Color processing in the primates Essay -- Biology, Visual System, Colo

Color is a feature that is possessed by very few mammals. K .Tansely in one of his books on visual system the vision in vertebrates commented that â€Å"On the whole mammals appear not to have color vision, except for the primates where it is well developed and almost certainly trichomatic†. The word trichomatic was derived from a theory given by French physiologist Palmer in 1777 which stated the presence three different types of infinite number of molecules present in the human retina. These types are for detection of colors like red, blue and yellow. Few years later Thomas Young postulated the presence of three types of cones which are responsible for the detection of these primary colors or metamers and their concept of empirically proven by Maxwell in 1860. This trichomatic nature of perception of human retina seemed a limitation as human eye can perceive millions of colors. These millions of colors are limited to a Grassman’s laws explained additive, scalar and associative properties of metamers to prove the different combinations of colors perceived by visual system. The human range of perception of light is from 380nm to 760nm. The perception of color depends upon photo-receptors ability to segregate different wavelength. The Bowmaker et al in 1979 was able to identify the cone using micro-spectrometry by seeing cone absorption spectrum.The cones were in blue, green and red spectrum with wavelength of 420nm, 534 nm and 564 nm. The rod that was identified absorbed the spectrum at 498 nm. The results on the absorption spectrum were quite similar to the results found on Rhesus monkey by the same author. *Bowmaker et al. The name given to cones on the absorption spectrum are S(Short), L(Long) and (M) moderate . T... ...gnocellular pathway cells is shown by grey cells.(Martin 2004) The third and the smallest layer is Koniocellular that is present between the Parvocellular and magnocellular consist mainly of inter-neurons. The blue-ON cells form a connection with small bistratified ganglion cells and it ends in Koniocellular cells. These small size neurons project into supragranular layer 2, 3 and upper part 4 including the cytochrome oxidase rich ‘blob’ region of visual cortex. *Sampling density of blue-ON cells relative to the S-cone array is shown by white circles.(*Martin 2004) There is unknown pathway that begins from wide receptive field yellow-ON ganglion cells and ends at unknown destination in Lateral Geniculate Nucleus. *The small white circle at position of S-cone represents the postulated midget blue-OFF cells ganglion cells. (Martin 2004) Color processing in the primates Essay -- Biology, Visual System, Colo Color is a feature that is possessed by very few mammals. K .Tansely in one of his books on visual system the vision in vertebrates commented that â€Å"On the whole mammals appear not to have color vision, except for the primates where it is well developed and almost certainly trichomatic†. The word trichomatic was derived from a theory given by French physiologist Palmer in 1777 which stated the presence three different types of infinite number of molecules present in the human retina. These types are for detection of colors like red, blue and yellow. Few years later Thomas Young postulated the presence of three types of cones which are responsible for the detection of these primary colors or metamers and their concept of empirically proven by Maxwell in 1860. This trichomatic nature of perception of human retina seemed a limitation as human eye can perceive millions of colors. These millions of colors are limited to a Grassman’s laws explained additive, scalar and associative properties of metamers to prove the different combinations of colors perceived by visual system. The human range of perception of light is from 380nm to 760nm. The perception of color depends upon photo-receptors ability to segregate different wavelength. The Bowmaker et al in 1979 was able to identify the cone using micro-spectrometry by seeing cone absorption spectrum.The cones were in blue, green and red spectrum with wavelength of 420nm, 534 nm and 564 nm. The rod that was identified absorbed the spectrum at 498 nm. The results on the absorption spectrum were quite similar to the results found on Rhesus monkey by the same author. *Bowmaker et al. The name given to cones on the absorption spectrum are S(Short), L(Long) and (M) moderate . T... ...gnocellular pathway cells is shown by grey cells.(Martin 2004) The third and the smallest layer is Koniocellular that is present between the Parvocellular and magnocellular consist mainly of inter-neurons. The blue-ON cells form a connection with small bistratified ganglion cells and it ends in Koniocellular cells. These small size neurons project into supragranular layer 2, 3 and upper part 4 including the cytochrome oxidase rich ‘blob’ region of visual cortex. *Sampling density of blue-ON cells relative to the S-cone array is shown by white circles.(*Martin 2004) There is unknown pathway that begins from wide receptive field yellow-ON ganglion cells and ends at unknown destination in Lateral Geniculate Nucleus. *The small white circle at position of S-cone represents the postulated midget blue-OFF cells ganglion cells. (Martin 2004)