When Pretty Faces Turn Ugly: The Flashed Face Distortion Effect

2012 Second prize
Jason Tangen, Sean Murphy and Matthew Thompson
The University of Queensland, Australia

When you stare directly at the faces, they look normal. But, if you stare at the cross, the faces quickly turn ugly.

Like many interesting scientific discoveries, this one was an accident. An undergraduate student was working on face photographs for an unrelated experiment when he was suddenly shocked by the deformed faces staring back at him.

The distortion comes from the many differences between each face and the one that follows. A particularly tanned face, for example, will make the next face seem pale and squinty eyes will make normal eyes bulge.

More info here: mbthompson.com/research

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Grouping by Contrast

2011 Second prize
Erica Dixon, Arthur Shapiro & Kai Hamburger
American University, USA, Universität Giessen, Germany
This movie requires Flash Player 9

Luminance levels of four disks modulate in time. The top two disks become white when the bottom two disks become black, and viceversa. When placed against a split background, the disks group together along the diagonals. This grouping pattern follows the contrasts of the disks relative to their backgrounds.

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Counter-intuitive illusory contours

2010 Second prize
University of Sydney, Australia

In many natural scenes, portions of occluding surfaces and contours can be camouflaged by having an identical color as their background. It is now well known that the visual system will often generate illusory contours and surfaces in order to fill-in this missing information. It is widely believed that the visual system does this in order to provide the best overall “explanation” of the images that form in our eyes. In this illusion, four circular disks are simply translated back and fourth over a thin square outline. Although all of the image data is fully “explained” by the visible disks, the visual system generates a strong and clearly visible additional illusory contour inside the square outline. This illusion cannot be understood with any known mechanism or theory that has been proposed to explain the formation of illusory contours. This quicktime movie is best viewed by downloading it and playing it in “loop” mode.

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Color dove illusion

2009 Second prize
Yuval Barkan & Hedva Spitzer

Tel-Aviv University, Israel
This movie requires Flash Player 9

Fix your gaze on the central black point on the bird, as well as while the sky flashes. When the bird starts to fly, follow it, and keep staring at the black fixation point. You’ll start to notice, that the “empty bird” is filled-in with a color similar to the previous background’s color. The colored image produces illusory colors, an afterimage on “empty” shape, which induces an effect opposite to the well known “afterimage” effect. The common “afterimage” effect yields perceived complementary color, whereas the current effect shows an appearance of a color similar to that of the background, where originally, no physical color was present in the empty shape.

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Jenkins: Ghostly Gaze

2008 Second prize
Rob Jenkins

University of Glasgow, UK
This movie requires Flash Player 9

How do we tell where other people are looking? Conventional wisdom says the dark parts of their eyes give it away. But the Ghostly Gaze illusion reveals a more subtle process.
From a distance, the sisters seem to stare at each other, but as you bring them closer to you with the slider, they turn their eyes to you! This is not a computer trick – to convince yourself set the slider to ‘close’ and walk away from your computer screen while looking at the image: notice that when you are sitting in front of the monitor the sisters are looking at you, but when you are about 3-4 meters away they look at each other!
The illusion is based on the hybrid image technique, developed by Schyns and Oliva. Gaze direction is an extremely important social cue. The Ghostly Gaze illusion shows that details such as the outline of the iris can override larger patches of darkness.

Read more about the illusion and possible explanations

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The Infinite Regress Illusion

2006 Second prize
Dartmouth College, USA


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Fixate the black fixation point on the far left side of the image. Note that the figure appears to move steadily away from the fixation point, even though it is in fact only moving up and down.

See another version of the illusion

The infinite regress illusion reveals faulty integration of local and global motion signals Peter U. Tse & Po-Jang Hsieh Vision Research. 2006. 46:3881-5

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Two-Stroke Apparent Motion

2005 Second prize
George Mather

Sussex University, UK

The illusion contains two pattern frames depicting a moving image (hence two-stroke) which are displayed using a technique that creates an impression of continuous forward movement.

Visit the website

Two-stroke: a new illusion of visual motion based on the time course of neural responses in the human visual system George Mather Vision Research. 2006. 46:2015-8

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