By Margaret Harris at the AAAS meeting in San Jose
“Restoration of sight to the blind” is a brave claim, one with an almost Biblical ring to it. For Daniel Palanker, though, it is beginning to look as if it is an achievable goal. A medical physicist at the University of Stanford, Palanker has developed a prosthetic vision system that replaces damaged photoreceptors in the retina with an array of tiny photodiodes. When infrared images are projected onto this array, the photodiodes convert the light pulses into electrical signals, which are then picked up by the neurons behind the retina and transmitted to the brain. The result is an artificially induced visual response that, while not as good as normal vision, could nevertheless provide “highly functional restoration of sight” to people with conditions such as retinitis pigmentosa or age-related macular degeneration (AMD).