Continuous dynamics of color categorization

In order to assess whether color categorization is sensitive to within-category differences in hue, we monitored mouse trajectories in a modified categorization task. Participants saw color swatches from a blue-green continuum and categorized them with a computer mouse by selecting one of two colored regions at the top of a monitor. An analysis of the mouse trajectories showed that the deviation toward the competing category was a function of hue: As hues approached the category boundary, they increasingly deviated to the competitor. This work presents evidence for parallel activation on the level of hue and category processing for color, as well as simultaneous activation of perceptually adjacent categories. Thus, a dynamic process sensitive to fine-grained within-category detail best characterizes color categorization.