The French neurologist who discovered Parkinson's disease was also the person who discovered ALS (amyotrophic lateral sclerosis), also known as Lou Gehrig's disease, or motor-neuron disease. It is a progressive, degenerative neurological disorder in which some of the brain's nerve cells gradually deteriorate. The affected nerve cells are the ones that control swallowing and breathing, as well as movement in your limbs. So as the disease progresses, you lose the ability to move, speak, eat and, eventually, breathe. Sadly, the affliction is 100 percent fatal — you generally die a mere two to five years after being diagnosed. There is little to no pain with the disease, however, and your senses and thinking are left intact. In the U.S., about 5,000 people annually are given this diagnosis. The well-known ALS ice bucket challenge raises millions for research [sources: ALS Association, Web MD].
The disease was first discovered in 1869 by Jean-Martin Charcot. But it was little known until it hit baseball star Lou Gehrig in 1939. Gehrig was just 35 years old at the time and at the peak of his career. After the news leaked, he gave a farewell speech to fans on July 4, 1939 in which he called himself "the luckiest man on the face of the earth" for having a wonderful family, and having been able to play pro ball. Two years later, he was gone. After his death, the disease quickly became known as Lou Gehrig's disease — at least among Americans — and knowledge of the illness soared. Today, perhaps because Gehrig is long gone, Lou Gehrig's disease is more commonly known as ALS [sources: Lou Gehrig, National Baseball Hall of Fame].