One of the great challenges of neuroscience is to understand how nerve cells act synergistically to create perception, thought, and emotion. The PI has for the last 16 years directed the Boston Retinal Implant Project, the goal of which is to develop a prosthesis to restore vision to the blind. An extrapolation of this work strongly suggests that even a perfectly engineered device will not succeed in producing high quality vision. The missing factor is the knowledge of how to communicate with the central nervous system, of which the retina is a part. The neural code is complex; developing insights into its properties will occur gradually, and over a much longer period of time than this grant will cover. The PI's goals for this phase of the project are to develop platform technologies to advance the study of neural coding, and to perform learning experiments that will provide new information about the natural coding of the visual system and how artificial stimuli can be delivered to emulate natural responses. Using the existing strengths of his research group, the PI will build devices that will make it possible to record and wirelessly transmit neural responses from large regions of the retina or brain, with the ultimate goal of capturing these responses in awake animals as they roam freely within a test environment. Computational strategies will be used to compare neural responses that are generated by stimulating the retina with light to those generated by stimulating the retina with electricity delivered in the same geometric patterns. Learning algorithms will be used to adjust the patterns of electrical stimulation to emulate the natural light-induced responses. Collectively, these studies will provide new insights into properties of neural coding and how the natural responses of the brain can be emulated to create vision, and take us a few steps further along the path toward restoration of function to disabled patients.
Broader Impacts: This work will increase the probability that a retinal prosthesis will one day restore useful vision to blind patients. Many millions of patients with age-related macular degeneration and another 1.6 million with retinitis pigmentosa suffer from blindness because of a relatively selective loss of photoreceptors. A retinal prosthesis could restore vision to such patients by directly stimulating the nerve cells that connect the eye to the brain. This hope will be realized only if proper communication strategies to deliver visual information to the brain are learned. This research will also train students in engineering and biomedical disciplines who will contribute to the emerging fields of neural coding, brain-machine interfaces and the science of learning.
