Self-organization of color opponent receptive fields and.pdf

Self-organization of color opponent receptive fields and laterally connected orientation maps James A. Bednar 1 , Judah B. De Paula and Risto Miikkulainen Department of Computer Sciences, The University of Texas at Austin {jbednar,judah,risto}@ 1 Present address: School of Informatics, University of Edinburgh, jbednar@inf.ed.ac.uk Abstract Long-range lateral connections in the primary visual cortex (V1) are known to link neurons with similar orientation preferences, but it is not yet known how color-selective cells are connected. Using a self- organizing model of V1 with natural color image input, we show that realistic color-selective receptive fields, color maps, and orientation maps develop. Connections between orientation-selective cells match previous experimental results, and the model predicts that color-selective cells will primarily connect to other cells with similar chromatic preferences. These findings suggest that a single self-organizing system may underlie the development of orientation selectivity, color selectivity, and lateral connectivity. Key words: Color maps, Orientation maps, Color blobs, Red-green receptive fields, Opponent cells 1 Introduction Most simple cells in the primary visual cortex (V1) are selective for the orientation of a stimulus, but many are also selective for particular colors [12]. Recent experimental results have shown for the first time how these color-selective cells are organized at the map level, and how they relate to other visual maps such as orientation or ocular dominance [11]. In addition to their afferent input from the LGN, the neurons in these maps are connected in- tracortically through specific long-range lateral connections [10]. The lateral connections have been found to link cells with similar orientation preferences [6, 10], which allows suppressing redundancy in the input and improves the cells’ ability to detect changes in a stimulus [4, 14]. However, the role of these connections in the development and a