(1910-1977), neurophysiologist William Grey Walter (also known as Grey Walter) was born in Kansas City, Missouri, on 19 February 1910 to journalist parents Karl Wilhelm Walter (1880-1965) and Minerva (Margaret) Lucrezia Hardy (1879-1953). The Walter family moved from the United States to Britain in 1915, where William remained for the rest of his life. He was educated at Westminster School (1922-1928), before taking the Natural Science Tripos at King’s College, Cambridge (1928-1931). He went on to pursue postgraduate research on nerve physiology and conditioned reflexes, gaining his MA in 1935. After completing his MA, Walter was invited to work at the Central Pathological Laboratory of the Maudsley Hospital, London, under neuropsychiatrist Frederick Lucien Golla (1877-1968). Since the late 1920s, Golla had become increasingly interested in the clinical applications of the burgeoning field of electroencephalography (EEG), the measurement of the electrical activity of the brain via electrodes placed on the scalp. Noting his skill in technical matters, Golla encouraged Walter to develop increasingly sophisticated EEG devices, and supported his application for a Rockefeller Travelling Fellowship to visit the Jena laboratory of German physiologist Hans Berger (1873-1941), widely credited as the founder of electroencephalography. Walter went on to achieve several key ‘firsts’ in electroencephalography, including the first detection of a cerebral tumour using the technique in 1936. Between 1936 and 1939, Walter expanded his research programme and took readings from hundreds of patients, focusing particularly on the electrical patterns of epilepsy. In 1939, Golla was invited to become director of the new Burden Neurological Institute, Bristol, an independent research unit specialising in the investigation and treatment of neurological, psychological, and psychiatric disorders, and invited Walter to become director of the Institute’s Physiology Department. At the Burden, Walter further developed his EEG apparatus, developing the automatic frequency analyser and the toposcope in 1943 and 1950 respectively. His research programme also became increasingly ambitious, with investigations into the cerebral effects of stroboscopic light beginning in 1947 and, later, the discovery of ‘contingent negative variation’ (CNV, or the ‘expectancy wave’) in the 1960s. Walter also played a key role in the professionalization of electroencephalography during this period, co-founding the journal Electroencephalography and Clinical Neurophysiology and organising meetings of the EEG Society (1943-1989). Outside of his clinical work, Walter became a key figure in early British cybernetics, the study of feedback, control, and communication systems in humans and machines that synthesised approaches from engineering, biology, and mathematics. He co-founded the Ratio Club, an informal dining and discussion group which provided a key social outlet for cybernetic enthusiasts, which met between 1949 and 1955. He also built several cybernetic devices in his spare time, the most famous of which were his robotic tortoises, or Machina Speculatrix, designed to function as simple models of the adaptable human brain. These received national attention when they were exhibited on television in 1950 and at the Festival of Britain in 1951. He also became a prolific public intellectual, writing 170 scientific publications, serving as an expert witness in court courses, appearing frequently on the BBC, and writing an immensely popular non-specialist text on his neuroscientific work, The Living Brain (1953). His work also gained a surprising popularity among counter-cultural artists during the 1950s and 1960s, including Beat writers William S. Burroughs and Allen Ginsberg, who saw Walter’s research as part of a broader investigation of human consciousness. Walter was married twice, first to Katharine Monica Ratcliffe in 1934 and then to Vivian Joan Dovey (1915-1980) in 1947, with whom he had one son, Timothy Walter (1949-1976). Walter and Dovey separated in 1960 and divorced in 1973. After their separation, Walter lived with Lorraine Josephine Aldridge (née Donn) until 1972. In 1970, Walter suffered severe brain damage following a road accident, forcing him to retire from full-time research work. He died of a heart attack in 1977.

(1904-1995), neurophysiologist Mary (Mollie) Agnes Burnston Brown Brazier was born in Weston-Super-Mare, Somerset on 18 May 1904. She was educated at Sidcot School, Somerset and Bedford College, Bedford, before studying physiology and biochemistry at the University of London, gaining her BSc in 1926 and Ph.D. in 1930. Her first major research project, conducted at the Maudsley Hospital, London, focused on electrical changes in the skin that occur in thyroid disease. This work received great acclaim, and was awarded the Gold Medal of the Institute of Electrical Engineers and the Van Meter Prize of the American Association for the Study of Goitre in 1934. Following this project, Brazier became increasingly interested in the electrical activity of the human nervous system. After receiving a Rockefeller Fellowship in 1940, Brazier moved from London to the Massachusetts General Hospital (MGH) in Boston, Massachusetts, where she took up a number of posts as a neurophysiologist in the Departments of Psychiatry, Anaesthesia, and Neurology. While her research in Boston covered a variety of subjects – including psychological selection processes, neurological injuries, and electromyography – Brazier increasingly specialised in electroencephalography (EEG, the measurement of the electrical activity of the brain), running the Hospital’s EEG Laboratory for much of the Second World War. In 1946, Brazier played a key role in persuading William Grey Walter (1910-1977), a neurophysiologist and EEG expert at the Burden Neurological Institute in Bristol, England, to come to Boston and demonstrate his new EEG frequency analyser device. The device remained in Boston, and helped to facilitate Brazier’s path-breaking computerised analyses of brainwave patterns. In 1961, Brazier left Massachusetts to join the Brain Research Institute at the University of California, Los Angeles (UCLA), where she was appointed Professor of Anatomy, Physiology and Biophysics. Here, she expanded her research on the electrical activity in the brain and nervous system, specialising in the use of computing methods to evaluate patients with epilepsy for surgical treatment. During her career, Brazier played a key role in expanding the international reach of several neuroscientific disciplines. She wrote a seminal textbook The Electrical Activity of the Nervous System in 1957, and was successively appointed Treasurer, Secretary, and finally President of the International Federation of Societies for Electroencephalography and Clinical Neurophysiology. She also wrote a number of texts on the history of neurophysiology, including A History of Neurophysiology in the 17th and 18th Centuries (1984) and A History of Neurophysiology in the 19th Century (1988). She continued writing in academic circles right up to her death, with her last essay published in the Journal for the History of the Neurosciences in 1993. Brazier married Leslie J. Brazier, an electrical engineer, in 1928, with whom she had one son. She died in Falmouth, Massachusetts, on 14 May 1995.

The Edison and Swan Electric Light Company Limited was a manufacturer of electrical goods based in London, England. It was founded by chemist and inventor Sir Joseph Wilson Swan (1828-1914) on 26 October 1883. In 1860, Swan began conducting experiments in electric lighting. After several setbacks, Swan successfully produced an incandescent electric lamp in 1878, which he patented on 27 November 1880 (Patent No. 4933). After setting up the Swan United Electric Company to commercially produce the lamp, Swan was threatened with legal action by the rival Edison Electric Light Company, who claimed infringement of the patents taken out by American inventor and scientist Thomas Edison (1847-1931). Instead of going to trial, the two companies agreed to merge, becoming the Edison and Swan United Electric Light Company Limited in 1883. By combining forces, the Company was able to suppress competition in Britain and dominate the market with their ‘Ediswan’ light bulbs, produced in factories in Sunderland, Brimsdown, and Ponders End. In the early twentieth-century, the company expanded beyond light bulbs, opening the country’s first radio valve factory in 1916 and beginning the production of vacuum cleaners in 1924. In following years, Edison and Swan factories also produced radio sets, car batteries, cathode ray tubes, and electric cables. During the Second World War, the company assisted researchers at the Burden Neurological Institute, Bristol, in their production of equipment for electro-convulsive therapy (ECT) and electroencephalography (EEG). In 1957, the Edison and Swan Electric Company was amalgamated with Siemens Brothers and Company within the Associated Electrical Industries Group (AEI) to form Siemens Edison Swan Limited. Siemens Edison Swan light bulbs were also produced under the Mazda (General Electric) brand licence.