Justwhen you thought you had your life together, the internet throws you an optical illusion that makes you question your entire existence.
The latest is on Twitter from game developer Will Kerslake, who shared a picture of a geometrical grey pattern on a white background.
Sounds pretty straight forward, until you realise there are 12 black dots blinking in and out of existence at intersection points on the pattern.
Black dots usually appear where your vision is focused, with the surrounding dots seemingly disappearing.
Although it’s hard to believe, there is actually 12 black dots permanently in the image — majority of people just can’t see them.
French scientist Jacques Ninio said the illusion has to do with humans having sketchy peripheral vision.
“When the white disks in a scintillating grid are reduced in size, and outlined in black, they tend to disappear. One sees only a few of them at a time, in clusters which move erratically on the page,” Mr Ninio explained.
“Where they are not seen, the grey alleys seem to be continuous, generating grey crossings that are not actually present.
“Some black sparkling can be seen at those crossings where no disk is seen. The illusion also works in reverse contrast.”
So essentially, you will see black dots when you are focusing in the centre of your field of view, but outside of this area your visual system is filling in what it thinks is going on around it.
Because the majority of the pattern is grey lines on a white background, your brain assumes this is what will be outside your field of vision, which is why there are no black dots.
