NOTE: The pyramidal system is composed of very long neurons whose cell bodies are in layer V of the cortex and whose first synapse is in the motor neuron pool in the spinal cord. The Corticobulbar system is similar except the neurons synapse with nuclei of facial nerves in the brain stem. Approximately 80 to 90% cross in the brainstem and the remaining descend as in the ventral corticospinal tract. Almost all synapse on connecting or interneurons in the spinal cord.

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