This brain-frazzling optical illusion is enough to put your head into a spin. The purple-and-yellow image looks as though it’s both three-dimensional and moving but is in fact stationary and flat.

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 ...

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Think you can trust your eyes? Think again. What feels undeniable at first glance is sometimes a surprise, an illusion, or an ...

This video stacks multiple visual illusions that don’t make sense at first glance. However, once each trick is explained, the ...

You have to see it to believe it, they say. But can we really trust our eyes? The answer is not quite. It was found that our eyes can trick our brains into believing things that aren’t there and vice ...

Our visual system is constantly making assumptions about what we see. In one of my first psychology courses in college, our professor used an effect from Disney's classic Haunted Mansion attraction to ...

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