Voters around the world have chosen the Best Illusions of the Year, from the Top 10 Finalists competing in the 14th edition of the Best Illusion of the Year Contest. Voting started at 10am EST on October 16th and closed at 2pm EST on October 18th. The winning illusions were revealed on the Contest website at 9AM EST on October 19th.  

The 2018 Contest coincides with the announcement that Champions of Illusion, the book that showcases many of the illusions from the Contest and their creators, is longlisted for the AAAS/Subaru Prize for Excellence in Science.

First Prize and an award of $3,000 went to “Triply Ambiguous Object,” a mirror perspective illusion producing three seemingly incompatible views of the same object, crated by Kokichi Sugihara of Meiji University, Japan.

A flat drawing with a pole and flag attached generates three different 3-D interpretations when seen from three special viewpoints. Most ambiguous images, such as the Necker cube and the Schroeder staircase, generate only two interpretations, Sugihara explained. Observers perceive three different structures because they are compressed in different directions.

“When we see a picture in a slanted direction (in other words, in the direction other than orthogonal to the picture plane), our brains usually correct the distortion of the retinal image and perceive a normal 3D structure,” said Sugihara. “However, this is possible only when we know the dimension of the 3D objects represented in the picture. If we do not know the ratio of the dimensions along the three orthogonal axes, we cannot correct the distortion and consequently perceive different objects depending on the view directions.”

Second Prize and an award of $2,000 went to “Movement Illusion With a Twist,” a flowing motion illusion that expands, drifts and twists, created by David Phillips, Priscilla Heard, and Christopher Tyler of the University of the West of England, Bristol, and City University of London, UK.

“As we move around, we are mostly unaware of the optical flow patterns swept out as images and textures stream across our retinas, yet our brains are highly attuned to them,” Phillips and his co-creators explained. “[Our] illusions illustrate the ways that foreground movement can be affected when seen in relation to background movement, when both share directional components.”

The team discovered this unique set of illusions while trying to understand the apparent expansion and contraction effects seen in certain novelty rings, known in the jewelry trade as Witch Rings. The researchers’ striking contribution to the 2018 Best Illusion of the Year Contest originated from watching the movement of the bright reflections from the Witch Rings, as the rings rotated. 

Third Prize and an award of $1,000 went to “A Worm’s Eye View,” a four-frame movie generating the perception of powerful illusory motion, created by Michael Pickard and Gurpreet Singh of The University of Sunderland, UK.

There are a number of factors in the four-frame movie that make the illusion work, Pickard and Singh explained. “The creation of movement in either direction is determined by the precise geometry and positioning of the worm’s segments from frame to frame, [but its] direction depends on which of the two colors is visually most prominent and how these are positioned relative to the segments.”

When we view an image, our brain automatically separates it into foreground (the subject) and background, with our attention focusing on the subject, the pair elaborated. “As the slider moves [in the illusion video] the relative brightness of the two colors changes, and whichever is seen as the foreground determines the perceived direction of motion.”

All Top 10 illusion finalists from the 2018 Contest are available for viewing at the Best Illusion of the Year Contest’s website.

Illusion submissions are now accepted for the 15th edition of the Best Illusion of the Year Contest, to be held in 2019.