Abstract
Basic color categories show strong shared tendencies among linguistic groups, yet the focal stimuli chosen as best examples of these basic colors vary significantly across both individuals and populations. The causes of these differences are not known. We examined the extent to which variations in color appearance could be attributed to variations in the individual's color environment, by modeling how color appearance should change when observers are adapted to different environments. The adaptation was modeled as gain changes in the cones and in multiple post-receptoral channels tuned to different combinations of luminance and chromatic contrast. Channel responses were tabulated for images sampled from different environments and then rescaled so that the average response within each channel was equal across two environments. Shifts in perceived hue were assessed by determining the different stimuli required to produce the same response ratios in the different adaptation states. Rendering images with these adapted responses simulates how the world might appear to the same “observer” when they are under theoretically complete adaptation to different environments, and these effects are illustrated with images of the Munsell palette used in the World Color Survey. Adaptation to different natural color contexts significantly shifts color foci, yet these are primarily confined to changes within rather than between categories. We compare these predicted variations to the population differences actually observed in the World Color Survey, which similarly exhibit primarily within-category shifts in mean foci. Our analysis shows that even observers with a completely shared biology may experience color in significantly different ways because of adaptation to different environments, and provides both a measure of the theoretical extent of environmental influences on color naming and a novel way of simulating how the world might look to others.