The Dress, The Eye and Color Blindness
The eyes are a fascinatingly unique organ whose complexities require years of specialization to understand. Recently there was a highly publicized argument on the internet on the color of a dress. Many saw the dress as blue and black, others as white and gold. It gave everyone the opportunity to learn things about the eye that are normally reserved for those that study it.
First, it’s important to understand that the eye does not see, the brain does. The lens of the eye focuses light entering the eye onto the retina. The retina then sends this information through neural pathways to the visual cortex in the brain.
When the visual cortex is trying to ascertain the color of certain objects it is essentially making important calculations. The brain takes into account the amount of light and, in this case, the background of the photo to make these calculations.
Though it may cause some online arguments periodically, this is a highly important feature of the eye. Humans can see best during the day, but the color at 7am is different from the color at 7pm, and in relative darkness you can still discern colors of various items.
Color blind people who weighed in on the dress reported seeing a dark color and a pinkish color, which they often see instead of the color blue. Most of the color blind people also reported being happy that normal-sight people got to experience being color blindness for a short period of time.
Color blindness occurs more often in men and is a result of a lack of pigment in the cone cells of the retina that is color sensitive.
For those that remain curious, the dress is actually blue. Those that were adamant about it being white and gold were likely making calculations with a lighter background.