Bruno Olshausen (University of California, Davis): Sparse coding as a principle of image representation in visual cortex.

I shall discuss the principle of sparse coding as it has been applied toward modeling the response properties of V1 neurons. I shall also present evidence from functional magnetic resonance imaging showing that activity in V1 is reduced as a result of perceptual grouping. These results together with the modeling studies suggest that cortical neurons attempt to provide a succinct description of the structures in natural scenes using a small number of active units.