It's similar to this image: https://i.imgur.com/Zihujue.jpg https://i.imgur.com/Zihujue.jpg Try staring at that for a few seconds. The best explanation is that

It's similar to this image: https://i.imgur.com/Zihujue.jpg https://i.imgur.com/Zihujue.jpg Try staring at that for a few seconds. The best explanation is that it overloads the edge detectors in your brain. There are some other possible explanations here: https://www.reddit.com/r/explainlikeimfive/comments/1sgn7v/eli5_why_does_looking_at_this_picture_hurt_my_eyes/ https://www.reddit.com/r/explainlikeimfive/comments/1sgn7v/e...