There are "forbidden colors", for example, red-green and yellow-blue

"Forbidden colors" - are the colors that a person can not see, because they consist of two shades that offset each other in human eyes. We can not only see them, but even to imagine. Red-green color - the color with shades of red and green; yellow-blue - yellow and blue at the same time.

The retina of the human eye has a special neurons called "opponents of neurons", which light up when we see red, and the flurry of activity tells the brain that we see is red. The same neurons are suppressed opponents in green. Similarly, yellow activates their activities, and blue suppresses. While most flowers is a mixture of effects among both groups of neurons that our brain can decode, red cancels green, yellow and blue cancels, so we will never be able to see both colors at the same time, coming from the same source.

However, studies show that the banned colors still possible to see. Researchers have created images in which red and green and the other blue and yellow stripes "ran" for each other. They showed pictures of tens of volunteers, using an eye tracker, which clearly recorded at the level of the human eye. This ensured that the light from each color band worked on the same cells of the retina, for example, some cells have always perceived only yellow color, while the other only the blue.

As a result, participants in this visual experiment reported that they had seen gradually disappearing borders between colors and two colors were transformed into one. Surprisingly, the experts managed to redirect the work of the cells of the retina, and the people saw the color, with which they had never before encountered.

The authors wrote in their paper that each of the participants, calling them a visible color "both red and green." In addition, a number of respondents, despite the fact that they knew what color look, they could not be called a word that see or even describe the color. At the same time, one of the participants was an artist with a large "color dictionary».

via factroom.ru