rubrospinal tracts
24. corticospinal tract path
Answer: cortex -> internal capsule -> cerebral peduncle -> medullary pyramid ->
decussates at medulla/spinal cord -> spinal cord
25. rubrospinal tract path
Answer: red nucleus in midbrain -> decussates immediately -> pons -> medulla -> spinal
cord receives inputs from similar motor areas as corticospinal tract
26. lesions to voluntary pathway
Answer: both lesions cause deficits in movement (slower, less precise, less accurate) but,
corticospinal tract lesions are less harmful as long as rubrospinal tract is in tact
27. list the four reflexive pathways and their functions
Answer: vestibulospinal (head turning) tectospinal (orienting to objects) pontine
reticulospinal (extensors in lower limbs/posture) medullary reticulospinal (inhibits excessive
reflex activity to maintain posture)
28. vestibulospinal tract pathway
Answer: vestibular system -> vestibular nucleus -> bilateral projection to spinal cord
29. tectospinal tract pathway
Answer: retina input -> superior colliculus -> decussates immediately -> spinal cord
30. pontine reticulospinal tract pathway
Answer: pontine reticular formation -> medullary reticular formation -> ipsilateral spinal
cord **no decussation
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