Hawking suffers from a rare early-onset slow-progressing form of amyotrophic lateral sclerosis (ALS), also known as motor neurone disease or Lou Gehrig's disease, that has gradually paralysed him over the decades.[20]
Hawking had experienced increasing clumsiness during his final year at Oxford, including a fall on some stairs and difficulties when rowing.[34][35] The problems worsened, and his speech became slightly slurred; his family noticed the changes when he returned home for Christmas and medical investigations were begun.[36][37] The diagnosis of motor neurone disease came when Hawking was 21, in 1963. At the time, doctors gave him a life expectancy of two years.[38][39]
In the late 1960s, Hawking's physical abilities declined: he began to use crutches and ceased lecturing regularly.[40] As he slowly lost the ability to write, he developed compensatory visual methods, including seeing equations in terms of geometry.[41][42] The physicist Werner Israel later compared the achievements to Mozart composing an entire symphony in his head.[43][44] Hawking was, however, fiercely independent and unwilling to accept help or make concessions for his disabilities. He preferred to be regarded as "a scientist first, popular science writer second, and, in all the ways that matter, a normal human being with the same desires, drives, dreams, and ambitions as the next person."[45] His wife Jane Hawking later noted that "Some people would call it determination, some obstinacy. I've called it both at one time or another."[46] He required much persuasion to accept the use of a wheelchair at the end of the 1960s,[47] but ultimately became notorious for the wildness of his wheelchair driving.[48] Hawking was a popular and witty colleague, but his illness, as well as his reputation for brashness and intelligence, distanced him from some.[46]
Hawking's speech deteriorated, and by the late 1970s he could only be understood by his family and closest friends. To communicate with others, someone who knew him well would translate his speech into intelligible speech.[49] Spurred by a dispute with the university over who would pay for the ramp needed for him to enter his workplace, Hawking and his wife campaigned for improved access and support for those with disabilities in Cambridge,[50][51] including adapted student housing at the university.[52] In general, however, Hawking had ambivalent feelings about his role as a disability rights champion: while wanting to help others, he sought to detach himself from his illness and its challenges.[53] His lack of engagement led to some criticism.[54]
During a visit to the European Organisation for Nuclear Research on the border of France and Switzerland in mid-1985, Hawking contracted pneumonia, which in his condition was life-threatening; he was so ill that Jane was asked if life support should be terminated. She refused but the consequence was a tracheotomy, which would require round-the-clock nursing care, and remove what remained of his speech.[55][56] The National Health Service would pay for a nursing home, but Jane was determined that he would live at home. The cost of the care was funded by an American foundation.[57][58] Nurses were hired for the three shifts required to provide the round-the-clock support he required. One of those employed was Elaine Mason, who was to become Hawking's second wife.[59]
For his communication, Hawking initially raised his eyebrows to choose letters on a spelling card.[60] But he then received a computer program called the "Equalizer" from Walt Woltosz. In a method he uses to this day, using a switch he selects phrases, words or letters from a bank of about 2,500–3,000 that are scanned.[61][62] The program was originally run on a desktop computer. However, Elaine Mason's husband, David, a computer engineer, adapted a small computer and attached it to his wheelchair.[63] Released from the need to use somebody to interpret his speech, Hawking commented that "I can communicate better now than before I lost my voice."[64] The voice he uses has an American accent and is no longer produced.[65][66] Despite the availability of other voices, Hawking has retained this original voice, saying that he prefers it and identifies with it.[67] At this point, Hawking activated a switch using his hand and could produce up to 15 words a minute.[68] Lectures were prepared in advance and were sent to the speech synthesiser in short sections to be delivered.[65]
Hawking gradually lost the use of his hand, and in 2005 he began to control his communication device with movements of his cheek muscles,[69][70][71] with a rate of about one word per minute.[70] With this decline there is a risk of him developing locked-in syndrome, so Hawking is collaborating with researchers on systems that could translate Hawking's brain patterns or facial expressions into switch activations.[71][72][73] By 2009 he could no longer drive his wheelchair independently.[74] He has increased breathing difficulties, requiring a ventilator at times and has been hospitalised several times.[72]
Marriages