Visual Prostheses

Abstract

Since the mid-1700s, humans have been trying to restore vision to the blind. The first attempts involved gross application of electric shock to the skull [LeRoy, Hist. Acad. Roy. Sci. (Paris), Mémoires Math. Phys. 60, 87–95 (1755); Marg, Optom. Vis. Sci. 68, 427–440 (1991)]. While unsuccessful, these efforts utilized the same principles employed by modern-day visual prostheses. Electrical current, substituted for light, is delivered to cells along the visual pathway in order to create the sensation of vision. Visual prostheses have indeed come a long way since their inception in the eighteenth century. They have enabled blind individuals to perceive light and perform simple visual tasks. Given the current state of the technology, it is not unreasonable to suggest that within the next 10–20 years, people with implants who were once blind will be reading small print and recognizing faces.