The October 2014 UWIN Seminar will be held on Tuesday, October 14th at 2pm in Foege S060 and will feature Sebastian Seung of Princeton University, an eminent researcher in neural computation and a pioneer of connectomics.

His talk will be entitled “Space-time wiring specificity supports direction selectivity in the retina”.

Description: The perception of motion is a basic visual ability, and already begins in the retina. Some retinal outputs (ganglion cells) respond selectively to stimuli moving in particular directions, but retinal inputs (photoreceptors) are not direction selective (DS). How does DS emerge from the microcircuitry connecting inputs to outputs? In search of clues, we reconstructed starburst amacrine cells (SACs) and bipolar cells (BCs) in serial electron microscopic images with help from EyeWire, an online community of volunteer neuroanatomists. Based on quantitative contact analyses, we found evidence that the two ends of each SAC dendrite are wired to BC types with different time lags in visual response. A mathematical model shows how such “space-time wiring specificity” could endow SACs with receptive fields that are oriented in space-time, and hence with visual responses selective to direction of motion.