Blind mice had their vision restored with a device that helped diseased retinas send signals to the brain, according to a study that may lead to new prosthetic technology for millions of sight-impaired people. Current devices are limited in the aid they provide to people with degenerative diseases of the retina, the part of the eye that converts light into electrical impulses to the brain. In research described today in the Proceedings of the National Academy of Sciences, scientists cracked the code the retina uses to communicate with the brain.