Predicting visual sensitivity in retinal prosthesis patients Researchers have found that it is possible using a mathematical model to predict the percieved brightness of a wide variety electrical stimulation patterns to the retina delivered by an implanted epiretinal prosthesis.

With the long-term goal of restoring functional vision in patients with retinal degenerative diseases, the eyes of blind human subjects were implanted with epiretinal prostheses consisting of two-dimensional electrode arrays that directly stimulated cells of the neural retina.

In this study psychophysical techniques were then to measure the brightness of electrically generated percepts on single electrodes using a variety of electrical stimulation patterns.

The researchers found that it is possible to predict the sensitivity of the human visual system to a wide variety of retinal electrical stimulation patterns using a simple and biologically plausible model.

This is the first study to demonstrate that, on the single-electrode level, retinal electrical stimulation in humans can produce visual perceptions that are predictable using a quantitative model, a necessary first step for a successful retinal prosthesis.

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Invest Ophthalmol Vis Sci. 2009 Apr;50(4):1483-91.