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Looking for the I Function among the opthalmic Processes Contemplating its Character and PossibilitiesOliver Sacks wrote a case study about a 67 year old painter who lost his glossary vision as a result of a car accident. His vision was such that everything appeared to him as a black and white TV screen. After numerous tests his doctors could start out nothing wrong with his eyes and concluded that he had a obsolete cerebral dysfunction form of achromatopsia caused by visual cortex damage. Mr. I, as Oliver Sacks called him, retained an awareness of where tinge should be. His coloring perception was replaced with a nippy acuity for tones of grey to a degree not known to color-sighted hoi polloi or congenital color-blind people. He felt uncomfort adequate to(p) because he saw only awful and disgusting shades of grey where the color should have been. As an artist, his response to the loss of a fundamental readiness was to shun social and sexual intercourse, because everyone, in cluding himself, looked like animated grey statues. fare became disgusting because a black tomato suggested death to him. His awareness of where the color should be because of all the grey shades and tones was so distracting that he began to look for to surround himself with black and white-white rice, black coffee, ... even redecorating parts of his house in black and white (1).Recent research into visual perception has revealed that color recognition requires a minimum of three sub-systems to be functioning sensible receptors (the retina cones), wavelength-sensitive cells (apparently located in an area of the brain known as V1), and a high order color generating mechanism (located in the V4 region). These three processes conduct to work in harmony to yield the perception of color (1).Tests revealed that for Mr. I, the higher order color generating mechanism in V4 was not working. His other both processes were operating perfectly. Because of his two normal vision processes, M r. I was able to mark variations in grey by the comparative wavelength of the reflected light without being able to see the actual color. Mr. I could also see textures and patterns that are normally obscured to those of us because of their embedding in color. Oliver Sacks puts it this wayHis brain damage had made him clandestine to, indeed trapped him within, a strange in- between state-the uncanny population of V1-a world of anomalous and, so to speak, prechromatic sensation, which could not be categorized as either color or colorless (1).