David Hubel, Nobel-Winning Scientist, Dies at 87
By DENISE GELLENE
Published: September 24, 2013
Dr. David Hubel, who was half of an enduring scientific team that won a Nobel Prize
for explaining how the brain assembles information from the eye’s
retina to produce detailed visual images of the world, died on Sunday in
Lincoln, Mass. He was 87.
Associated Press
The cause was kidney failure, his son Carl said.
Dr. Hubel (pronounced HUGH-bull) and his collaborator, Dr. Torsten Wiesel,
shared the 1981 Nobel in Physiology or Medicine with Roger Sperry for
discovering ways that the brain processes information. Dr. Hubel and Dr.
Wiesel concentrated on visual perception, initially experimenting on
cats; Dr. Sperry described the functions of the brain’s left and right
hemispheres.
Dr. Hubel’s and Dr. Wiesel’s work further showed that sensory
deprivation early in life can permanently alter the brain’s ability to
process images. Their findings led to a better understanding of how to
treat certain visual birth defects.
Dr. Hubel and Dr. Wiesel collaborated for more than two decades,
becoming, as they made their discoveries, one of the best-known
partnerships in science.
“Their names became such a brand name that H&W rolled off the tongue
as easily in the lab as A&W root beer did at lunch,” Robert H.
Wurtz, a neuroscientist, wrote in a review article about their work.
Before Dr. Hubel and Dr. Wiesel started their research in the 1950s,
scientists had long believed that the brain functioned like a movie
screen — projecting images exactly as they were received from the eye.
Dr. Hubel and Dr. Wiesel showed that the brain behaves more like a
microprocessor, deconstructing and then reassembling details of an image
to create a visual scene.
By measuring the electrical impulses of cells in the visual cortex, the
scientists discovered that cells respond to straight lines, movement and
contrast — features that delineate objects in the environment. They
further found that some cells fire rapidly in response to horizontal
lines, while other cells prefer vertical lines or angles. Cells with
similar functions are organized into columns, they said, tiny
computational machines that relay information to a higher region of the
brain, where a visual image is formed.
Dr. Hubel and Dr. Wiesel also found that vision does not develop
normally if the brain fails to make connections with the eye during a
critical window early in life.
In a 1962 experiment, the scientists showed that kittens that had one
eye sewn shut after birth became blind in that eye because their brains
were deprived of visual stimulation. In a related experiment, the
scientists showed that exposure to light did not by itself provide
enough stimulation; it was necessary for newborn animals to see the
patterns and contours of the world around them.
Doctors now operate on infants born with cataracts early in life to
prevent vision loss; before Dr. Hubel’s and Dr. Wiesel’s research,
doctors removed cataracts from infants between ages 6 months and 24
months, with poor results. The research also led to earlier treatment
for strabismus, a condition in which the eyes are not properly aligned.
Scientists have since found evidence of similar “critical periods” in hearing and language acquisition.
“David and Torsten did more than open up the study of the primary visual
cortex; they laid the basis of all that was to follow in the sensory
systems,” Dr. Eric R. Kandel, a Nobel laureate, wrote in a recent
commentary about their research. “Together this body of work stands as
one of the great biological achievements of the 20th century.”
David Hunter Hubel was born in Windsor, Ontario, on Feb. 27, 1926, to
American parents. His father was a chemical engineer. Dr. Hubel grew up
in Montreal, where his boyhood hobbies included chemistry. He once
rocked his neighborhood by firing a small cannon in the middle of his
street; in another experiment, he launched a hydrogen balloon that was
found by a farmer’s daughter 100 miles away.
He went to McGill University, where he studied math and physics because
he preferred solving problems to memorizing facts. But after earning his
bachelor’s degree in 1947, he decided against a career in mathematics.
“To make it in that field required a virtuosity — like becoming a
concert pianist — that I probably lacked,” he told an interviewer.
Thinking he might like to do medical research, he went on to medical
school at McGill and soon found himself straining to remember every
muscle in the body. But he got to spend summers at Montreal Neurological
Institute, where he became fascinated with the nervous system.
After receiving his medical degree in 1951, he studied neurology at
McGill for three years before heading to Johns Hopkins University in
Baltimore for a neurology fellowship. The Korean War interrupted his
plans.
He was drafted into the United States Army and assigned to the
neuropsychiatry division at Walter Reed Army Institute of Medical
Research, where his efforts soon turned to the visual system. He
developed an implantable tungsten electrode and a method for using it to
measure the firing of brain cells in cats as they watched a moving spot
on a screen. He found that cells were very selective; they fired when
the spot moved in one direction but not another. Some cells did not fire
at all.
Dr. Hubel’s Army service ended in 1958, but he could not immediately
resume his Johns Hopkins fellowship because the laboratory that had
recruited him was being remodeled. Another Johns Hopkins neurologist,
Dr. Stephen Kuffler, impressed with Dr. Hubel’s work at Walter Reed,
invited him to spend a year in his lab. Dr. Kuffler paired Dr. Hubel
with another young scientist interested in vision, Dr. Wiesel.
In 1959, the scientists were recruited with their mentor to Harvard
Medical School, where Dr. Hubel spent the rest of his career. He
maintained his lab well past his official retirement, and until January
taught a freshman seminar, in which students learned to use soldering
irons to build biomedical instruments, and received training in surgical
techniques.
His wife, Ruth, died in February. In addition to his son Carl, Dr.
Hubel’s survivors include two other sons, Eric and Paul, and four
grandchildren.
Dr. Hubel and Dr. Wiesel liked to recall that their initial discovery
about how vision works resulted from luck. Working in a tiny basement
laboratory at Johns Hopkins, the pair struggled for days to coax brain
cells in cats to respond to images of dark and light spots. Becoming
increasingly frustrated, they waved their arms, jumped around, and, in a
moment of levity, displayed images of glamorous women from magazines.
Then, as they shifted a slide in the opthalmoscope, a cell in the cat’s
visual cortex suddenly started to fire. The edge of the slide had cast a
straight, dark line on the animal’s retina. “It was what the cell
wanted, and it wanted it, moreover, in just one narrow range of
orientations,” Dr. Hubel said in his Nobel lecture.
They studied the cell for nine hours, and then, Dr. Wiesel recalled, ran down the hall screaming with joy.
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