David H. Hubel, whose discoveries in visual processing and development ushered in the modern study of the cerebral cortex and changed the way childhood cataracts and strabismus (“cross-eye”) were treated, died on Sept. 22, 2013, of kidney failure in Lincoln, Mass. He was 87.
Hubel, the HMS John Franklin Enders Professor of Neurobiology, Emeritus and longtime research partner Torsten Wiesel shared half of the 1981 Nobel Prize in Physiology or Medicine for their groundbreaking insights into the structure and function of the visual cortex and the importance of exposure to certain visual stimuli shortly after birth for normal vision development. (The other half of that year’s prize went to Roger Sperry for finding that the two hemispheres of the brain have specialized functions.)
“David was one of the great scientists of his generation,” said Michael Greenberg, Nathan Marsh Pusey Professor of Neurobiology and chair of the Department of Neurobiology at HMS. “His work revealed how the brain is organized to produce visual perception. The insights we have gained from his discoveries resonate to all aspects of sensory perception. Not only were his experimental findings revolutionary, David was also a passionate teacher and a talented communicator. Everyone in the field of neurobiology has been inspired by his achievements.”
Even by the 1950s, little was understood about how the brain transforms electrical signals from the eyes into an image, or how the visual cortex—the area of the brain responsible for processing vision—is structured. Many scientists thought visual information was simply projected point by point into the cortex, like a movie screen.
In what fellow Nobel laureate Eric Kandel once called “one of the most remarkable, sustained and productive collaborations in contemporary science,” Hubel and Wiesel revealed the complexities of visual perception across 25 years of seminal publications.
They identified the sequence of visual processing in cats, laying the foundation for understanding how visual cues are broken down and reconstituted as they travel through the brain.
They described how different neurons respond to highly specific visual cues—for example, some activate at the presence of horizontal lines, others at vertical lines, others at particular axes in between—and showed that neurons with similar functions are arranged together in columns. They also showed that neurons are organized into columns based on whether they receive information from the right or left eye (their “ocular dominance”), which contributes to binocular vision.
In addition to revealing that the visual cortex has an organized structure that corresponds to cell function, Hubel and Wiesel provided the first direct evidence that sensory deprivation in early childhood can alter that structure. In one experiment, they observed that if one eye remains closed for a period of time after birth, the corresponding area in the visual cortex permanently atrophies.
The finding led to a recommendation that strabismus should be treated before age 2, while the brain is still able to adapt to the adjusted eye position. It also provided insight into the understanding and treatment of conditions such as deprivation amblyopia (“lazy eye”) and childhood cataracts.
In 1978, Hubel, Wiesel and mentor Vernon Mountcastle of Johns Hopkins University received the Louisa Gross Horwitz Prize from Columbia University Medical Center for their discoveries.
Hubel was born in 1926 in Windsor, Ontario, Canada, to American parents. He credited his interest in science to his father, a chemical engineer and pharmacist.
The family moved to Montreal in 1929, where Hubel developed hobbies in chemistry and electronics. In his Nobel Prize biography he recalled tiring of electronics “because nothing I built ever worked.” He played with chemical mixtures instead, setting off a small cannon and launching a hydrogen balloon that sailed 100 miles away to the town of Sherbrooke.
In 1947 he graduated from McGill College with honors in mathematics and physics, which he claimed to have studied “partly to find out why nothing worked in electronics, but mainly because it was more fun to do problems than to learn facts.” He applied to medical school at McGill despite almost no biology education and was accepted “rather to my horror.”
Hubel became fascinated by the nervous system and headed to Johns Hopkins University School of Medicine for an assistant residency in neurology. He was promptly drafted by the U.S. Army as a doctor and stationed at Walter Reed Army Institute of Research. There he invented two tools—a hydraulic microdrive and a tungsten microelectrode—that allowed him to study the firing of individual neurons in the visual cortex of both waking and sleeping cats.
In 1958 Hubel returned to Hopkins and joined the lab of Stephen Kuffler, who introduced him to Wiesel and encouraged them to work together. One year later Kuffler’s lab moved to Harvard Medical School, where Wiesel remained until 1983 and Hubel for the rest of his career.
By the time of Wiesel’s departure Hubel had begun collaborating with HMS neurobiology professor Margaret Livingstone in visual illusions and the parallel processing of visual images.
“I will miss him. All of us in my lab, my department, my field and science in general, will miss him, but he lives on in what he discovered and in all of us whom he taught and influenced,” said Livingstone. “Whenever I teach someone, think about a question or a result, or am writing, he is very much part of it.”
Outside the lab, Hubel enjoyed a variety of hobbies, including music—he played the piano, recorder and flute, and met his wife, Ruth, in a university choral society—foreign languages, woodworking, photography, astronomy, skiing, tennis and squash.
He is survived by three sons and four grandchildren.
Related Journal Articles:
David Hubel: In Memoriam. Margaret Livingstone. Neuron, October 16, 2013.