Digital eye offers promise for blind

Copyright  2000 Associated Press

By: Malcolm Ritter

NEW YORK (January 17, 2000 6:59 a.m. EST http://www.nandotimes.com) -
To the blind man with a tiny camera wired to his brain, the world looks like
dozens of scattered stars twinkling on and off. 

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 can also recognize a 2-inch-tall letter from five feet away, said
researcher William Dobelle. 

The man's performance is the first demonstration that an artificial eye can
provide useful vision, said Dobelle, who's developing the device. 

"He can do remarkably well" with the limited visual signal, Dobelle said. 

Dobelle is chairman of the Dobelle Institute, a medical device company in New
York. He described the device and its performance in this month's issue of
the ASAIO Journal, a publication of the American Society of Artificial
Internal Organs. 

Richard Normann, who studies artificial vision at the University of Utah,
said he's encouraged by how much the blind man can do. The new report
suggests that someday, even limited signals to the brain will let blind
people do relatively complicated visual tasks, he said. 

It's the first demonstration of useful artificial vision, he said, but he
stressed the device is still "a very limited navigational aid, and it's a far
cry from the visual experience that normal people enjoy."  

Doctor Bill Heetderks, who directs a National Institutes of Health program to
develop electronic implants that work with the brain, said an implant that
helps blind people navigate would be a major step forward. 

"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 retina strategy made news recently when
blind entertainer Stevie Wonder expressed interest. 

Dobelle's patient, who asked to be identified only as Jerry, has been blind
since age 36. Now 62, he volunteered for the study and got the brain implant
in 1978; scientists have been working since then to improve the software. 

To use the device, Jerry wears sunglasses with the 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 lab wall, for example. 

The device provides a sort of tunnel vision. At any one time, it can cover 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, as
researchers tinker with it. One question is how best to provide depth
perception, using signals from the range finder. Jerry had to walk cautiously
as he approached the mannequin and the wall during the lab demonstration,
with an arm out to prevent collisions. 

Dobelle said an improved version of the device should go on sale overseas in
limited quantities this year. It's not clear when it might become available
in the United States, he said.


http://www.dobelle.com/vision/asaio1.html
