A stimulation platform for optogenetic and bionic vision restoration

Optogenetic therapy holds the promise to restore visual function in patients affected by retinal degenerative diseases. However, the light-sensitivity of the molecule mediating light responses is much less than the one of healthy retinal cells so that no photo-stimulation is expected under natural environmental conditions. In this work, we present a platform set up to stimulate optogenetically-engineered retinal cells, and the algorithms associated with different types of stimulation. The system consists of a neuromorphic silicon retina as a visual frontend, a projecting device capable of delivering fast and precise light stimulation and a computing platform implementing the stimulation algorithms. We describe different strategies, varying depending on the type of cells transfected. The silicon retina provides a natural front-end for an artificial visual system, complying with the information encoding principles, timing properties and dynamic range of either photoreceptors or RGCs. The encoding of the visual information is performed with sub-millisecond accuracy, respecting the temporal characteristics of the neural system. The platform and algorithms hereby presented provide a basis for medical devices matching the requirements of optogenetic therapeutic use. An embedded version of this platform will be used in the forthcoming clinical trials of the GS030 vision restoration therapy.