This Blue or Green Spectrum Illusion Depends On How Your Brain Perceives Color


Tom Hale

Senior Journalist

clockJun 21 2016, 16:56 UTC

Optical Express

Since you have just recovered from the white-gold/black-blue dress, and then the color shifting track top, here’s another color experiment that is messing with people’s perceptions and dividing opinion.

The experiment was created by Optical Express to show off the wide variety of visual interpretations we can create from the same stimulus. 


Check out the color above. Would you say it is blue or green?

Now look at the central image, labeled 2, below. What color would you say that is?

Image credit: Optical Express


Out of 1,000 respondents, 64 percent said the first (top) image showed the color green, while 32 percent believed it to be blue. However, when the same participants were asked to label the color when it was laid next to two other noticeably blue shades, over 90 percent said it was green.

According to Optical Express, the values on the RGB (red, blue, green) color model show that the image has 0 red, 122 green, and 116 blue – meaning the color is technically green.

Although, understandably, no answer is concretely correct as we all perceive and interpret color in different ways. If your interpretation of the color is significantly different to others, however, it could hint at a form of color blindness.


It is also worth considering that language also plays a big role in this, as it could simply be we define colors differently even if we see and understand them to have the same qualities. 

Stephen Hannan, Clinical Services Director at Optical Express, explains: “Every single person is unique and as a result, our brains process information differently. Depending on how you interpret colors, one person might see it one way, while the very next person who looks at it might see it differently."

“Light enters the eye and hits the retina, which is the light-sensitive tissue at the back of the eye,” he added.


“The light is converted to an electrical signal which travels along the Optic Nerve to the Visual Cortex in the brain. The brain makes its own unique interpretation of this electrical signal.”

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