While optical illusions often have a mind-bending effect on me, I've never given much thought to how they affect our furry friends – but of course, someone on the internet has. Testing their feline ...

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 ...

Optical illusions are cool because they hurt your brain but in a fun way. Unlike when my older brother used me to practice his Tombstone Piledriver after watching the WWE Survivor Series — that hurts ...

Everyone loves an optical illusion — even if they leave us completely stumped — and they're all around us in the natural world. From an underwater waterfall in the Indian Ocean to a surrealist scene ...