premise: Amyotrophic lateral sclerosis is an affliction.
hypothesis: Amyotrophic lateral sclerosis ( ALS ) , also known as Lou Gehrig 's disease and motor neurone disease ( MND ) , is a specific disease that causes the death of neurons which control voluntary muscles . The average survival from onset to death is two to four years . Most die from respiratory failure . A motor neuron disease ( MND ) is any of several neurological disorders that selectively affect motor neurons , the cells that control voluntary muscles of the body .