A bizarre trick of the eye creating the illusion of an impossibly tiny waist on a Paris Olympics swimmer went viral, the second moment of the games that made viewers at home do a double-take. A video ...

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.

The optical illusion inside butterfly wings is similar to the barber-pole illusion. When looking at the red-and-white striped ...

Optical illusions often go viral, but they've been around long before social media. Here are 10 historical illusions that ...

A bird attacking a butterfly will often find its beak snapping at thin air. According to new research, that split-second miss ...

Optical illusions are older than you think. The first optical illusions date back to 20,000 BC and were seen in caves. Nowadays they are found all over the place – on screens, in books and even in ...

Researchers shot butterflies taking off in super slo-mo and found the patterned wings may actually be an optical illusion to make predators miss ...

It’s like putting on ugly goggles. Puzzle lovers are getting the heebie-jeebies over this “freaky optical illusion,” which makes people’s faces look hideously distorted. A now-viral video detailing ...

Scientists say buterfles' flapping patterned wings create motion illusion effects that "scramble" predators' aim.

The Illusion Divide: When exposed to a motion aftereffect, human observers perceive a stationary object as shifted in the opposite direction. Primate inferior temporal (IT) cortex neurons mirrored ...