MUNE is a non-invasive, electrophysiologic method to estimate the number of motor neurons innervating a muscle or group of muscles. The ability to quantitatively estimate the number of surviving motor neurons is useful in the following areas: (a) clinically for diagnosis of neuromuscular disorders; (b) as an endpoint measure in clinical drug trials for lower motor neuron disorders; and (c) as a tool to obtain insight into the natural history and pathophysiology of lower motor neuron disorders. Relevant lower motor neuron disorders include amyotrophic lateral sclerosis (ALS), spinal muscular...