Describe the locations and functions of the upper and lower motor neurons in a motorpathway.

Upper Motor Neurons (UMNs) are located in the motor region of the cerebral cortex. They are also found in the brainstem. The cell bodies of UMNs are located in the cerebral cortex, and their axons form the descending tracts that communicate with the lower motor neurons. The function of UMNs is to carry the motor information down to the lower motor neurons. They are responsible for initiating voluntary movements and for carrying the nerve impulses that control the hard-wired, involuntary movements maintained at the brainstem level.

Lower Motor Neurons (LMNs) are located in the spinal cord and the brainstem. The cell bodies of LMNs are located in the anterior grey column and the cranial nerve nuclei of the brainstem. Their axons leave the CNS (Central Nervous System) and extend through peripheral nerves to supply the skeletal muscles. The function of LMNs is to connect the brainstem and spinal cord with muscle fibers, bringing the nerve impulses from the upper motor neurons out to the muscles. They are responsible for muscle contraction which allows for movement to occur.