You might be seeing dots in front of your eyes today. Chances are your friends on social media are sharing an optical illusion that challenges you to see 12 dots on one image, all at the same time. Good luck with that. What you're seeing is a take on the classic Hermann-grid illusion that makes dark spots appear in the crosshatches of a black-and-white grid.
The 12-dots version of the illusion traces back to scientist and visual-illusions specialist Jacques Ninio, author of a paper on Hermann grid variations published in 2000 in the journal Perception. If the black-dots illusion isn't enough for you, then check out Ninio's reverse version in PDF format that has you searching for white dots against a black background. It's just as illusive.
The illusion isn't new, but the internet just recently discovered it and went bonkers over the illustration. An Imgur post of the picture has over 2.3 million views and gobs of Reddit users are commenting on the mind-boggling challenge. "It's like playing whack-a-mole with your eyes," notes Reddit user Ripsaw99, in reference to the arcade game that requires to you smack down toy moles that pop up out of holes.
You can chase the dots with your eyes, but you probably won't ever be able to see all of them simultaneously. That's both the fun and frustration of Ninio's clever illusion.