Fraser Spiral

photo courtesy of www.illusionworks.com

 

The image above, commonly called the Fraser Spiral is a twisted illusion in which you think the curved lines are interconnected. This is not the case however. The image above is merely a bunch of circles on top of each other. The background must also be taken into account with this illusion as it greatly helps in the vision of this illusion. So go ahead and try to trace the circles; it's harder than you may think.