Distinction between Lower & Upper motor neurons

LMN

origin: Brainstem & spinal cord

Destination: Muscles

Function: produce muscle actions for reflexex, & carry out UMN commands for voluntary movt

Sings of Lessions: Dimished

reflexex,

decreases muscle tone ,

Atrophy

UMN

origin: cerebral cortex

Destination: cranial and spinal nerve nuclei

Function: Control voluntary movement

Sings of Lessions: weakness and loss of skilled movement