Monochromat Capability
According to Jay Neitz, a renowned color vision researcher at the Medical College of Wisconsin, each of the three standard color-detecting cones in the retina of trichromats — blue, green and red — can pick up about 100 different gradations of color. But the brain can combine those variations exponentially, multiplying each new variety of cone by 100, so that the average human can distinguish about one million different hues. Therefore, a monochromat would be able to distinguish about 100 colors.
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