Huh. I only see a green dot, rotating around a bunch of pink dots. Well, not
around ... taking the place of one pink dot, then the next, then the next ... you get the idea.
No matter how hard on concntrate on the + or try to follow the rotation, that's all I see.
... I think my brain must be broken.
My favorite optical illusion, so to speak, is attached here. Square A and Square B are two different shades of gray, right? Think again - they're actually the same shade. Don't believe me? Copy the image into your favorite paint program and see for yourself!