The Internet challenged netizens with yet another optical illusion, this time care of game developer Will Kerslake and his black dots grid viral photo.

Netizens love challenges. Remember the two hearts challenge? It was a simple exercise yet it revealed much about how the human brain works. Hence, looking at two hearts at the same time might never be the same again. The beautiful face of Adele also went viral after it received a bizarre makeover. Indeed, the resulting optical illusion photo went viral, as it left everyone baffled.

This time around, the black dots grid photo posted by game developer Will Kerslake has everyone thinking. The image challenged viewers to see the twelve black dots highlighted at different intersections. However, it is not as easy as it seems. As Kerslake himself revealed, the human brain itself would prevent any viewer from seeing all the black dots at once.

As it turns out, Japanese psychology professor Akiyoshi Kitaoka posted the image first on Facebook. Its basis was a scientific paper from 2000. Hence, it is a hint that the black dots grid challenge offers more than meets the eye.

Black Dots Grid Explained

Vision scientist Derek Arnold from the University of Queensland explained the phenomenon behind the black dots grid. Apparently, the optical illusion is a test of the human’s peripheral vision. Focusing at one intersection with a black dot blurs the area around it. The lack of contrast registers in the brain and it assumes the pattern is the same all throughout. Hence, a viewer would likely not see the next black dot.

At the same time, focusing on the intersections without a black dot creates yet another optical illusion. Faint white squares register in the brain and might even offset the actual black dots in the image. The Verge likened this phenomenon to the Hermann grid illusion. Visual system scientists are well aware of the gap between perception and reality. Hence, he understands how people feel at what appears to be a simple yet tricky optical illusion.

“They think, ‘It’s an existential crisis. How can I ever know what the truth is?’,” Arnold said. Well now, you know.