Richer color experience in observers with multiple photopigment opsin genes

Abstract

Traditional color vision theory posits that three types of retinal photopigments transduce light into a trivariate neural color code, thereby explaining color-matching behaviors. This principle of trichromacy is in need of reexamination in view of molecular genetics results suggesting that a substantial percentage of women possess more than three classes of retinal photopigments. At issue is the question of whether four-photopigment retinas necessarily yield trichromatic color perception. In the present paper, we review results and theory underlying the accepted photoreceptor-based model of trichromacy. A review of the psychological literature shows that gender-linked differences in color perception warrant further investigation of retinal photopigment classes and color perception relations. We use genetic analyses to examine an important position in the gene sequence, and we empirically assess and compare the color perception of individuals possessing more than three retinal photopigment genes with those possessing fewer retinal photopigment genes. Women with four-photopigment genotypes are found to perceive significantly more chromatic appearances in comparison with either male or female trichromat controls. We provide a rationale for this previously undetected finding and discuss implications for theories of color perception and gender differences in color behavior.

How to use individual differences to isolate functional organization, biology, and utility of visual functions; with illustrative proposals for stereopsis

“…Studies of natural and laboratory experiments in color vision have historically been undertaken in concert, leading to complementary insights about both the genes that encode color photopigments and the variations in them that lead to colorblindness and color anomalies (Jameson, Highnote & Wasserman, 2001;Pickford, 1951).…”

Effect of Gender, Experience, and Value on Color Perception

“…1,10,11 It is known that men and women differ in their capacity to distinguish shades, 7,12,13 and traditionally women have been considered better at selecting shades than men. 11,14 The majority of studies have attached little or no importance to the observer's gender at the time of shade selection, even though this is a variable that can influence the end result of the selection process. 8,12,13 Another variable to consider in shade matching is the observer's clinical experience, which can alter the capacity to reproduce the matching process.…”

The Causes and Consequences of Color Vision

“…Some estimates suggest four-photopigment females represent up to 50% of the female population; 8% of males are presumed to have four-photopigment retinas (Neitz et al 1998). Their study suggested that women with four-photopigment retinas perceived more chromatic bands in the typical rainbow spectrum than either men or women with trichromatic retinas (Jameson et al 2001).…”

“…Even though half of the X chromosomes in a female become inactivated, if this is random in relation to the allele on the X for LWS, heterozygous females will have patches of cones with one or the other of the LWS photopigments. Behavioral studies have found that these females can detect more colors than females or males that are trichromatic (Jameson et al 2001). The two different LWS alleles also means that trichromatic males and females will differ in their perception of red light, depending on which LWS allele is on the X chromosome.…”