Stephen Hawking, who celebrated his 67th birthday on January 8, has led a long and celebrated life as a physics scholar and academic celebrity. He is the author of the wildly successful books A Brief History of Time and The Universe in a Nutshell, as well as countless other publications.

Science buffs may be aware of some of the areas which his work has spanned, including the study of black holes, relativity, and cosmology. He is gifted with a knack for simplifying complicated concepts so that the general masses can enjoy and understand his work.

Stephen Hawking was diagnosed with amyotrophic lateral sclerosis (ALS, otherwise known as Lou Gehrig’s disease) at the tender age of 21, and was told his life expectancy was only 2 or 3 years. Initially crushed at the news, he soon married and later had a family. His illness has slowly robbed him of the ability to move and speak, and confined him to a wheelchair, but he continues to work today. In April of 2007, he became the first quadriplegic to float in zero-gravity.

ALS is a progressive (usually fatal) neuromuscular disease, in which motor neurons degenerate over time. Muscles progressively weaken and atrophy (shrink) from disuse and patients may lose all ability to move any muscles, including the muscles that control breathing. Sensory nerves, which control the ability to feel and to sense pain and pressure, are usually not affected. Mental capacity is likewise not usually affected, and most certainly has not been affected in Hawking’s case.

Stephen Hawking is an inspiration for the millions of Americans who suffer severe disabilities. His career has spanned 40+ years, much of which has been spent in a wheelchair. Although his body has weakened, his mind remains as strong as ever.

Related Links:

• What is ALS? from the ALS Association
• Amyotrophic Lateral Sclerosis Fact Sheet from the National Institute of Neurological Disorders and Stroke
• ALS - Lou Gehrig's Disease from the Neurology Channel