Amyotrophic lateral sclerosis (ALS, sometimes called Lou Gehrig's Disease, Maladie de Charcot or motor neuron disease) is a progressive, fatal, neurodegenerative disease caused by the degeneration of motor neurons, the nerve cells in the central nervous system that control voluntary muscle movement. The disorder causes muscle weakness and atrophy throughout the body as both the upper and lower motor neurons degenerate and die, ceasing to send messages to muscles. Unable to function, the muscles gradually weaken, atrophy (shrink and lose function), and develop fasciculations (twitches) because of denervation (loss of nerve stimulation). Eventually, the brain completely loses its ability to initiate and control voluntary movement. The disease does not necessarily debilitate the patient's mental functioning in the same manner as Alzheimer's disease or other neurological conditions. Rather, those suffering advanced stages of the disease may retain the same memories, personality, and intelligence they had before its onset....

Amyotrophic lateral sclerosis (ALS, sometimes called Lou Gehrig's Disease, Maladie de Charcot or motor neuron disease) is a progressive, fatal, neurodegenerative disease caused by the degeneration of motor neurons, the nerve cells in the central nervous system that control voluntary muscle movement. The disorder causes muscle weakness and atrophy throughout the body as both the upper and lower motor neurons degenerate and die, ceasing to send messages to muscles. Unable to function, the muscles gradually weaken, atrophy (shrink and lose function), and develop fasciculations (twitches) because of denervation (loss of nerve stimulation). Eventually, the brain completely loses its ability to initiate and control voluntary movement. The disease does not necessarily debilitate the patient's mental functioning in the same manner as Alzheimer's disease or other neurological conditions. Rather, those suffering advanced stages of the disease may retain the same memories, personality, and intelligence they had before its onset.

ALS is one of the most common neuromuscular diseases worldwide, and people of all races and ethnic backgrounds are affected. 1 to 2 people per 100,000 develop ALS each year. ALS most commonly strikes people between 40 and 60 years of age, but younger and older people can also develop the disease. Men are affected slightly more often than women.