The digital realm consistently presents us with captivating optical illusions—intricate animated sequences designed to deceive our perception and misdirect our sensory input.

Certain illusions offer valuable insights, furnishing us with sophisticated psychological frameworks applicable to diagnosis and treatment. Others present a more formidable challenge to deconstruct, yet provide novel subject matter for spirited debate. And then there are those that are profoundly astonishing.

A cautionary note is warranted: should visual stimuli involving rotation and flashing cause discomfort, it is advisable to have this content read aloud and to simply visualize the remarkable nature of this illusionary artistry.

Understood? Excellent. Let us proceed.

Last year, a sequence of revolving blue and yellow circular forms, credited to the Japanese digital artist @jagarikin, circulated widely, eliciting both amusement and bewilderment.

rotating circles illusion

Since that time, variations on this theme have emerged. Consider, for instance, this recent chromatic wheel illusion.

Then there is this monochromatic rendition.

Naturally, there are diverse perspectives regarding the cognitive mechanisms at play in these phenomena, as evidenced by discussions on platforms like Reddit, where various opinions have been shared.

Some proposed explanations can be relatively easily discounted.

A significant portion of optical illusions exploit discrepancies within our visual field. For instance, a remarkable example previously discussed by Phil Plait on Slate also features spiraling striped circles.

Illusion showing black and white dots rotating around a red or yellow center.Animation based on work by Arthur Shapiro. (Phil Plait/Slate)

These particular visual stimuli appear to change shape due to the brain’s differential processing of information—that which is directly fixated versus that which is observed peripherally.

The fact that we can gaze directly at each of @jagarikin’s circles and still perceive the same illusion suggests that this particular neurological quirk can be ruled out.

Furthermore, any notion of the arrows exerting a subtle influence can be disregarded.

Below, Twitter user @XQA999 has removed these elements, thereby allowing us to negate any potential subliminal effects they might produce.

Through the judicious additions by @blindrob, we can also definitively confirm the stationary nature of the circles.

Intriguingly, by superimposing a black annulus upon the initial circle, @blindrob demonstrates that the illusion’s intensity appears to diminish when bordered.

Upon closer examination of the other circles, an unusual characteristic becomes apparent at their perimeters. Each circle exhibits, with a width of mere pixels, bands of contrasting hues along its inner and outer rims.

Example of blue and yellow wheel with pixels on rimNote the blue pixels on the outside of the yellow blocks.

As the circle rotates, the orientation and scale of the perceived circular forms shift in correlation with the arrangement of these two peripheral color bands.

Understanding these underlying mechanics is akin to revealing the magician’s trick to the audience. While we may now recognize the hidden apparatus, theorizing about the precise cognitive processes that transform mere visual data into such compelling illusory motion necessitates a deeper exploration of visual perception.

For over a century, the Gestalt School of psychology has investigated how our brains construct form and perceived movement from variations in visual stimuli.

One mechanism through which our neural system interprets motion is known as the phi phenomenon. This cognitive process transforms rapid successions of color or luminosity changes into a more pronounced subjective experience, such as the impression of spatial displacement.

However, this only provides a partial explanation for the observed phenomenon. The visual effect is not a jerky, unstable fluctuation but rather a fluid, unidirectional motion that seems to persist indefinitely.

An artistic creation by George Mather, a psychologist at the University of Lincoln, offers the conclusive element to this puzzle. It illustrates how variations in luminance, strategically applied across a few frames depicting back-and-forth scene transitions, can generate an effect of continuous, unidirectional motion.

Analogous to the phi phenomenon, this ‘reverse’ phi phenomenon not only conjures the sensation of movement but also of perpetual forward progression.

In the context of the foregoing circular illusions, the dynamic shifts in the chromatic borders appear to be the operative elements responsible for generating the illusory motion, which is not actually occurring.

The underlying neurological explanation is somewhat more intricate, involving the precise temporal coordination of stimulating and inhibiting visual neurons.

Illusions predicated on both of these principles have been a source of wonder and fascination for generations. Thanks to the extraordinary talents of artists like @jagarikin, we will undoubtedly continue to discover numerous novel applications for these perceptual manipulations, purely for our enjoyment.

Our brains are indeed quite remarkable.