Latest Research on Colour Vision: Dec – 2019

Colour vision of domestic chicks

The colour vision of domestic chicks (Gallus gallus) was investigated by coaching them to little food containers embellished with tilings of gray and colored rectangles. Chicks learn to recognise the color quickly and accurately. Chicks have four kinds of single-cone photoreceptor sensitive to ultraviolet, short-, medium- or long-wavelength light-weight. to ascertain however these receptors square measure used for color vision, stimuli were designed to be distinguished solely by specific mixtures of receptors. we tend to infer (1) that every one four single cones square measure used, and (2) that their outputs square measure encoded by a minimum of 3 opponency mechanisms: one scrutiny the outputs of ultraviolet- and short-wavelength-sensitive receptors, one scrutiny the outputs of medium- and long-wavelength receptors and a 3rd scrutiny of the outputs of short- and long- and/or medium-wavelength receptors. Thus, the chicks have tetrachromatic color vision. [1]

Colour vision as an adaptation to frugivory in primates

Most mammals possess 2 categories of cone, sensitive to short and to long wavelengths of sunshine, however recent World primates (Catarrhini) have distinct medium and long wavelength sensitive categories. The sensitivities of those cones photopigments square measure alike altogether catarrhines with peaks at concerning 440 nm (‘blue’), 533 nm (‘green’) and 565 nm (‘red’). One doable reason for the evolution and conservativism of catarrhine visual sense is that color vision could be a specialization for locating food. A model of retinal committal to writing of natural spectra, supported discrimination thresholds, is employed to look at the quality of dichromatic and trichrome vision for locating fruit, and for distinctive fruit and leaves by color. For identification tasks the dichromat’s eye is nearly nearly as good as a trichromat’s, however the trichromat has a plus for sleuthing fruit against a background of leaves. [2]

Animal colour vision – behavioural tests and physiological concepts

Over a century past employees like J. metropolis and K. von Frisch developed behavioral criteria for establishing that non-human animals see color. several animals in most phyla have since then been shown to possess color vision. color is employed for specific behaviours, like phototaxis and visual perception, whereas alternative behaviours like motion detection ar color blind. Having established the existence of color vision, analysis focussed on the question of what number spectral forms of photoreceptors ar concerned. Recently, knowledge on photoreceptor spectral sensitivities are combined with behavioral experiments and physiological models to check consistently succeeding logical question: ‘what neural interactions underlie color vision?’ This review offers an outline of the strategies wont to study animal color vision, and discusses however quantitative modelling will counsel however photoreceptor signals ar combined and compared to permit for the discrimination of biologically relevant stimuli. [3]

Colour vision deficiency

Colour vision deficiency is one among the most typical disorders of vision and might be divided into inherent and purchased forms. inherent color vision deficiency affects as several as 8 May 1945 of males and zero.5% of females—the distinction in prevalence reflects the very fact that the most typical kinds of inherent color vision deficiency square measure transmissible in AN sex chromosome recessive manner. till comparatively recently, our understanding of the pathophysiological basis of color vision deficiency mostly invigorated on behavioral data; but, trendy molecular genetic techniques have helped to elucidate its mechanisms. [4]

Effect of Colour Vision on Ocular Deviation

Purpose: The aim of this study is to correlate the result of color vision within the presence of ocular deviation.

Methods: A pilot, cross-sectional, empiric study was performed at tertiary eye care centers. Subjects with associate Ocular deviation between ten to forty prism diopters, Corrected distance sight ought to be larger than 6/18 and Age ought to be between ten to forty years archaic were enclosed within the study. color vision was assessed with Fransworth Munsell D fifteen color vision check. [5]

Reference

[1] Osorio, D., Vorobyev, M. and Jones, C.D., 1999. Colour vision of domestic chicks. Journal of Experimental Biology, 202(21), (Web Link)

[2] Osorio, D. and Vorobyev, M., 1996. Colour vision as an adaptation to frugivory in primates. Proceedings of the Royal Society of London. Series B: Biological Sciences, 263(1370), (Web Link)

[3] Kelber, A., Vorobyev, M. and Osorio, D., 2003. Animal colour vision–behavioural tests and physiological concepts. Biological Reviews, 78(1), (Web Link)

[4] Colour vision deficiency
M P Simunovic
Eye volume 24, pages747–755(2010) (Web Link)

[5] Haradhan Chowdhury, P. and Haren Shah, B. (2018) “Effect of Colour Vision on Ocular Deviation”, Ophthalmology Research: An International Journal, 9(1), (Web Link)

Leave a Reply

Your email address will not be published. Required fields are marked *