ABSTRACT
The populations of neurons responsible for carrying the impulse that leads to the execution of a voluntary movement are the upper and lower motor neurons. The cell bodies of the upper motor neurons are located in the motor cortex from where their axons project downward to connect with the lower motor neurons within the motor nuclei of the brainstem and the anterior horn of the spinal cord. While the upper motor neurons are contained entirely within the CNS, the axons of the lower motor neurons exit to make connections with the striated muscles.
