Today I’ve chosen a ghostly visual optical illusion. I like to call it like this because of the way it works, if you will pay attention you will see that this illusion resembles a lot with “The Lilac Chaser”.
What to see?
In this picture we have a lot of colored dots and a small black dot in the middle.
For the visual optical illusion illusion to work you have to stare at the little black dot in the middle for a few seconds and as the time passes by you will notice that the colors around it start to fade. At first I expected them to remain on the background a little pale, but they disappeared for good.
How it works?
In “the lilac chaser” we had more explanation for the illusion; in this one we have only one. When we are fixating our look on a certain point in our perception field, that point becomes the main object of our visual system. When a blurry stimulus appears in a region of the visual field further from the point we are fixating, and we keep our eyes still, that stimulus will disappear even though it is still there.
This phenomenon is called Troxler’s fading. It occurs because even if our eyes move a little when we are fixating a point, away from that point, in the perception field, the movements aren’t large enough to observe other elements; in conclusion the neurons remain focused on the main object and our visual system doesn’t involve new ones for the other elements.
I also noticed that if I stare long enough at the picture the dots tend to reappear after a while, I’m thinking that this happens because our main perception field tends to get larger as our visual system gets used with the task.