Take a look around you. Can you see everything in your surroundings? Most of us would say yes. But the truth is, whether your vision is 20/20 or corrected by lenses, the answer is the same: no matter how hard you try, you cannot see everything around you.

The human eye has a blind spot—a small area on the retina, about the size of a pencil eraser, without photoreceptors. We usually aren’t aware of this blind spot because our brains fill in this blank area with the surrounding images, making our visual field appear seamless. But this is an optical illusion. With one eye closed, any object passing through this small field will disappear momentarily. [Read more…]