Science says the colour of the dress is...

By Young Wang

There’s some pretty complicated science behind the photo which has split the web

By Young Wang |

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The dress responsible for breaking the Internet and causing massive debates worldwide.

To find out how #TheDress managed to break the internet, we talked to a neurologist from the University of Hong Kong.

Professor Raymond Cheung Tak-fai, a clinical professor at HKU’s Department of Medicine, says his brain tells him that the dress is black and blue. But he can imagine that the lights from the top of the photo make it appear white and gold.

It all comes down to the lighting in the place you are looking at the photo, and the sensibility of your retinas.

Rods and cones are two types of photosensitive cells in our retinas, which are sensitive to lights. Rods are able to respond to a low intensity of lights, but don’t pick up colours very well. That’s why it’s normally hard to differentiate colours when it’s dark, explained Cheung. Cones on the other hand, are more sensitive to colours. Different cones respond to different light waves, that’s how our brain picks up various colours. To have a clear idea of what colour we are looking at, we need the lighting around us to be good.

“The brain is what tells us about the colours,” said Cheung. The only colours our retinas “see” are red, green and blue. What colours we can actually see depends on how much of each colour reaches our brain.

You can see white when the reflection of the colours is equal and when there’s plenty of light reflection. When light reflection is not enough to stimulate rods, the brain will “tell” you it’s black, and that’s what you see.