Take a look at the image above. Take as much time as you want. It looks as though there's one, maybe two dots at the intersections of the diagonal gray lines, but the dots are constantly moving, right?
The dots are **t moving: it's a static image and there is a total of 12 dots in the picture (check out the full version of the image, below).
We've seen our fair share of opticalillusions — even variations on the one above — but rarely is one so undefeatable as this. It's nearly impossible to see more than maybe three dots at once, even when you've convinced your brain there are 12 dots. * Read more...