Circle Spiral Illusion

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This Circle Spiral Illusion is a version of the the “Fraser Spiral Illusion” or “False Spiral Illusion.” In this illusion, a series of concentric circles, when arranged in a particular pattern, appear to form a spiral or twisting pattern, even though the individual circles are actually concentric and not spirals.

Circle Spiral Illusion


Table of Contents

What is the Circle Spiral Illusion?

The Circle Spiral Illusions is a version of the “Fraser Spiral Illusion” or “False Spiral Illusion.” In this illusion, a series of concentric circles, when arranged in a particular pattern, appear to form a spiral or twisting pattern, even though the individual circles are actually concentric and not spirals.

The Fraser Spiral Illusion was discovered by the British psychologist James Fraser and was first published in 1908. The illusion occurs due to the interaction between the radial lines connecting the circles and the perceptual system’s interpretation of these lines. The radial lines create an apparent spiral motion, leading to the perception of a spiral pattern emerging from the concentric circles.

The Circle Spiral Illusion highlights how our brain’s interpretation of visual information can lead to misleading perceptions and the creation of illusory patterns. It is an interesting example of how our visual system can be deceived by certain spatial arrangements and cues, resulting in the perception of motion or patterns that do not actually exist.

How does the Circle Spiral Illusion Work?

The Circle Spiral illusion works by exploiting our visual system’s tendency to perceive patterns and motion based on certain visual cues. Here’s an explanation of how it works:

  1. Concentric Circles: The illusion begins with a set of concentric circles, typically with evenly spaced radial lines extending from the center. These circles are truly concentric and have no inherent spiral shape.
  2. Radial Lines: The radial lines are positioned and angled in a way that interacts with our visual system. These lines typically connect the intersections of the circles, creating a series of diagonal lines that appear to spiral inward or outward.
  3. Perceptual Completion: When we observe the concentric circles with the radial lines, our brain tends to complete missing information or fill in gaps based on visual cues and previous experiences. In this case, our brain perceives the missing parts of the spiraling pattern, even though it doesn’t actually exist in the image.
  4. Grouping and Motion Perception: Our visual system naturally groups similar elements and looks for patterns or motion. The arrangement of the radial lines in the Fraser Spiral Illusion gives the impression of a spiraling or twisting motion, as if the circles are forming a spiral pattern.
  5. Contextual Cues: Surrounding context and other visual cues can also influence our perception of the illusion. Elements such as the background or the presence of other patterns may enhance or modify the perceived spiral effect.

The combination of these factors leads to the perception of a spiral pattern emerging from the concentric circles, despite the circles themselves being static and truly concentric. The Circle Spiral Illusion demonstrates how our brain interprets visual information and fills in gaps to construct a coherent perception of the world, sometimes resulting in deceptive patterns or motions that are not actually present in the stimulus.

Some Similar Illusions

There are several illusions that share similarities with the Circle Spiral illusion in terms of creating misleading perceptions of spirals or twisting patterns. Here are a few examples:

  1. The Twisted Cord Illusion: In this illusion, a twisted or coiled rope or cord appears to have a spiral shape when it is unwound. This perception arises due to the interaction between the physical properties of the twisted cord and our visual system’s interpretation of the changing angles and perspective cues.
  2. The Spiral Aftereffect: This illusion occurs after prolonged exposure to spirals rotating in one direction. When you shift your gaze to a stationary image, such as a blank wall, you may perceive illusory spirals rotating in the opposite direction. This phenomenon is a result of neural adaptation and the aftereffects of the motion-sensitive neurons in the visual system.
  3. The Poggendorff Illusion: The Poggendorff illusion involves an oblique line that is interrupted by a rectangular shape. The interruption creates a misalignment in the line segments, making them appear disjointed and causing an illusion of a distorted or misaligned line. The perceived misalignment can create the impression of a spiral-like shape.
  4. The Pinna-Brelstaff Illusion: In this illusion, a pattern of concentric circles or spiral-like shapes, when combined with specific motion, creates the perception of the circles expanding or contracting in size. This effect is due to the interaction between the motion-sensitive neurons in the visual system and the specific arrangement of the patterns.

These illusions, like the Circle Spiral Illusion, manipulate visual cues, perspective, motion, and context to create deceptive perceptions of spirals or twisting patterns. They demonstrate the intricate ways in which our visual system processes and interprets visual information, leading to fascinating illusions and distortions in our perception of reality.

Discovery of the Spiral Illusion

The Circle Spiral illusion is a version of the the Fraser Spiral Illusion, also known as the False Spiral Illusion, was discovered and named after James Fraser, a British psychologist. Fraser first described and published the illusion in his article titled “A New Visual Illusion of Direction,” which appeared in the American Journal of Psychology in 1908. Fraser’s work contributed to the understanding of visual perception and the ways in which our brains interpret visual stimuli to create illusory effects.


References and Resources

In addition to the Circle Spiral Illusion, check out our complete list of illusions and this awesome similar illusions: Platform 9 3-4, Moving Diamond, Moving Ball, Scintillating Stars

Circle Spiral Illusion