The Science of Visual Prosthetics - Shelley Fried, PhD and John Pezaris, PhD

In this episode, we cover visual prosthetics, from the 18th-century electrical experiments to today's clinical trials, and why the retina, LGN, optic nerve, and visual cortex each pose unique engineering challenges. We discuss what “phosphenes” are, and the experiments used to determine what patients actually perceive, and what "translating" a camera image into a neural code really means. From there, we look at lessons from cochlear implants and deep brain stimulation, and how they apply to vision, along with the role of private industry and academic research in advancing neurotechnology.

Our guests for this episode are two of the leading figures in visual neuroprosthetics research. Dr. Shelley Fried is a Professor of Neurosurgery at Massachusetts General Hospital and Harvard Medical School, and Director of the Neural Prosthetic Laboratory at MGH. His lab works to improve the effectiveness of CNS-based neural prosthetics by understanding how and why neurons respond to electric stimulation, using that knowledge to develop improved stimulation methods, with projects spanning retinal prosthetics, deep brain stimulation, and other devices.

Dr. John Pezaris is an Assistant Professor of Neurosurgery at Harvard Medical School and Director of the Visual Prosthesis Laboratory at Massachusetts General Hospital. His lab has focused on developing a thalamic visual prosthesis — a machine-brain interface designed to take the output from a digital camera and deliver it directly into the visual parts of the brain, offering a potential therapy for total vision loss.