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.

One is dark, one is light. One is gray, one is white. These are obviously two different blocks with two different colors right? Wrong. The two blocks are the same color. Seriously, they’re the same ...

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In the classic “rubber hand” illusion, a participant is tricked into experiencing a fake arm on the table in front of them as their own: their brain “feels” the tickle of a feather or other stimuli ...

A viral optical illusion image that has recently been making rounds on the internet has left people confused. At first glance, the image looks like an angry man. But when the picture is turned upside ...

If you can’t spot it in the image up top, try clicking through for the hi-res. You’ll know it when you see it. Redditor adepssimius (that would be Ben) says he had to wait until the notices had been ...