Journal of Vision - Cone selectivity derived from the responses of the retinal cone mosaic to natural scenes, by Wachtler, Doi, Lee, & Sejnowski

Thomas Wachtler	Neurophysics Group, Department of Physics, Philipps University, Marburg, Germany
Eizaburo Doi	Institute for Neural Computation, University of California San Diego, San Diego, CA, USA, & Center for the Neural Basis of Cognition, Carnegie Mellon University, Pittsburgh, PA, USA
Te- Won Lee	Institute for Neural Computation, University of California San Diego, San Diego, CA, USA, & Computational Neurobiology Laboratory, Howard Hughes Medical Institute, The Salk Institute for Biological Studies, La Jolla, CA, USA
Terrence J. Sejnowski	Division of Biological Sciences, University of California San Diego, San Diego, CA, USA, & Computational Neurobiology Laboratory, Howard Hughes Medical Institute, The Salk Institute for Biological Studies, La Jolla, CA, USA

To achieve color vision, the brain has to process signals of the cones in the retinal photoreceptor mosaic in a cone-type-specific way. We investigated the possibility that cone-type-specific wiring is an adaptation to the statistics of the cone signals. We analyzed estimates of cone responses to natural scenes and found that there is sufficient information in the higher order statistics of L- and M-cone responses to distinguish between cones of different types, enabling unsupervised learning of cone-type specificity. This was not the case for a fourth cone type with spectral sensitivity between L and M cones, suggesting an explanation for the lack of strong tetrachromacy in heterozygous carriers of color deficiencies.