Variations in normal color vision III Unique hues in Indian and United States observers

Abstract

Basic color categories are thought to share a common pattern across linguistic groups, yet the focal colors defining those categories can vary substantially within any single group. We asked whether focal colors can also differ systematically across different groups of individuals living in potentially different color environments, by measuring focal and unique hues for observers in India and the United States. Differences between groups were generally small relative to the within-group variations, consistent with a strong common basis for color naming across diverse contexts. However, for most hues the average settings differed significantly across subpopulations. These differences persisted across testing conditions and thus probably reflect longer-term contextual influences on color appearance judgments. They suggest that while color categories may be qualitatively similar, precisely how the hue spectrum is parsed may differ quantitatively across different populations of observers. Both the between-group and the within-group differences are inconsistent with the differences predicted by common peripheral sources of variation in color vision (e.g., in lens or macular pigment) and may reflect an influence of environmental or cultural differences in focal color choices.

Re-locating colors in the OSA space

“…According to the author, this would support the hypothesis of a neurophysiological basis for the perceptual mechanisms guiding foci localization, that would dominate over cultural influences. These findings are in agreement with those of Webster et al (2002). In their experiment, they addressed the question whether focal colors can differ systematically across different groups of individuals living in potentially different color environments.…”

“…This would allow checking the crosscultural coherence assumption, namely if cross-linguistic differences do have any impact on color categorization. However, we assume here that between-cultural differences are comparable to within group variations (Kuehni, 2005;Webster et al, 2002).…”

Color categories: Evidence for the cultural relativity hypothesis

“…In fact, if anything, it is the Berinmo data that would dispute their hypothesis as they live in lowland dense forest that sunlight does not easily penetrate. However, in a recent investigation, Webster et al, (2002) showed systematic differences in the location of unique yellow judgments, in the absence of color-vision defects, within a population living in an equatorial region (India). These differences were attributed to cultural constraints (one population was composed of cloth factory workers who use particular shades of yellow thread) as the sunlight (UVB) exposure was equated for both groups (see also Hardy et al, in press).…”

Variations in normal color vision IV Binary hues and hue scaling

“…26 In this study we examined the structure of color appearance by observing individual differences in color naming. Subjects with normal color vision have been previously shown to vary widely in the stimuli they select for the unique hues 10,[27][28][29][30][31] and in the focal stimuli they select for basic color terms. 18,21,22,31 Thus a yellow that appears distinctly reddish to one observer might appear strongly greenish to another.…”