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Blind man can see thanks to
a camera implanted in his brain
 He
could be the first cyborg of history.
A man, who asked to be identified only as Jerry, has been blind
since age 36. Now 62, he volunteered for the study and got a brain
implant in 1978.
Wires have been connected with the cortex of his brain, in the
area reserved to processing visual information. A camera can be
connected to such wires. There has been no infection or rejection
in the past 23 years.
Scientists have been working since then to develop and improve
the software that enables Jerry to use the device as a primitive
visual system. To use the it, 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 lab wall, for example.
The results are not as impressive as Robocop, but he can recognize
a 2-inch-tall letter from five feet away. It can only cover an area
about the size of a card 2 inches wide and 8 inches tall, held at
arm's length.
However the man's performance is the first demonstration that an
artificial eye can provide useful vision, said William Dobelle,
who's developing the device. "He can do remarkably well" with the
limited visual signal.
Dobelle is chairman of the Dobelle Institute, a medical device company
in New York. He described the device and its performance in an issue
of the ASAIO Journal, a publication of the American Society of Artificial
Internal Organs.
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