Artificial Vision: Can Brain Implants Make the Blind See?

Once upon a time the idea of artificial vision was nothing more than science fiction. Colonel Steve Austin, the Six Million Dollar Man, had his bionic eye. Lieutenant Commander Geordi La Forge had his special visors that allowed him to see, although not in the way a normal person sees.

Artificial vision is now starting to become a reality, if slowly. Like the visor of Geordi La Forge, this artificial vision does not allow the blind to see as we might expect them to, but it gives them vision in a totally new if limited capacity.

A Camera, a Brain Implant and a Computer

In the year 2000 it was revealed that a man identified only as Jerry had the first functional electronic eye. In tests he was able to pick up a black hat from a white wall and subsequently place the hat on the head of a mannequin. He recognized a two inch tall letter E lying on its back from a distance of five feet. He was also able to navigate a New York subway with the assistance of his artificial vision.

Jerry, who was one of the first two subjects to receive the brain implants in 1978, successfully demonstrated that this limited artificial vision could serve as an aid to the blind. Never before had such a feat been accomplished.

His artificial implants do not give him anything like what we normally conceive of as vision. Jerry sees up to a hundred points of light (called posphenes), displayed against a black background. Its appearance has been likened to a field of stars in the night sky or the lights which are displayed on an electronic scoreboard.

Using this visual information Jerry is able to navigate his surroundings (if cautiously) and discern certain physical objects, as displayed in the testing results.

In order to achieve this feat Jerry sports a pair of sunglasses. On one the left lens of the glasses is an ultrasonic receptor, used to gauge distance. On the right lens is a tiny video camera. The data obtained by the glasses is then sent to a computer worn on his back. The computer processes the data then sends the information to 68 electrodes implanted in the brain at the back of the skull. All in all the apparatus weighs about 10 pounds.