This is a project to study how the retina processes and encodes visual images. The retina is an exquisite, but complex, optical image detector that converts an input light image into a set of highly processed sub-images. Each sub-image is generated, and transmitted to the brain, along a separate, but parallel, neural pathway. The aim of this project is to study the properties of these sub-images. The Retinal Readout System (RRS), based on two-dimensional arrays of microscopic electrodes, has been developed by an interdisciplinary team with expertise in high energy physics, neurobiology, nanofabrication, and VLSI design to help answer these questions. The RRS can record simultaneously from several hundred retinal output neurons while the retina is stimulated by a dynamic visual image, focused on the input neurons. This represents an order-of-magnitude leap over the existing technology, with further improvements possible. Pilot data taken with guinea pig and monkey retina have verified that the RRS works, with approximately 500 neurons recorded in single preparations.
Although the emphasis of the project is on the study of retinal processing, the instrumentation developed is extremely versatile. It represents a comprehensive solution for the large-scale recording of neural activity, in terms of both hardware and software. It can image and record neural activity with good time, amplitude, and spatial resolution, over an extended period of time, from hundreds of neurons. These properties give it the potential for wide application in other areas of neuroscience.
The project has provided, and will continue to provide, research opportunities for undergraduate students, graduate students and postdoctoral researchers, in both physics and biology. These opportunities have ranged from independent study courses to senior thesis and Ph. D. thesis work.
This project is supported by the Physics Division and by the Office of Multidisciplinary Activities in the Mathematical and Physical Sciences Directorate.
