title: Nonlinear codes for the yellow/blue mechanism.
abstract: The opponent yellow/blue mechanism is studied by means of an iso-cancellation technique. A qualitative and quantitative analysis of different photopigment models for the yellow/blue code is presented. On the basis of this analysis we provide a new model which ascribes the nonlinear character of the code to a power transformation of the short wave cone activity. This new model leads to predictions concerning the wavelength shift of the short wave component of a unique red. Tests of these predictions support the new model.
mesh_terms: D003118:Color Perception / Q000502:physiology*; D006801:Humans; D008297:Male; D008959:Models, Neurological; D010786:Photoreceptor Cells / Q000502:physiology; D013053:Spectrophotometry