This head-spinning optical illusion is causing mayhem online

Five years ago we published an optical illusion that millions of you were completely bamboozled by, and today I've found a brand-new version of that illusion. Of course, I'm referring to the rotating horse, which remains a puzzle to this day (just tell me which way it's spinning!). This illusion is an x-ray style image of a dismembered head, and it's causing almost as much mayhem online.

Not everyone on Reddit is convinced that it's actually rotating, with so many comments asserting that the illusion is a fake and is actually turning from side to side that I actually thought about abandoning this article. But after careful study, I can assure you that the head is definitely rotating all the way around, and it keeps changing depending on which part of the head or face you focus on. Ouch. See which side of the debate you fall on below. Good luck.

Left or right from r/opticalillusions

So how can you make it work?

"I can only see it rotate fully around if I focus on one of the ears. Focusing on the face makes go back and forth like you're seeing," one comment advises. "I focused on the ear and now the face and ear are moving in opposite directions," says someone else.

But the people who don't think it's rotating are very sure. "It is going back and forth. If you focus at the shoulders/neck you see it does something strange before reversing. Also the ears when they line up," says one naysayer.

Countered to that though, others definitely see the rotation. "That's odd. I can only see it as full, continuous rotations. I can't see what everyone else is saying about back and forth movements."

This is just like the spinning ballerina illusion above. WhatPsychologyIs explains why. "Due to the image’s lack of visual cues for depth, the ambiguous 2-dimensional figure can be seen from two different perspectives," it reads. "This alternation between two perceptual states is referred to as bistable perception."

For more, see our list of the best optical illusions ever.