Optical illusion
The flashed face distortion effect tricks the eye into seeing attractive faces as ugly.

A simple optical illusion can make the famously attractive faces of stars such as Angelina Jolie and George Clooney seem ugly.

The flashed face distortion effect, shown in the video above, tricks the eye's perspective of faces flashed up on either side of a single point.

As the viewer watches the central cross, the faces either side of the point resemble crazed caricatures of the well-known celebrity faces.

The effect is explored in Perception, by University of Queensland researchers Jason Tangen, Sean Murphy and Matthew Thompson.

The researchers explain: "The degree of distortion is greatest for faces that deviate from the others in the set on a particular dimension (e.g if a person has a large forehead, it looks particularly large).

"This new method of image representation, based on alignment and speed, could provide a useful tool for investigating contrastive distortion effects and face adaptation."

The effect was first discovered by Murphy while he was working alone in a lab using a set of face pictures for an experiment. As he clicked through them they became distorted.