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Carpal Tunnel
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the worthless word for the day is: achromatopsia
[fr. Greek akhromatos, without color + -opsia] /a krO muh TAHP see ah/ a visual defect marked by total color blindness, the colors of the spectrum being seen in tones of white-gray-black
"Total colorblindness caused by brain damage, so-called cerebral achromatopsia, though described more than three centuries ago, remains a rare and important condition." - Oliver Sacks, An Anthropologist on Mars
"Scdoris has congenital achromatopsia, a hereditary visual impairment that affects her ability to properly perceive depth and fine details, particularly in bright light." - Corvallis Gazette Times, OR - Jun 25, 2005
I didn't know there was such a thing as "total" colorblindness.
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"I didn't know there was such a thing as "total" colorblindness." Uh-oh--is that some kind of trick comment? Do you mean you didn't know there was such a condition, or that you never heard it described as such? Or something else altogether?
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my dad was "colorblind"; it was a red-green impairment. achromatopsia, as described, is grayscale vision.
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one of the case studies Dr Oliver Sacks profiled in his book An Anthropoligist on Mars was about a man, who as result of an neurological accident (i think it was a fall, it might have been a car crash) became achromatopiacist..
at first, it effect not only his art, but every aspect of his life.. (he began to destest garden fresh ripe red tomatoes, that were coal black globes, and repulsive and unappatizing to look at.)
i don't think achromatopsia is common condition, (or one that occures as a birth defect,) but it can occur as a result of stroke, or head injuries.
most color blindness is to specific parts of the spectrum, not to the whole spectrum of color.
like all of the cases Dr Sacks has profile over his years, this one is facinating.
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>one of the case studies Dr Oliver Sacks profiled
yes indeed; see citation above..
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"grayscale vision" Okay; thanks. This was the first type I heard of; it wasn't until some years later that I learned there can be specific colors to be 'blind' to. There was some undersea movie...The Abyss?...where somebody needed to cut either the yellow or the blue wire, as I recall--but the effect of being underwater made the two indistinguishable.
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made the two indistinguishable.
Try playing Trival Pursuit by candlelight sometime. The pink and orange are barely distinguishable and the blue and green are barely distinguishable. And who knows what color that brown is?
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re: The pink and orange are barely distinguishable and the blue and green are barely distinguishable. And who knows what color that brown is?
well there is color (take a crayon of red or blue or yellow)(primary' colors
these are pretty 'pure' colors.. then there are complementary colors (orange, purple, green) and there are colors between all these colors, (yellow orange, orange yellow, blue violet, red violet..
but there are also shades and tones (take red, add some black (shade the color) and you get red to turn into marroon.. take the same red, and lighten the the color by diluting it, or adding white, and you get a shade of pink..
if you have a range of colors (blue, yellow, green, pink, violet) that are all about the same shade or the same tone its very hard to tell them apart --(the younger you are the easier it is.
fiberbabe- will know this too-
there is a tool used by quilters (and others) that is made from dark, but pure red acetate. (its a sheet) and its used to measure contrast. color alone doesn't create contrast. you also need to have different intensities of color. when you look at a range of all pastel, or all mid tone, or all shades of colors, through the red 'filter' they can become all a shade of redish grey. (often the same shade of grey!
but a mixture of yellows, from the palest yellow to a pure yellow, to a ocher or other shade of yellow will be clearly different shades of grey.
the trivial pursuit colors all have the same tonal value.. but if they had different tones, even by candle light, you would be able to tell the colors apart.
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