Luminance-dependent long-term chromatic adaptation

Abstract

There is theoretical and empirical support for long-term adaptation of human vision to chromatic regularities in the environment. The current study investigates whether relationships of luminance and chromaticity in the natural environment could drive chromatic adaptation independently and differently for bright and dark colors. This is motivated by psychophysical evidence of systematic difference shifts in red-green chromatic sensitivities between contextually bright- versus dark-colored stimuli. For some broad classes of scene content, consistent shifts in chromaticity are found between high and low light levels within images. Especially in those images in which sky and terrain are juxtaposed, this shift has direction and magnitude consistent with the observed psychophysical shifts in the red-green balance between bright and dark colors. Taken together, these findings suggest that relative weighting of M- and L-cone signals could be adapted, in a luminance-dependent fashion, to regularities in the natural environment.

Variations in normal color vision. VII. Relationships between color naming and hue scaling

“…It remains to be examined whether other attributes of color vary in similar ways. For example, conventional color models treat lightness and hue as largely separable dimensions, but it is well known that yellow exists only as a lighter color while decrements instead appear brown, and recent results suggest that the nulls for unique yellow and brown are different (Buck, 2015, Vincent, Kale & Buck, 2016). However, it is not known whether individual differences in the hues of increments and decrements vary independently, nor how color naming or scaling might differ between observers as a function of saturation.…”

Color Compensatory Mechanism of Chromatic Adaptation at the Cortical Level

“…However, the aftereffects of photoreceptor adaptation are known to be highly ephemeral, typically lasting only a few seconds ( Rinner & Gegenfurtner, 2000 ), and the duration of these experiments could be too long for photoreceptor adaptation, which is known to exhibit temporal characteristics different from those of the central components of adaptation to chromatic light ( Shimakura & Sakata, 2019 ). This suggests that even if there was a slight effect of the adaptive light on the foveal photoreceptor cells, the results were due to the effects of a long-term adaptation mechanism, which is reported to have different temporal characteristics ( Vincent et al, 2016 ; Belmore & Shevell, 2008 , 2011 ). The duration of the chromatic compensation observed in our experiments could not be explained only by the photoreceptor contribution.…”