by Adam Sillito, emeritus professor of physiology at the Institute of Ophthalmology in London, who has died aged 79, described one of his hobbies in Who’s Who as “dreaming of better things”. A lateral thinker who understood the bigger picture, he researched the mechanics of visual perception which provided vital information for future treatments. As director of the institute from 1991 to 2006, he transformed it from a dying backwater into a world-class center of excellence, working in partnership with Moorfields eye hospital and attracting top scientists from all over of the world.
In the 1970s, Sillito was a lecturer at the University of Birmingham and explored an aspect of the complex process of visual perception. In order to “see”, neurons must transmit information from the eyes to the visual cortex in the brain, where it is represented as images. At the time researchers were most interested in how neurotransmitters have an “exciting” effect on neurons, causing them to fire and transmit information to the next cell.
But Sillito was curious to find out if the opposite happens: do neurotransmitters stop neurons from firing? He carried out a series of experiments in the 70s which proved that this is the case: some neurotransmitters have an inhibitory effect.
It was a fundamental discovery. His colleague Javier Cudeiro said: “Adam showed that the inhibitory component was a key part of vision as we know it. It was a paradigm shift in the concept of how the visual system works, which proved fundamental to the modern understanding of visual neuroscience.”
In 1982, de Sillito became professor of physiology and head of department at Cardiff University. There and later in London, he explored a key brain area involved in vision, the lateral geniculate nucleus, showing that it played a role in inhibition and that it is involved in a variety of functions, including helping us understand is there such a thing as image focus or is. in the background.
He researched how vision affects what the brain expects to see. Some vision occurs through “bottom-up processing”, meaning that information comes in from the eyes and the brain has no expectations about what it sees. In “top-down processing”, however, expectations are set for what it might see.
An example of this is waiting for passers-by with hair or clothes similar to that of a friend you are waiting for. This type of visual processing involves many parts of the brain and Sillito’s research made key observations that opened up new avenues of research.
In a 2003 Guardian article, Our Lying Eyes , Sillito explained how Bridget Riley’s art – with its disturbing optical effects – offers a window into how visual perception works and how what we “see” can be framed by expectations of the brain.
In 1987 he was appointed professor of physiology at the Institute of Ophthalmology, with the task of trying to change it, as it was likely to be closed. The Research Assessment Exercise (now the Research Excellence Framework), which assesses research in UK higher education institutions, gave it the lowest possible score for having no significant academic output.
A logical, strategic thinker, Sillito knew that if he could recruit good scientists and raise the institution’s academic profile, funding would follow, which would change his fortunes. He encouraged researchers to “blue skies”, released them from teaching or management duties, and provided attractive conditions, such as good salaries and well-resourced laboratories.
He oversaw the institution’s merger with University College London in 1995 and its move to larger premises in Bath Street, near Moorfields eye hospital, with which it had a close partnership. Funding came in from the Wellcome Trust and Sillito urged the Fight for Sight charity, which has so far supported medical projects, to also support clean research.
It wasn’t all straightforward: the university’s decision-makers and Moorfields didn’t always agree, but Sillito was adamant. The institute’s score from the Research Assessment Exercise rose steadily and by 2008 it was rated “internationally excellent”.
Not long before she retired in 2018, her colleague Susan Lightman attended a meeting where the institute’s staff spoke about their careers. Like most of her British colleagues, she said she spent time in the United States, leading visual research at the time. The last speaker, however, was a new senior fellow at the Institute, who said: “Well, I didn’t have to go abroad to succeed.” Sillito’s work at the institute was testament to the fact that young academics were now able to carry out excellent research in the UK.
Sillito was born in Tamworth, Staffordshire, the son of Adam Sillito, a dairy farmer, and his wife, Jean (née Onion), who was a secretary at the Milk Marketing Board and kept the family farm accounts. The couple also had two daughters, Margaret and Susan.
From an early age Adam was interested in cars and anything mechanical, as well as biology, keeping various pets, including a rescue magpie and a jackdaw. At the age of six, he contracted polio and had to spend two years in hospital, seeing his family from the other side of a single glass screen. The disease left its mark on his right arm and meant that he did not start school until he was eight years old. A voracious reader, he rose quickly, passing the 11 plus exam to attend Burton-on-Trent grammar school. He first studied medicine at Birmingham University but switched to neurophysiology.
After his PhD, Sillito studied in Baltimore at Johns Hopkins University in 1970-71. He met physiotherapist Sharon Pascoe in Birmingham, when she signed up for a class he taught. She came out to be with him in the United States and had what she called a “hippie wedding” in 1971 and they went on a road trip to the west coast and back to celebrate. Returning to the United Kingdom, they made their home in Birmingham, where Sillito lectured and researched at the university.
In 2014 he retired from UCL, aged 70. He was diagnosed with bladder cancer in 2016, but nevertheless continued to enjoy a rich cultural life in London, including poetry, chess, music, and visits to Seville and Italy.
Sharon is survived by his son, Rowland, his daughter, Francesca, and grandchildren, Amelia and Laurie, and his sisters.
• Adam Murdin Silito, visual neurologist, born 31 March 1944; he died 17 December 2023
