Abstract
How do people encode information about color in memory? Prior work suggested that color categories might play an important role, in conjunction with colorimetric properties of the colors to be remembered. The exact role of the observer’s own color vocabulary in memory has been less clear. Here, we report a study of color memory, conducted using calibrated I-Pads, within-subjects, on 10 color-normal observers. First, observers grouped 1625 Munsell colors into categories, providing focal colors and unconstrained color terms for the categories. In a later session, they performed isometric color matches to 5-second stimuli following 10-second and 5-minute retention intervals, with control data taken under simultaneous presentation. Color matches were by the method of adjustment, using a 3-D CIELAB structured color palette. Importantly, observers named the remembered color after each 5-minute trial. Matches were more variable for 10-sec and 5.min delays than in the simultaneous condition and distances from the test color (“bias”) also increased from ∆E=2.8 in the simultaneous condition to about ~∆E=9 in the delay conditions, generally in the direction of increased saturation. Both variability and bias varied across test colors, and both remained approximately constant across the 10-sec and 5-min delays. To test for lexical effects, a novel “attraction score” measured the association between the direction of the remembered color bias and the observer’s personal focal colors. Attraction scores for the pre-experiment color-naming data were modest for most colors, but the 5-min matches were highly significantly attracted to the focal colors of color terms provided after each trial. The color-categorical and lexical properties of the stimuli, as measured before the experiment, were less important than the colorimetric properties of the stimuli and the color names provided afterwards. This suggests that color memory is not strongly related to pre-existing, invariant lexical properties of colors.