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Bodian Seminar: Nicholas J. Priebe, Ph.D.

February 4, 2019 @ 4:00 pm – 5:00 pm

Bodian Seminar:

Nicholas J. Priebe, Ph.D.

Associate Professor

Department of Neuroscience

Center for Learning and Memory

College of Natural Sciences

University of Texas Austin

“Active Sensation for Vision”

Humans and other primates sample the visual environment using eye movements that shift a high- resolution fovea towards regions of interest to construct a clear perception of a scene across fixations. Many mammals, however, like mice, lack a fovea, which raises the question of why they make saccades. I describe and test the hypothesis that eye movements work in concert with the adaptive properties of neural networks. Eye movements provide many individual visual neurons with new input regardless of the presence of a fovea. When afoveal animals make eye movements, the resolution of the neural representation of the visual scene at each location does not change, but which specific neurons are stimulated does change. Visual neurons are sensitive to such changes, which often lead to large transient responses. Using a combination of analytical and computational models, we have quantified the relationship between response gain and the impact of shifting versus maintaining gaze. Shifting gaze results in increased spike rate across the neuronal population and those increases are largest for saccades that move RFs into regions of the scene that are uncorrelated with previous regions.