Variation in the action spectrum of erythrolabe among deuteranopes.

Abstract

SUMMARY1. Eight deuteranopes matched a mixture of a monochromatic light on the long wave side of the neutral point and a violet (450 nm) primary to a fixed white as well as a monochromatic light on the short wave side of the neutral point mixed with a red (650 nm) primary, to the same white. For A > 530 nm, the former set of matches defined the action spectrum of the long wave sensitive foveal cones, and for A < 480 nm, the latter that of the short wave sensitive cones.2. Individual differences in the former matches were approximately correlated with the respective ratio of the sensitivities of the wave-length of the anomaloscope primaries, in a way that individual differences of the latter were not.3. Assuming that eye media differences alone account for the differences in long wave sensitive foveal action spectra, the spectral reflectivity of the foveal fundus was predicted for these deuteranopes. The prediction is inconsistent with measurement.4. Thirteen deuteranopes matched monochromatic spectral lights with a green (535 nm) and a blue (460 nm) primary. The results were analysed by von Kries' method in which differences in matching due to differences in eye media absorption are obviated. The matches of five differed significantly from one another when so analysed. It was concluded that at least one of the two action spectra of the foveal cones of every one of these five differed from that of all of the others.5. The canon that deuteranopes accept normal colour matches was evaluated by confronting a single normal with five deuteranopes in the analytical anomaloscope of Baker & Rushton, set in the mode of each of the five in turn. Obvious differences existed between this normal's matches and those of four of five deuteranopes.

L and M cone relative numerosity and red–green opponency from fovea to midperiphery in the human retina

“…68 In accordance with this finding, there is reported to be a modest difference of 4.3 nm in max of two L cone pigment absorption spectra derived with photobleaching in tissue culture cells transfected with DNA clones of human genetic material. 69 These measurements, indicating a modest range of differences in the cone pigments among individuals, are generally consistent with conclusions from psychophysical studies, yielding estimates of little 67 or modest [71][72][73][74] variability for the range of max differences in any cone class among color-normal individuals. However, results from microspectrophotometry 75,76 are consistent with a larger variability of 10-12 nm in the peak absorption of L as well as M cone photopigments.…”

The red and green cone visual pigments of deuternomalous trichromacy.

“…The apparatus is the trichromator previously described (Alpern, Bastian, Pugh & Gras, 1976;Alpern & Pugh, 1977). A disk-annulus matching field is supplied by three primaries (444.5, 550, and 650 nm) made 'monochromatic' by narrow band (10 nm half band width Baird Atomic) interference filters, two of them in light beams illuminating the annulus (30 outer diameter) the third, in one supplying the central disk (10 diameter).…”

“…Wave-length discrimination predictions from INTRODUCTION Two previous papers in this series studied foveal vision in deuteranopic dichromacy. Every one of fifteen deuteranopes lacked one foveal photolabile pigment (Alpern & Wake, 1977) and subtle individual differences were found in erythrolabe (the remaining red-green cone pigment) even in addition to any differences imposed by variability in eye media losses (Alpern & Pugh, 1977). If, as is commonly believed, deuteranopia is a reduced form of trichromatic vision then similar individual differences must appear in the long wave cone visual pigment of trichromats.…”

“…If, as is commonly believed, deuteranopia is a reduced form of trichromatic vision then similar individual differences must appear in the long wave cone visual pigment of trichromats. Alpern & Pugh (1977) found that four of five deuteranopes rejected the colour matches of one normal trichromat presumably because the erythrolabe in his long wave sensitive cones had spectral characteristics similar to those of the erythrolabe in only one of the five dichromats. It was expected that the colour matches of other normals would agree with those of other deuteranopes and recent experiments, still unpublished, show this to be true.…”

Application principles for multicolored displays. A workshop report

“…For example, Alpern and Pugh (1977) have data suggesting that differences in the maximum of the long wavelength photopigment vary over a 7 nm range. Molion (1982) has summarized a number of studies that suggest this possibility and reviewed possible sources of error.…”