SPLH 620 - Exam 3 Questions Answered Correctly Latest Update 2025-2026
What structures are part of the pyramidal system? - Answers Brainstem & spinal cord
What are the cortical areas for direct motor control? - Answers Primary motor cortex (M1)
Premotor cortex (PMC)
Supplementary motor cortex (SMA)
What is the function of the internal capsule? - Answers Consists of descending axons for the
spinal motor pathway and ascending axons for the somatosensory pathways
Describe the UMN process in the Spinal Motor Pathway - Answers - cerebral cortex to spinal
cord
- descend through internal capsule
- decussates in medulla
- synapse in anterior horn of the spinal cord (corticospinal tract)
Describe the LMN process in the Spinal Motor Pathway - Answers - cell body in anterior horn of
spinal cord (corticospinal tract)
- synapse with muscle fibers (aka a motor unit)
Describe the UMN process in the Bulbar Motor Pathway - Answers - cerebral cortex to
brainstem
- descend through internal capsule
- synapse on cranial nerve nuclei (corticobulbar tract)
Describe the LMN process in the Bulbar Motor Pathway - Answers - cell body in cranial nerve
nuclei
- synapse with muscle fibers (aka a motor unit)
Is the Spinal Motor Pathway contralateral or bilateral? - Answers Contralateral
Is the Bulbar Motor Pathway contralateral or bilateral? - Answers Mostly bilateral, with a couple
pathways being contralateral
True or false: the bulbar and spinal motor pathways involve the thalamus - Answers FALSE
What is the function of the corticobulbar tract? - Answers It connects the cerebral cortex to the
brainstem with the purpose of innervating the craniofacial muscles
, How does the brainstem function as a conduit (a. passage for signal conduction)? - Answers -
carries the corticospinal tract for motor movement
- carries the DC/ML pathway for touch and proprioception
- carries the spinothalamic tract/ALS pathway for pain and temperature
How does the brainstem affect cranial nerve function? - Answers It supplies cranial nerve
function for the head and craniofacial structures
In what ways does the brainstem integrate information? - Answers The use of reticular
formation and central pattern generators
reticular formation - Answers a loosely connected neural network of interneurons in the
brainstem that controls complex, rhythmic behavior patterns, complex motor patterns, aspects
of respiratory and cardiovascular activity, and consciousness
central pattern generators - Answers neural mechanisms in the spinal cord that generate
rhythmic patterns of motor output such as locomotion, respiration, and swallowing
What are the 32 segments of the spinal cord? - Answers 8 cervical
12 thoracic
5 lumbar
5 sacral
1 coccygeal
Dorsal rootlets: sensory or motor? - Answers sensory
Ventral rootlets: sensory or motor? - Answers motor
What is formed by the merge of the dorsal and ventral rootlets? - Answers the spinal nerve
Where are the cell bodies of lower motor neurons located? - Answers anterior horn in the spinal
cord
Funiculi: what kind of matter? - Answers white matter
Horns: what kind of matter? - Answers gray matter
What is a motor unit? - Answers A lower motor neuron and all of the muscle fibers it innervates
Difference between small and large motor units? - Answers Small: 1:10 ratio, used for low force,
fine motor control
Large: 1:1000 ratio, used for high force, gross motor control
What structures are part of the pyramidal system? - Answers Brainstem & spinal cord
What are the cortical areas for direct motor control? - Answers Primary motor cortex (M1)
Premotor cortex (PMC)
Supplementary motor cortex (SMA)
What is the function of the internal capsule? - Answers Consists of descending axons for the
spinal motor pathway and ascending axons for the somatosensory pathways
Describe the UMN process in the Spinal Motor Pathway - Answers - cerebral cortex to spinal
cord
- descend through internal capsule
- decussates in medulla
- synapse in anterior horn of the spinal cord (corticospinal tract)
Describe the LMN process in the Spinal Motor Pathway - Answers - cell body in anterior horn of
spinal cord (corticospinal tract)
- synapse with muscle fibers (aka a motor unit)
Describe the UMN process in the Bulbar Motor Pathway - Answers - cerebral cortex to
brainstem
- descend through internal capsule
- synapse on cranial nerve nuclei (corticobulbar tract)
Describe the LMN process in the Bulbar Motor Pathway - Answers - cell body in cranial nerve
nuclei
- synapse with muscle fibers (aka a motor unit)
Is the Spinal Motor Pathway contralateral or bilateral? - Answers Contralateral
Is the Bulbar Motor Pathway contralateral or bilateral? - Answers Mostly bilateral, with a couple
pathways being contralateral
True or false: the bulbar and spinal motor pathways involve the thalamus - Answers FALSE
What is the function of the corticobulbar tract? - Answers It connects the cerebral cortex to the
brainstem with the purpose of innervating the craniofacial muscles
, How does the brainstem function as a conduit (a. passage for signal conduction)? - Answers -
carries the corticospinal tract for motor movement
- carries the DC/ML pathway for touch and proprioception
- carries the spinothalamic tract/ALS pathway for pain and temperature
How does the brainstem affect cranial nerve function? - Answers It supplies cranial nerve
function for the head and craniofacial structures
In what ways does the brainstem integrate information? - Answers The use of reticular
formation and central pattern generators
reticular formation - Answers a loosely connected neural network of interneurons in the
brainstem that controls complex, rhythmic behavior patterns, complex motor patterns, aspects
of respiratory and cardiovascular activity, and consciousness
central pattern generators - Answers neural mechanisms in the spinal cord that generate
rhythmic patterns of motor output such as locomotion, respiration, and swallowing
What are the 32 segments of the spinal cord? - Answers 8 cervical
12 thoracic
5 lumbar
5 sacral
1 coccygeal
Dorsal rootlets: sensory or motor? - Answers sensory
Ventral rootlets: sensory or motor? - Answers motor
What is formed by the merge of the dorsal and ventral rootlets? - Answers the spinal nerve
Where are the cell bodies of lower motor neurons located? - Answers anterior horn in the spinal
cord
Funiculi: what kind of matter? - Answers white matter
Horns: what kind of matter? - Answers gray matter
What is a motor unit? - Answers A lower motor neuron and all of the muscle fibers it innervates
Difference between small and large motor units? - Answers Small: 1:10 ratio, used for low force,
fine motor control
Large: 1:1000 ratio, used for high force, gross motor control
