Almost two years ago to this day, the world went into a tailspin over a picture of a dress.
On February 26th 2015, a woman uploaded a picture of a dress she intended to wear at a wedding in Scotland.
The problem was, people were seeing the colours of the dress differently. Some saw it as white and gold, and others as blue and black. Arguments were had. Friendships were destroyed. Celebrities weighed in. Even Tay Tay took a stance on the topic. In a short time, The Dress became a fully fledged meme.
I don't understand this odd dress debate and I feel like it's a trick somehow.
I'm confused and scared.
PS it's OBVIOUSLY BLUE AND BLACK
— Taylor Swift (@taylorswift13) February 27, 2015
Eventually, scientists intervened and resolved the dispute. For the record, The Dress was actually blue and black, but the way you saw it depended on how your brain perceived the light in the room the photo was taken in. It’s related to the concept of “colour constancy” and it’s a feature of human colour perception that attempts to make sense of colours under varying lights.
So when you look at The Dress your brain either assumes a white light or a bluish shadow. If you perceive a white light, The Dress appears blue and black and if you perceives blue light or a shadow, The Dress appears white and gold.
A day after the two-year anniversary of The Dress, people once again started going bonkers over a picture of some strawberries.
Strawberries appear to be reddish, though the pixels are not. pic.twitter.com/Ginyhf61F7
— Akiyoshi Kitaoka (@AkiyoshiKitaoka) February 28, 2017
The picture was created by Akiyoshi Kitaoka, a professor of psychology and optical illusion artist at Ritsumeikan University in Japan.
Matt Lieberman, a neuroscientist at the University of California then followed up with another version:
This picture has NO red pixels. Great demo of color constancy (ht Akiyoshi Kitaoka) pic.twitter.com/pZHvbB6QHE
— Matt Lieberman (@social_brains) February 27, 2017
The reason we see these strawberries as red is also related to colour constancy.
In the original picture, Kitaoka created a light source that your brain interprets as having a bluish component. Your brain then compensates by subtracting the blue bias from the grey pixels, giving the image the red tint that you see.
With The Dress, people saw different colours because of how they differently imagined light. However, in this example, everyone sees the strawberries as red. Why? It’s also partly because we know strawberries are red.
— Carson Mell (@carsonmell) February 28, 2017
This raises an interesting question: What if you showed this picture to someone who had never seen a strawberry? What colour would they see?
They would see grey.
David Atchison, a professor in the School of Optometry and Vision Science at the Queensland University of Technology, confirmed this. He told CNET: “If you didn’t know that strawberries are supposed to be red, they would indeed look grey.”
If you need proof, Atchison suggests you try this simple experiment at home: Grab a piece of paper and punch a tiny hole in it. Now place the paper on top of your computer screen, so that you can isolate a tiny piece of a strawberry. What do you see?
I just did it, and yup, the strawberries aren’t red. Stupid brain.