A new prosthetic device can translate the external visual world into patterns of electrical pulses similar to those produced by the normal retina, restoring sight to blind mice (Nirenberg S and Pandarinath C. Proc Natl Acad Sci U S A. doi:10.1073/pnas.1207035109 [published online August 13, 2012]).
The advance is based on an understanding of how visual signals in the eye are translated into a code of electrical pulses that pass from cell to cell and finally reach the ganglion cells that communicate with the brain.
Hampton T. Retinal Prosthesis for Blindness. JAMA. 2012;308(13):1310. doi:10.1001/jama.2012.13155