Left inferior parietal lobe fusiform gyrus damage causes scene to have no color and be light and dark gray {achromatopsia} [Hess et al., 1990] [Nordby, 1990].
Cone pigments can differ in frequency range or maximum-sensitivity wavelength {anomalous trichromacy}. Moderately colorblind people can have three photopigments, but two are same type: two different long-wavelength cones {deuteranomalous trichromacy}, which is more common, or two different middle-wavelength cones {protanomalous trichromacy} [Asenjo et al., 1994] [Jameson et al., 2001] [Jordan and Mollon, 1993] [Nathans, 1999].
8% of men cannot distinguish between red and green {color blindness} {colorblind} {red-green colorblindness}, but can see blue. They also cannot see colors that are light or have low saturation. Dichromats have only two cone types. Cone monochromats can lack two cone types and cannot distinguish colors well. Rod monochromats can have no cones, have complete color blindness, see only grays, and have low daylight acuity.
People can have all three cones but have one photopigment that differs from normal {color-anomalous}, so two photopigments are similar to each other. They typically have similar medium-wavelength cones and long-wavelength cones and cannot distinguish reds, oranges, yellows, and greens.
People can lack medium-wavelength cones, but have long-wavelength cones and short-wavelength cones {deuteranope}, and cannot distinguish greens, yellows, oranges, and reds.
People can lack long-wavelength cones, but have medium-wavelength cones and short-wavelength cones {protanope}, and cannot distinguish reds, oranges, yellows, and greens.
People can lack short-wavelength cones, but have medium-wavelength cones and long-wavelength cones {tritanope}, and cannot distinguish blue-greens, blues, and violets.
1-Consciousness-Sense-Vision-Problems
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Date Modified: 2022.0225