In this issue of the JCI, the dream of restoring useful vision to blind individuals with
neurotechnology moves one step closer to realization. Fernández et al. implanted an
electrode array with 96 penetrating electrodes in the visual cortex of a blind patient who had
been without light perception for 16 years due to optic neuropathy. Remarkably, the patient
was able to perceive visual patterns created by passing current through array electrodes.
The use of a penetrating electrode array meant that action potentials from single neurons …

BACKGROUND. A long-held goal of vision therapy is to transfer information directly to the
visual cortex of blind individuals, thereby restoring a rudimentary form of sight. However, no
clinically available cortical visual prosthesis yet exists. METHODS. We implanted an
intracortical microelectrode array consisting of 96 electrodes in the visual cortex of a 57-year-
old person with complete blindness for a 6-month period. We measured thresholds and the
characteristics of the visual percepts elicited by intracortical microstimulation. RESULTS …