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.

This mind-bending optical illusion by Ukrainian artist Oleg Shupliak has stumped 98% of viewers - can you find all four women cleverly hidden in the image of a woman on her phone?

Seeing feels immediate; we open our eyes and the world seems to appear as a continuous stream. But some visual illusions show ...

Illusions like these mess with the brain's visual processing system, making viewers see things that aren't there in reality. | Credit: Eva Almqvist via Getty Images Optical illusions play tricks on ...

Visual illusions are designed to fool our brains and eyes. These illusions tend to explore the limitations of our visual system. Illusions occur when our brain fills in missing information to process ...

A collection of three 3D printed optical illusions featuring clever geometry, unique perspectives, and visual tricks that ...

Susana Martinez-Conde is director of the Laboratory of Visual Neuroscience at the Barrow Neurological Institute in Phoenix, Arizona. She studies visual illusions to gain a better understanding of how ...

Medical imaging experts are adept at solving common optical illusions, according to research from four UK universities, including the University of East Anglia. The correct analysis of medical images ...

They say human attention spans are down to three seconds. I set out to prove that wrong.Watching paint flow across a canvas ...