I love eye tricks. I have been crazy for them since my fifth-grade science teacher demonstrated to my class that we had a blind spot. That blew my mind!
I was hooked, and whenever I see an awesome eye trick on the Internet, I always give it a try.
This one did not disappoint!
Keep your eyes focused on the “X” in the middle. You will see that the pictures slowly change to monstrously deformed faces.
The more one watches, the more the faces become distorted. It is super cool and also a little freaky.
But, how does it work?
It all has to do with peripheral vision.
Peripheral vision is also known as side vision. It is the ability to see objects outside our direct line of vision. (Source) Because it is outside of our direct line of vision, it can be easy for us to get confused about what we see.
The fast motion of the pictures and how our brains work forces the pictures to become combined. The brain will combine the two images that are shown at the same time, along with the present picture with the previous image.
The longer one keeps his or her focus on the “X”, the more grotesque the faces become. Looking at one picture or the other will reset the process.
(h/t: Bright Side)