Look at an optical illusion and you may think you're seeing things -- such as a curved line that's actually straight, or a moving object that's standing still. You wonder if your eyes are playing tricks on you.
It's not your eyes. An illusion is proof that you don't always see what you think you do -- because of the way your brain and your entire visual system perceive and interpret an image.
Visual illusions occur due to properties of the visual areas of the brain as they receive and...Full Story