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.

Viewers are frazzling their brains over this seemingly innocent photograph of a gracefully stretching ballerina — which hides a highly sinister image. [Warning: Spoilers below] The illusion has ...

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These mental litmus tests will melt your mind. Puzzle lovers are straining their brains trying to solve a trio of baffling optical illusions, which reportedly reveal how the viewer’s mind works. A ...

Optical illusions are interesting images that challenge our minds, inviting us to solve a puzzle and find what is hidden.And ...

How optical illusions work has been long-debated among scientists and philosophers, who wonder whether these illusions stem from neural processing in the eye or involve higher-level cognitive ...

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 ...