Upper Motor Neurons originate in the motor cortex or brainstem and carry motor signals from the brain to Lower Motor Neurons. Lower Motor Neurons exit the central nervous system and connect to neuromuscular junctions, acting as the final pathway for motor commands. Together, Upper and Lower Motor Neurons relay motor information from the brain to muscles.

2. Upper Motor Neurons are motor neurons that originate
either in the motor region of the cerebral cortex or in
the brain stem and carry motor information down to
the lower motor neurons
Lower Motor Neurons are motor neurons coming out
of CNS. They’re connected to neuromuscular junction
and they’re the final common pathways of motor
system. (AHCs or Brainstem nuclei)