In May 2021, a team of scientists partially restored the sight of a blind volunteer by adding light-sensitive elements to his retina. This technique, called optogenetics, improved the patient’s condition and provided him with blurred vision. Wearing goggles enabled him to have “a ghostly perception of objects in a narrow field of view.” The goggles work by transforming external visual information into amber light that could be recognized by ganglion cells.
The trial, which was the culmination of 13 years of work, offers proof that more effective treatments to restore blindness can be expected in the future. Carl Zimmer’s New York Times article provides a clear and brief summary of the research scientists have conducted since 2008.