Incredible optical illusion is NOT what it seems – can you work out what’s going on?

THIS incredible optical illusion will trick your brain into seeing colour – but it’s not what it initially seems.

The mind boggling image, initially shared by London-based digital artist Stuart Humphryes, fools your brain into seeing colour even though there is none there.

The pic demonstrates what’s called the “colour assimilation grid illusion,” and here we explain why.  

In the shot, the teenagers’ T-shirts appear green, blue, yellow or red, and the tree behind them appears green.

However, on closer inspection, you can see that the picture is actually greyscale without any colours on the garments or surrounding nature.

This is because the artist simply added a grid featuring colourful lines over the black and white image.

Stuart later explained how our brains “fill in the gap” of colour perception, and apply the grid colour to the whole of the image.

He said: “This is fascinating and shows how weak colour information can be on a photo for the brain to fill in the gaps and ‘colourise’ it for you.

“It’s a black and white photo, but overlaid with a thin grid of coloured lines. They’re enough to trick your mind into seeing a full colour image.”

The image recently remerged online on Twitter via art lover Daniel Holland who quipped that the illusion had “done his head in.”

Baffled users in the comments were in full agreement – with one labelling it “extraordinary.”

Another added: “That’s awesome and weird.”

Vision scientist Bart Anderson from the University of Sydney previously explained the phenomenon to Science Alert in 2019.

He said: “The colour system is what vision scientists refer to as ‘low pass’, i.e., many of the receptive fields that code colour are quite large.”

“So the grids get ‘averaged’ with the achromatic background, which then gets attributed to that part of the image.”

Previously, people were dumb struck by a visual trick which turned a black-and-white photograph into a full-colour rendering of a cheerful campus scene.

While others online users were going crazy for a clever optical illusion — but can you spot who is wearing the heels?