Memory color of natural familiar objects: Effects of surface texture and 3-D shape

Abstract

Natural objects typically possess characteristic contours, chromatic surface textures, and three-dimensional shapes. These diagnostic features aid object recognition, as does memory color, the color most associated in memory with a particular object. Here we aim to determine whether polychromatic surface texture, 3-D shape, and contour diagnosticity improve memory color for familiar objects, separately and in combination. We use solid three-dimensional familiar objects rendered with their natural texture, which participants adjust in real time to match their memory color for the object. We analyze mean, accuracy, and precision of the memory color settings relative to the natural color of the objects under the same conditions. We find that in all conditions, memory colors deviate slightly but significantly in the same direction from the natural color. Surface polychromaticity, shape diagnosticity, and three dimensionality each improve memory color accuracy, relative to uniformly colored, generic, or two-dimensional shapes, respectively. Shape diagnosticity improves the precision of memory color also, and there is a trend for polychromaticity to do so as well. Differently from other studies, we find that the object contour alone also improves memory color. Thus, enhancing the naturalness of the stimulus, in terms of either surface or shape properties, enhances the accuracy and precision of memory color. The results support the hypothesis that memory color representations are polychromatic and are synergistically linked with diagnostic shape representations.

Accuracy and speed of material categorization in real-world images

“…In subsequent fMRI studies with neurologically normal participants, Goodale (2007, 2011) have shown that 3-D shape properties, which determine object identity, are processed in a different brain region from material properties. Behavioral reports support these findings (Cant, Large, McCall, & Goodale, 2008), although there is clear evidence of an interaction: Material properties influence the perception of 3-D shape (Fleming et al, 2004;Ho et al, 2008;Fleming, Holtmann-Rice, & Buelthoff, 2011;Wijntjes, Doerschner, Kucukoglu, & Pont, 2012) and vice versa (Bloj et al, 1999;Boyaci et al, 2003;VanGorp et al, 2007;Ho et al, 2008;Olkonnen & Brainard, 2011;Vurro et al, 2013).…”

Cross-cultural variation of memory colors of familiar objects

“…Smet, Ryckaert, Pointer, Deconinck and Hanselaer [4], while investigating color appearance tolerances for familiar objects, reported similar increases in saturation for memory colors and shifts towards the dominant hue for most familiar objects. Vurro, Ling and Hurlbert [5] also found hue shifts in memory colors of natural objects, but these were not systematically towards the dominant hue of the object. They also found that hue shifts were reduced by increasing the naturalness of the stimuli.…”

Bias effects of short- and long-term color memory for unique objects

“…In a more recent and sophisticated study [12] that incorporates the polychromaticity of natural objects participants adjusted only the mean hue of 3-dimensional objects that represented fruits and vegetables to settings that were "redder" and "bluer" than the measured values of the unseen exemplars. A common element between this study and other recent ones [e.g.…”

“…They indicate that variations in Chroma and Hue for blue and yellow colors were larger than those for red and green ones and not in the same direction. They also report finding larger shifts for the condition with complex background.In a more recent and sophisticated study [12] that incorporates the polychromaticity of natural objects participants adjusted only the mean hue of 3-dimensional objects that represented fruits and vegetables to settings that were "redder" and "bluer" than the measured values of the unseen exemplars. A common element between this study and other recent ones [e.g.…”