Professor Patrick Wall

Patrick David Wall, physiologist and neuroscientist: born Nottingham 25 April 1925; Instructor, Yale School of Medicine 1948-50; Assistant Professor, University of Chicago 1950-53; Instructor, Harvard University 1953-55; Associate Professor, Massachussetts Institute of Technology 1957-60, Professor 1960-67; Professor of Anatomy and Director, Cerebral Functions Research Group, University College London 1967-90 (Emeritus, based in Physiology Department, St Thomas' Hospital); FRS 1989; three times married; died London 8 August 2001.

Patrick Wall was the world's leading expert on pain: his work led to the development of pain-relief devices that are used by thousands of people around the world, and to the development of epidural anaesthetics. The pain-relief devices, known as Tens (trans-cutaneous electrical nerve stimulation), were developed with the American neurosurgeon William Sweet. Their rationale is based on the gate theory of pain, developed by Wall in collaboration with the Canadian psychologist Ron Melzack.

His other inventions included underpant elastic that gripped clothes, and hearing aids embedded in spectacle arms.

Melzack and Wall, who described themselves as "two iconoclasts", were intellectual collaborators, chewing over ideas in their spare time: so far as I know they never experimented together. At Melzack's suggestion they wrote a paper on pain, published in the journal Brain in 1962; this was when the gate theory was born. According to Wall, about three people read it. So they wrote another paper, initially saying essentially the same things, but as the two papers went back and forth between them in the drafting stage, their ideas were developed. "Pain Mechanisms: a new theory" was published in Science in 1965. According to Melzack, some people loved it but most hated it.

The gate theory threw away the Cartesian model of pain travelling up a string of nerves from the extremities to the brain. It explained why people feel pain although there are no such thing as pain-nerve fibres, only fibres transmitting pressure and touch. It proposed a gating mechanism within the spinal cord that controls the flow of signals to the brain in a way that determines whether the signal is perceived as painful. The theory suggests that the body can inhibit these pain signals or "close the gate" by activating certain nerve fibres in the spinal cord. This explains why soldiers rarely feel injuries inflicted on the battlefield, and why amputees can feel phantom pain in their missing limbs. It also explains, for example, why a newborn rat shows a much greater response to pain when alone than when with its mother.

The theory moved the ideas about pain away from the brain and the body's peripheries to the spinal cord. It only started to be taken seriously after the Tens devices, based on the theory, were manufactured and found to be widely effective. It also opened up research into the neurochemistry of pain, and research into the chemical called Substance P in the spinal cord.

Wall was particularly angered by cancer pain, long before his own cancer, because it comes on too late to prompt the patient to seek medical help, and serves no useful purpose.

His other great contribution to science was mapping the layers of the dorsal horn, which is the column of sensory transmission neurones at the back of the spinal cord, and he was the author of several hundred scientific papers.

Wall was the founding editor of the medical journal Pain, and the erudite and accessible author of several books on the subject. The most recent, Pain: the science of suffering (1999), was written when he had advanced cancer. It was a tour de force and was widely reviewed and lavishly praised. "You won't meet a finer piece of popularisation this year than Patrick Wall's crack at one of medicine's greatest mysteries," said Roy Porter in The Times. "A first-class, well-written account of what is known about pain and how to relieve it, by one of the world's greatest experts on the subject," said Anthony Storr in The Sunday Times.

His other books included a successful thriller, Trio – the Revolting Intellectuals Organisation (1965), as well as Defeating Pain (1991) and The Challenge of Pain (with Ron Melzack, 1982). He was co-editor, with Ron Melzack, of the Textbook of Pain, first published in 1983 with three further editions since.

Pat Wall was born in Nottingham in 1925 and educated at St Paul's School in London, where, he said, most of the boys seemed set to be high-fliers, apart from the one who took an apprenticeship in the catering trade; his name was Clement Freud. After qualifying in medicine at Christ Church, Oxford, he went to the United States, where he had a series of distinguished appointments at Yale, Chicago, Harvard and the Massachusetts Institute of Technology. He returned to the UK in 1967 as Professor of Anatomy at University College London. He was also the director of the Cerebral Functions Unit, which attracted the best neuroscience researchers. In 1972, after a trip to Israel, he also had a chair at the Hebrew University of Jerusalem, spending several months there each year.

When he formally retired at the age of 67 he was appointed to a visiting chair at King's, Guy's and St Thomas's School of Medicine. He set up his laboratory in a room on the first floor of St Thomas's medical school building, working away in his usual fashion until 5pm, socialising over a beer for an hour or so, and writing books and learned papers in the evenings.

The Royal Society, who have always been slow to recognise medical scientists, elected him a Fellow in 1989, by which time he had, according to reliable sources, been short-listed several times for a Nobel Prize. He received many other awards for his life's work, including from the British Neuroscience Association, which he helped found, the Royal College of Anaesthetists, and universities in Italy and Hungary. The 1999 World Congress on Pain in Vienna was dedicated to him.

He was a champion of underdogs and committedly left-wing; the only enemies he engendered were those who disapproved of his politics. He did many acts of kindness in his life. As he kept quiet about these, all I can recount are those I saw, which included getting a paralysed friend of mine a place at Stoke Mandeville Hospital, and helping re-locate the squatters who were evicted from the Arts Council building in Piccadilly in 1970. He took pleasure in all forms of creativity and wit, helping many young British artists. He stood up for causes he believed in, such as the necessity of using animals in medical research. He detested the tosh talked by alternative health practitioners.

He lived frugally and had few possessions, but gave quietly and generously to the many causes he believed in. He was self-deprecating but often blew the trumpet for other people. Despite his friendliness, wit and charm, he was an intensely private person.

Having ignored various health problems for a long while, he collapsed on holiday in Cork in 1996 and was found to have a widely disseminated prostate cancer and extensive kidney damage. Treatment gave him five years' remission. On 2 August this year he underwent a kidney procedure. On 8 August he discharged himself home, saying that he recognised from his clinical experience what people were like when they were close to death. He died that evening.

Six weeks earlier he had travelled to Boston to give the first of a series of annual Harry Beecher lectures, named in honour of Harvard's first professor of anaesthetics. Towards the end of his life he said that the most useful thing he had ever done was to serve on the Gardiner Committee in the 1970s, examining the effects of rubber bullets in Northern Ireland.

He divorced his first wife, Betty, an artist and poet, in 1973 after 25 years of marriage; she died in 1998. His second marriage, to Vera, also an artist, was short-lived. In 1999 he married Mary Helton, who promoted young British women rap musicians. He had no children. He left his body for medical education; it will be dissected at Charing Cross, rather than his old department at University College.

Caroline Richmond