WHAT you see in this X-rated optical illusion could mean you have a filthy mind.
A seemingly harmless picture of a group of friends appears more sinister than intended.
The picture appeared in a series of questionable photos posted to Ranker.
Two women appear in the centre of the image and are seen smiling to the camera.
But one is slightly positioned behind the other’s bare arm – and at first glance, the arm appears to be connected to the second woman’s head.
Because the first woman is wearing a sleeveless dress, the shadowing on her arm almost appears to be a body.
The puzzling picture went viral on Reddit, as users struggle to un-see the image.
The illusion, which was originally shared on Instagram by user @Singcha, shows a scene in the park.
Viewers can quickly spot a couple holding hands and a woman laying down in the grass.
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However, our eyes are instantly drawn to the woman on the grass, because she appears practically nude from the waist down.
In June 2020, researchers at the Massachusetts Institute of Technology investigated the mechanism behind the illusions.
They showed that the phenomenon relies on a quirk in the way that our brains process what we see.
When we look at an image, we estimate the brightness of an object before visual information reaches the brain’s visual cortex.
It means that objects of the same colour can appear brighter or darker than they are based on the background they’re presented on.
“All of our experiments point to the conclusion that this is a low-level phenomenon,” MIT’s Professor Pawan Sinha said at the time.