The Troxler Effect Illusion

Check out this optical illusion. It will take a minute, but it will be worth it. Before we start, let’s be clear that this is a circle of gray dots on a red field. The dots change color so that it appears a white dot and a light gray dot are racing around the circle.  

Follow the light grey spot around the circle for 30 seconds to 1 minute, and you will notice the other spot will eventually turn green.

If you stare at the cross in the middle for 30 seconds to 1 minute, the spots around the circle will disappear.

I took the time to do this, and it works! The dots turned teal green, but had varying intensities. In the second illusion, most of the dots disappeared for a bit, but never did they all disappear. I just can’t hold my eyes still enough. This illusion is an example of Troxler’s fading. There’s another, similar illusion at the Wikipedia link. I haven’t yet figured out why there is a white dot in this illusion. Read more about this effect and see three other illusions at Lensflare.  -via Boing Boing