This Crazy Optical Illusion Will Disappear Before Your Very Eyes

[forgotmylogin]

4. Pretty much.

Saccades are these tiny involuntary movements that the human eye makes, even when our focus is apparently settled. These fast eye movements allow the retina, with all of its light-sensitive cells, to scan our visual field with the highest resolution.

But here's the catch: if you focus the retina on one tiny point in your visual field (like a black dot), the retina's light sensitive cells will become used to the unchanging scene, and they will gradually become desensitised to the stimulus.

Before you know it, the stimulus will begin to fade and take on the appearance of the background. In neuroscience, this concept is known as "filling-in".

And if you still don't get it, consider this: "filling-in" is exactly why you don't notice the presence of your nose, even though it sits in the very center of your vision every single minute of every single day.