Individual differences in color constancy with cube stimuli

Large individual differences in color perception, such as those observed in #TheDress and #TheShoe, highlight a fundamental challenge in visual perception: how humans infer surface colors from images with ambiguous chromatic information. When the relationship between surface reflectance and illumination cannot be uniquely determined, observers may arrive at different perceptual interpretations of the same image. This project investigates whether the dimensionality of chromaticity distributions in images contributes to such inter-observer variability. Many well-known ambiguous images exhibit chromaticity distributions that are approximately one-dimensional, for example elongated along the daylight locus or along complementary color axes. This has led to the hypothesis that limited chromatic diversity increases ambiguity and amplifies individual differences in perceived color. To examine this idea, we systematically manipulate the dimensionality of chromaticity distributions using controlled, computer-rendered stimuli. By varying the number and arrangement of surface colors within a simple geometric scene, we create stimuli with chromaticity distributions ranging from one-dimensional to two-dimensional. Observers’ categorical color judgments are then measured as the overall chromaticity of the stimulus is gradually shifted along defined color axes. Through this approach, the project aims to clarify whether chromaticity dimensionality is a key factor underlying individual differences in color perception, and to deepen our understanding of how the visual system resolves ambiguity in color appearance from limited image information.