Why Your Brain Won't Let You Look at These Black Dots All at Once

A new optical illusion is here to break the internet, or at least our minds. The latest visual trick making the rounds is an image of intersecting grey lines against a white background, with 12 black dots on the nodes where the grey lines meet.

All 12 dots are really on the image, but most people are unable to see them all at the same time, making the dots seem like they appear and disappear with every blink. This occurs because the eye’s stimulated light receptors can sometimes influence the ones next to them, creating illusions.

In this particular image, tweeted by game developer Will Kerslake on Sunday, the brain can see some black dots but guesses when it fills in the peripheral vision. Because mostly grey lines appear in the periphery, the black dots don’t appear.

The image is a variation on the Hermann grid illusion, a diagram of black squares separated by white lines. Dark patches appear where the white lines intersect, but only in a person’s periphery.

How many dots can you see at once?

Write to Mahita Gajanan at mahita.gajanan@time.com.