Psychophysics-Guided Signal Processing for Retinal Prosthetics

Duke University, Durham NC

Investigators

Abstract

Abstract Photoreceptor degenerative diseases are the leading cause of blindness in the elderly in the USA. Recent advances in the development of bionic eyes have provided some visual function to blind patients. In bionic eyes, an externally-worn camera captures images from the field-of-view. These images are transferred to a microprocessor that compresses the camera's information and converts the data to electronic signals, which are then transmitted to an implantable retinal prosthesis. The image resolution experienced by these patients is limited by the number of implanted electrodes on the retina, which are analogous to camera CCD pixels. Our long-term goal is to improve the vision outcome of patients with implanted retinal prostheses through software without any hardware modification. The overall objective of this proposal, which is a step towards attaining our long-term goal, is to define the mathematical and psycho-visual foundations required for designing software that takes advantage of the brain's image-fusion and enhancement processes. In this need-driven proposal, we hypothesize that by processing the externally-worn camera's information, i.e. introducing spatial and temporal modifications to the captured images before transferring them to the electrodes, we can significantly improve the quality of vision experienced by the patients with implanted retinal prostheses. We will develop such an optimal information processing system and we will perform pilot experiments to assess its effectiveness. We believe the outcome of this study has the potential to cause a paradigm shift in the design of bionic eyes and will provide better functional vision to patients with implanted retinal prostheses.