An optical illusion has gone viral because of the way it uses a clever brain trick to dilate your pupils, but it doesn't work on everyone - are you immune to it?

A new optical illusion has been leaving people confused, as staring at it for too long will make you feel as though you're getting sucked into a black hole - but it's all a trick of the mind. The illusion is comprised of several black dots that converge into a large black circle in the middle of the picture, but the more you look at the image, the more it seems that the black space in the middle is expanding to fill the whole picture.