How is That Diamond Moving? This Optical Illusion Is Important for Science

This optical illusion is entertaining but also important science work for autism and color perception research.

This optical illusion will confuse and delight you.

Researchers Oliver Flynn and Arthur Shapiro, developed the "Perpetual Diamond" illusion, they describe the illusion as producing "motion continuously and unambiguously in one direction despite never physically changing location."

Check it out here:

The spectacular illusion is produced because of the diamond flashing background in combination with its thin borders. The diamond appears to move either, up, down, left or right. The direction of this motion is determined by the ‘relative phases of the luminance modulation between the edge strips and the background.’

Illusion may be used for color perception testing 

The researchers say that because the motion is generated by the contrast signals between the edge strips and background, the illusion can be potentially used as a tool for tests of spatial contrast, temporal contrast, contrast gain, and color contrast.

The researchers note that because the motion of the diamond is generated through changing contrast signals alone, it shows no clues to its possible orientation or direction until it is animated.

This means it may be possible to use it for future studies of color by experimenting with changing different parts of the illusion. For example, contrast gain, motion integration and changing the thickness of the edges of different outcomes may be produced, which have value for different kinds of testing.

Autism test from spinning GIF

Optical illusions are fun to play around with, but they can also offer really interesting insights into the ways our brains work and interestingly the differences between our brains. Last August, a group of scientist from Italy and Australia presented a paper that outlines how an optical illusion GIF might be a useful tool in autism diagnosis.

The GIF of a spinning column could be used as part of other tests to help medical experts screen for autistic traits. The test works on the premise that a person's pupils change size depending on whether they are looking at dark or light images.

This can be, in turn, used to analyze where a person's attention is focused. The images used in the test shows a sheet of white dots moving in one direction and a sheet of black dots moving in the other direction.

For most people who observe the GIF, it will look like a 3D cylinder of dots moving in rotation. But. the way that people come to that conclusion, differs.


Useful indicator

Some people need to focus on the white dots to observe the phenomenon, for others it is the black dots, and some others can see the image in its entirety and observe the whole GIF and all its dots at once. As your eyes try and decipher the image, your pupils are doing different things.

For those that examine the dots separately, changing from looking at the black dots to the white dots will make their pupils expand and contract rapidly. If you are looking at the image for a while though, your pupils will remain a more consistent size.


The researchers found that the people whose pupils oscillated when they looked at the rotating cylinder were more likely to display autistic tendencies.