Topic 19: Nervous System - Nervous System Pathways - Descending Flashcards
1
Q
What does the descending pathway (motor) do?
A
- conduct impulses away from brain to effector
2
Q
are the two neuron descending pathways?
A
upper motor neuron (CNs)
lower motor neuron (PNS)
3
Q
what is the upper motor neuron? (2)
A
- multiple interneurons
- cell bodies in cortex or brainstem nuclei
4
Q
What is the lower motor neuron?
A
- axons of upper motor neuron form descending spinal tracts
5
Q
what are the two descending tracts?
A
- corticospinal tract
- indirect tract
6
Q
What are corticospinal tracts?
A
- cell bodies in cerebral cortex
7
Q
What is the function of the corticospinal tract?
A
- decussate in medulla
8
Q
Where are cell bodies in indirect tract?
A
- brainstem nuclei
9
Q
what is the function of the indirect tract?
A
- receive impulses from motor cortex, basal nuclei, cerebellum
