An optical illusion challenges viewers to find a subtle anomaly within a repeating pattern of the letters HJKL. The brain's tendency to overlook details in consistent patterns makes spotting the rogue ...

Optical illusions are good at testing attention to detail. So if you are looking for a tough mental challenge to see if your brain really pays attention, then this optical illusion today will test ...

Remember the graph paper you used at school, the kind that’s covered with tiny squares? It’s the perfect illustration of what mathematicians call a “periodic tiling of space”, with shapes covering an ...

Optical illusions have long fascinated people by tricking the brain into seeing things that aren't quite right, or at least not at first glance. Today’s visual puzzle is no different. At first sight, ...