This optical illusion by artist Oleg Shupliak features a sketch of a woman, but there are actually four women hidden in plain sight – but good luck finding them all!

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.

Medical imaging experts are adept at solving common optical illusions, according to research from four UK universities, including the University of East Anglia. The correct analysis of medical images ...

Optical illusions are great fun, and they fool virtually everyone. But have you ever wondered if you could train yourself to unsee these illusions? Our latest research suggests that you can. Optical ...

In this Ebbinghaus illusion of relative size perception, the orange circle on the left looks bigger than the one on the right - but it is actually 10 per cent smaller. In a new study, medical imaging ...

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For the first time, research shows that a certain kind of visual illusion, neon color spreading, works on mice. The study is also the first to combine the use of two investigative techniques called ...