Disability: Motor Neuron disease or a variant of ALS (Amyotrophic Lateral Sclerosis)
Stephen Hawking is severely disabled by motor neuron disease, likely a variant of the disease known as amyotrophic lateral sclerosis (or ALS). Symptoms of the disorder first appeared while he was enrolled at Cambridge; he lost his balance and fell down a flight of stairs, hitting his head. Worried that he would lose his genius, he took the Mensa test to verify that his intellectual abilities were intact. The diagnosis of motor neuron disease came when Hawking was 21, shortly before his first marriage, and doctors said he would not survive more than two or three years. Hawking gradually lost the use of his arms, legs, and voice, and as of 2009 was almost completely paralyzed.
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