Prepare to boggle your brains and scratch your eyes in disbelief; the winners of the 15th Best Illusion of the Year Contest have been revealed.

The Best Illusion of the Year Contest, hosted by the Neural Correlate Society and supported by the Museum of Mind, was opened to a public online vote on Monday, December 9, with the competition’s winners being announced just days later on Friday, December 13. 

Now, drum roll please... This year’s champion was Frank Force from the US for his “Dual Axis Illusion" (video below). His first-prize illusion consists of a spinning shape that appears to both rotate on a horizontal and vertical axis at the same time.

“The underlying math equations to form this [illusion] are themselves ambiguous in terms of rotation, so it is interesting how our mind is unable to deal with this and settles into a picture about what direction and axis it is rotating. Also, our mind pictures it as a 3D object while there is nothing actually happening that is 3D,” Force told Scientific American.

The second prize was snapped up by Haruaki Fukuda, a cognitive scientist from the University of Tokyo, for their illusion called “Change the Color” (below). In this illusion, we see a bunch of dots that either appear yellow and move horizontally across the screen or we see a stream of red and green dots that fall vertically down the screen. 

Ryan E B Mruczek and Gideon Paul Caplovitz from the College of the Holy Cross and the University of Nevada Reno won third prize for creating “The Rotating Circles Illusion”. Although the illusion’s central circle is consistently spinning around in a simple rotating movement, the added motion of surrounding largest circles leads you to believe its moving up and down, left and right, or even in a triangle. 

Another illusion that made the top 10 is something a little different – and a lot more creepy. “Bodiject Fingers” by Kenri Kodaka of Naoya City University in Japan was simply created with a camera, a mirror, and a few spare hands. As you can clearly see in the video, poking figures underneath a slightly raised mirror creates a peculiar impression where the fingers are transformed into strange objects or creatures.

Another finalist is by Kokichi Sugihara from Japan's Meiji University for their “Facing-Right Illusion.” It consists of a three-dimensional object shaped like the silhouette of a bird. Curiously, even if you rotate the sculpture around a vertical axis by 180 degrees, it appears exactly the same.

Five other illusions were picked for the contest’s top 10, all of which you can check out below. Some of these illusions, along with many more, can also be found in a new book - Champions of Illusion - by the competition's founders.

If you like what you saw from this year's contest, you can take a look at last year’s winners right here too.