Apologies for the headaches the above GIF may induce but it’s an interesting little example of not completely known human biology and currently all over the internet here in Japan. If it’s not spinning now then just click on the image to start. Once the animation gets into full swing you should be able to see some colors flickering around with those black lines.
Now, what if I told you that other people see different colors than those you do? Moreover, what if I told your there aren’t any colors at all, and it’s just your mind playing tricks on you?
Before you go shoving a pencil in your ear to punish your brain for such trickery, let’s take a moment to see what’s going on here.