The relative luminance of a color at the threshold between gray content and apparent fluorescence (fluorence) is not much affected by the luminance of the surround but is greatly affected by its chromaticity. The results indicate that the continuum of color perceptions of a color stimulus seen against a variety of backgrounds is four dimensional. A new concept, “specific hue brilliance,” is shown to describe both the relationship of gray content to the purity of a color of a given dominant wavelength and the appearance of high-purity colors at constant luminance.
RALPH M. EVANS and BONNIE K. SWENHOLT, "Chromatic Strength of Colors, III. Chromatic Surrounds and Discussion," J. Opt. Soc. Am. 59, 628-632 (1969)