Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disorder that primarily affects motor neurons.The characteristic features of this devastating disorder are the simultaneous presence of upper and lower motor neuron(LMN) signs with progression from one region of the neuraxis to the next and eventual death, typically from respiratorycompromise.Electrophysiological studies are an indispensible part of the ALS evaluation, especially serving as an extension of theclinical examination, and most useful in identifying LMN dysfunction. Not only may electrodiagnostic studies revealcharacteristic changes in those regions clinically manifesting signs, but it also serves to disclose asymptomatic areas ofinvolvement.
