title: Tyndall's paradox of hue discrimination.
abstract: We confirm a remarkable but forgotten property of human color vision that was described over 50 years ago by Tyndall [J. Opt. Soc. Am 23, 12 (1933)]: if wavelength discrimination is measured in the region of 455 nm, the sensitivity of the eye improves when a large fraction of the monochromatic light in each half of the matching field is replaced by white light that is common to the two halves. We demonstrate that a similar facilitation also occurs when the shortwave monochromatic components are held constant in luminance and a long-wave desaturant of increasing luminance is added to the shortwave discrimanda. We relate these phenomena to the properties of postreceptoral visual channels.
authors.affiliation: Department of Experimental Psychology, University of Cambridge, UK.
authors.forename: J D
authors.initials: JD
authors.lastname: Mollon
authors.forename: O
authors.initials: O
authors.lastname: Estévez
mesh_terms: D003118:Color Perception / Q000502:physiology*; D004192:Discrimination, Psychological / Q000502:physiology*; D006801:Humans; D008027:Light; D008297:Male; D008960:Models, Psychological; D011601:Psychophysics / Q000379:methods