I love optical illusions. First of all, they are cool, secondly the good ones teach us something about the way our eyes and brains work. One of the neat things about the internet is that it makes it really easy to share animated optical illusions. Check this one out:
If you follow the pink dos with your eyes, then nothing too exciting.
If you focus on the black + in the middle, you will probably see a green dot that replaces the pink dot that disappears. This is a negative afterimage effect (neon green being the compliment to pink). I’ve seen similar illusions before.
Then the really cool effect is if you focus on the black + long enough, all the pink dots will disapear, and you will just see the green dot spinning around the circle. If you move your eyes, then the pink dots will come back though.
Your eyes will see all this from the same animation. The animation doesn’t change. You might ask yourself what else gets distorted in your life when you are focused on one thing? Do other things tend to disappear? When is that a good thing? When is it not?