Why do people see different colors

That's why we see so different colors in this dress

An inconspicuous photo occupies millions of people online. The question of whether the colors of the dress shown are blue / black or gold / white divides the Internet into two camps. How can it be that the colors on this picture are perceived so differently?

Blue / black or gold / white? The fact that the colors are perceived so differently amazes and polarizes the network community. Representatives from both sides are convinced of their views. Our eyes can hardly deceive us so much?

When light falls on our retina, its electromagnetic waves are picked up by photoreceptors and converted into nerve impulses. The brain sorts the excess information and uses the wavelength to determine the color. Humans can distinguish 150 color tones from the spectrum of visible light.

Optical illusion

The image in question is, however, in a borderline area of ​​perception. Because people are heavily dependent on the lighting conditions when they see. The picture of the dress was taken in very bright, possibly bluish ambient light. The background can lead the brain to process the colors of the dress differently. Processes in the brain then either pull off blue light and the dress appears white and gold - or it pulls off the warm light and the dress turns blue and black.

Another theory suggests that the influence of the brain on color perception means that experiences and expectations play an important role. So, similar items of clothing seen before might guide the impression.

Prof. Dr. Nikolai Axmacher from the Institute for Cognitive Neuroscience at the University of Bochum is also astonished by the phenomenon, but admits: "There is a great variability in the retinal images. The light and the material of the dress probably play a role in the perception of this image." He mentions another example: "In sunlight, a car sometimes appears shimmering gold. Gold is created through strong reflection."

He considers the photo with the dress to be an optical illusion. We know similar images where the same gray level can be seen very differently. However, if such illusions are not planned under controlled conditions, they are even more astonishing, as in the case of the dress with its different colors.

In the meantime, the riddle about the dress has been resolved: A photo that was taken under different lighting conditions shows that it is actually black and blue. According to the description in the online shop, it is a "Royal-Blue Lace Detail Bodycon Dress". (say)

Prof. Dr. Nikolai Axmacher is head of the neuropsychology department at the Ruhr University Bochum, one of his main research areas is neuropsychoanalysis.