Neurobiologist and vision expert Denis Baylor dies at 82

Baylor, former chair of the Department of Neurobiology, gained international recognition for discovering the electrical language used by the retina to translate light from the outside world into signals that the brain reads.

- By Genevieve Bookwalter

Denis Baylor in Kapalua, Maui. He became an avid golfer after retirement.
Eileen Baylor

Denis Baylor, MD, a professor of neurobiology who explained how the human eye converts light into electrical signals that the nervous system can read, died March 16 following a heart attack at the Stanford Golf Course. He was 82.

“Denis was a neurobiologist extraordinaire,” said William Newsome, professor of neurobiology, the Harman Family Provostial Professor and the Vincent V.C. Woo Director of the Wu Tsai Neurosciences Institute.

Baylor’s research established the specific biological basis that modern color technology — including TVs, printers and LCD screens — relies on. “These technologies depend on knowing how the human eye absorbs, reacts to and processes color,” Newsome said. Baylor “was just trying to solve a fundamental problem about nature, and that’s the way the best scientists are motivated,” he added.

In 1977, Baylor’s lab pioneered a technique for examining the function of individual retinal cells — the rods and cones. It was more sensitive than other methods of the time because it could measure sensitivity to all the wavelengths in the visible part of the spectrum rather than simply measuring whether light is absorbed by the cell.

“Denis Baylor’s truly trailblazing research provided insights and answers related to a fundamental question in neurobiology: How does the eye allow us to see?” said Lloyd Minor, MD, dean of the School of Medicine. “Moreover, he was a profoundly dedicated teacher who delivered engaging lectures and worked tirelessly to uplift his students.”

Carla Shatz, PhD, professor of biology and neurobiology, the Catherine Johnson Holman Director of Stanford Bio-X, and the Sapp Family Provostial Professor, called her 1991 collaboration with Baylor “one of the most rewarding and exciting experiences of my entire scientific career.” Their work led to the discovery of spontaneous wave activity in the developing mammalian retina.

“Denis was a superb mentor and collaborator,” said Lubert Stryer, MD, professor of neurobiology, emeritus. “Many outstanding vision scientists spent their formative years in association with him and were inspired by his creativity, rigor, insight and generosity of spirit.”

Denis Baylor

An inspiring teacher

Baylor was born Jan. 30, 1940, in Oskaloosa, Iowa, and grew up in Galesburg, Ill. He graduated from Knox College in 1961 and from Yale Medical School in 1965. He served on the faculty of the University of Colorado School of Medicine before moving to Stanford in 1974.

He became a full professor in 1978, serving as chair of the neurobiology department from 1992 to 1995, and retired in 2001. Before and after retirement, he served on a number of scientific advisory boards and was a member of the Wu Tsai Neurosciences Institute.

His colleagues remembered him as an inspiring teacher who took pride in his students’ work and set the standard for delivering lectures.

Brian Wandell, PhD, professor of psychology and the Isaac and Madeline Stein Family Professor, who hosted Baylor in his class each year, said, “His experiments were magnificent, and so were his lectures. He was the most precise lecturer any of us ever saw! Each word, each graph, each idea carefully chosen and organized.”

He was the most precise lecturer any of us ever saw! Each word, each graph, each idea carefully chosen and organized.

He was the most precise lecturer any of us ever saw! Each word, each graph, each idea carefully chosen and organized.Newsome remembered stopping by the office to check his mail one Saturday morning and hearing a voice from a nearby conference room. It was Baylor.

“I said, ‘Denis, what are you doing?’ And he said, ‘I’m practicing my neurobiology lecture for Monday afternoon.’ I said, ‘Denis, you’ve been giving this lecture on phototransduction for 10 years now. Can’t you look over your notes and go give the lecture?’” Newsome recalled.

“He crossed his arms and looked at me very seriously and said, ‘Yes, I could do it that way, Bill, and it would be very efficient. And somewhere in the middle I would make a mistake and I would say Baylor, you’re screwing it up, and it’s your own darn fault because you didn’t practice this thing.’”

Helping students “have a crystal-clear understanding of what we knew about transduction was the intellectual passion of his life,” Newsome said.

Football devotee, avid golfer

While his academic rigor was legendary, Baylor also was remembered as a down-to-Earth, small-town Midwesterner who was passionate about Stanford football and, in retirement, his golf game.

“Stanford football was a big deal,” chuckled his wife, Eileen Baylor. “He used to go to pregame briefings, if you can believe it. It’s true! Two hours ahead” of kickoff.

For a time, Baylor’s hobby was woodworking, and “he made many, many pieces of furniture,” his wife recalled.

He also enjoyed golf, she said. “He approached golf like he approached his work. He kept a journal every time we played.” He was “a true scientist. We’re talking years of logs. It’s not just one log.”

Eileen Baylor said she was glad she was with her husband on the day he died, playing the game he loved with her and a friend.

“We were on the 12th hole, and Denis was walking when he collapsed and couldn’t be revived,” she said.

Besides his wife, Baylor is survived by brothers Michael and Stephen Baylor; sons Denis and Michael Baylor; daughter Michele Engelke; and nine grandchildren.

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