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Camera Helps Blind to See
From
ABC News
Man Can Perceive Light and Dark
A blind man known only as "Jerry," who had electrodes implanted in his brain
in 1978, wearing a camera mounted onto a pair of glasses and wired directly
into his brain. (Stephen Chernin/AP Photo)
By Malcolm Ritter
The Associated Press
N E W Y O R K, Jan. 16 — A blind man can read large letters and navigate around
big objects by using a camera wired directly to his brain, the first artificial
eye to provide useful vision, a researcher reports.
The 62-year-old man doesn’t see an image. He perceives up to 100 specks of
light that appear and disappear, like stars that come and go behind passing
clouds, as his field of vision shifts.
But as he showed a reporter last week, that’s enough to let him find a mannequin
in a room, walk to a black stocking cap hanging on a white wall, and then
return to the mannequin to plop the cap on its head. He also can recognize
a 2-inch-tall letter from five feet away, said researcher William Dobelle.
“He can do remarkably well” with the limited visual signal, said Dobelle,
who is developing the artificial vision system.
The man, who asked to be identified only as Jerry, has been blind since age
36. He volunteered for the study and got the brain implant in 1978; scientists
have been working since then to improve the software.
Dobelle is chairman of the Dobelle Institute, a medical device company in
New York. He describes the device and its performance in this month’s issue
of the ASAIO Journal, a publication of the American Society of Artificial
Internal Organs.
Future in Sight?
Richard Normann, who studies artificial vision at the University of Utah,
said he’s encouraged by how much Jerry can do. He said Dobelle’s report suggests
that, someday, even limited signals to the brain will let blind people do
relatively complicated visual tasks.
It’s the first demonstration of useful artificial vision, he said, but he
stressed that the device is “a very limited navigational aid, and a far cry
from the visual experience that normal people enjoy.”
Still, an implant that helps blind people navigate would be a major step forward,
said Dr. Bill Heetderks, who directs a National Institutes of Health program
to develop electronic implants that work with the brain.
“When Dr. Dobelle provides additional details on his methodology that establishes
this result, we may be there,” Heetderks said after reading Dobelle’s report.
While Dobelle’s device uses a brain implant, some other scientists are studying
implants in the retina, the light-sensing tissue at the back of the eye. The
retina strategy made news recently when blind musician Stevie Wonder expressed
interest.
Camera Links to Brain
To use the device, Jerry wears sunglasses with a tiny pinhole camera mounted
on one lens and an ultrasonic range finder on the other. Both devices communicate
with a small computer carried on his hip, which highlights the edges between
light and dark areas in the camera image. It then tells an adjacent computer
to send appropriate signals to an array of small electrodes on the surface
of Jerry’s brain, through wires entering his skull behind his right ear.
The electrodes stimulate certain brain cells, making Jerry perceive the specks
of light. The shifting patterns as Jerry scans across a scene tells him where
light areas meet dark ones, letting him find the black cap on the white wall,
for example.
The device provides a sort of tunnel vision, reading an area about the size
of a card 2 inches wide and 8 inches tall, held at arm’s length.
Jerry uses the device only two or three days a week at Dobelle’s lab while
researchers make adjustments to it. One question is how to improve Jerry’s
depth perception using signals from the range finder. During the demonstration,
Jerry had to walk cautiously as he approached the mannequin and the wall,
holding an arm out to prevent collisions.
Dobelle said an improved version of the device should go on sale overseas,
in limited numbers, later this year. He said Sunday it was not yet clear when
it might be available in the United States.
