*** 9713365 Litke This grant will support the initial development of a system to study how the retina process and encodes a visual image. This "Retinal Readout System" will allow the simultaneous detection of signals from thousands of output cells in live retinal tissue as a visual image is focused on the cells. The signals from the output neurons will be detected in real- time, in a single retinal preparation, with all spatial and temporal correlations recorded. This system will be based, in large part, on technology developed in the field of high energy physics for the study of short-lived particles: the technology of silicon microstrip detectors. The silicon detector techniques to implement the Retinal Readout System include: high-density wire-bonding, custom-designed analog VLSI readout chips, and fast data acquisition. The specific items to be developed include a variety of electrode arrays for the detection of the retinal signals, a prototype VLSI chip (the "Neurochip") for reading out the electrode arrays, and a fast data acquisition system based on an analog-to-digital converter module installed in a PC. ***
