While new optical illusions go viral all the time, here are some of the most famous illusions that have kept us scratching our heads for years.

Optical illusions are older than you think. The first optical illusions date back to 20,000 BC and took the form of cave sculptings. Nowadays they are found all over the place – on screens, in books ...

Optical illusions play tricks on your brain and can make you see things that aren't really there, from static images swirling around the page to images that stay with you even after you look away.

What colour are the dots in this image? A mind–boggling optical illusion has been developed by scientists to show how our perception of colour can be easily skewed. At first glance it may seem like a ...

The regular Short Wave science roundup covers mysterious red dots in space, the neurons behind optical illusions and a study of octopus arms. It's time now for our science news roundup from Short Wave ...

Last August Hinnerk Schulz-Hildebrandt noticed something strange while he was looking at a flight map on his phone. As his eye traced the plane’s flight path, he noticed that the line looked purple, ...

If you have never seen an optical illusion, it is an image that makes you see things differently than they actually are. Optical illusions trick your eyes into believing you see something that is not ...

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