Today’s optical illusion is challenging viewers to find a hidden "5" among a sea of "2s." The tricky pattern plays with human perception, making it hard to spot the odd number. Can you find it?

Our brain and eyes can play tricks on us—not least when it comes to the expanding hole illusion. A new computational model ...

Bridget Riley’s inclusion in The Responsive Eye at MoMA, HH-H’s exhibition features early Riley b&w paintings and drawings ...