Moving Spiral Illusion

Look at the center of this Moving Spiral Illusion and watch as the surrounding circles appear to spiral around the center.

This Moving Spiral Illusion works based on the principles in two famous illusions – the Fraser Spiral and Peripheral Drift.

If you are interested in learning more about how this Moving Spiral Illusion works, scroll down to read more about it.

Moving Spiral Illusion


Table of Contents

What is the Moving Spiral Illusion?

This Moving Spiral Illusion works based on the principles in two famous illusions – the Fraser Spiral and Peripheral Drift.

The Fraser spiral illusion is an optical illusion that involves a spiral pattern composed of concentric circles.

In the Fraser spiral illusion, the individual circles appear to spiral outward towards the edges of the pattern, giving the impression of a continuously expanding spiral. However, in reality, the circles are arranged in a series of disconnected concentric circles, with no actual spiral present.

The illusion occurs due to the way our brain processes visual information. The concentric circles and spacing between them create an optical effect that leads our brain to perceive a spiral where there is none. This is an example of a perceptual illusion, where our perception of reality is altered due to the way our brain processes information.

Peripheral drift is an optical illusion that occurs when stationary patterns, such as stripes or grids, appear to move or “drift” in the peripheral vision of an observer. The illusion is created by the way the brain processes visual information from the retina, which can cause the edges of the patterns to appear to blur or vibrate slightly.

The effect is more pronounced when the patterns are high-contrast, such as black and white stripes, and when the patterns are presented in the periphery of the visual field. The illusion can be enhanced by adding motion to the patterns or by varying the width or spacing of the stripes.

Peripheral drift is thought to be caused by a combination of factors, including the way the brain processes spatial frequency information, the interactions between adjacent visual neurons, and the effects of eye movements and fixational eye movements.

Peripheral drift is a well-known phenomenon in vision science and has been studied extensively as a way to better understand the mechanisms of visual processing in the brain.

How does the Moving Spiral Illusion Work?

This Moving Spiral Illusion works based on the principles in two famous illusions – the Fraser Spiral and Peripheral Drift.

The Fraser spiral illusion works by exploiting the way our visual system processes information. The illusion is created by a pattern of concentric circles that are spaced closer together near the center of the spiral and farther apart towards the outer edges.

When we look at the pattern, our brain tries to make sense of the visual information by grouping the circles into patterns. However, because the spacing between the circles changes, our brain interprets the pattern as a spiral rather than a series of concentric circles.

The illusion is further strengthened by the fact that the circles are shaded so that they appear to have a gradient of darkness from the center to the outer edge. This gradient reinforces the impression of a spiral, as our brain interprets the change in shading as indicating a continuous curve.

In short, the Fraser spiral illusion is created by manipulating the visual cues that our brain uses to interpret patterns, leading us to perceive a spiral where none actually exists.

Peripheral drift is an optical illusion that occurs when stationary patterns, such as stripes or grids, appear to move or “drift” in the peripheral vision of an observer. This illusion is caused by the way the brain processes visual information from the retina.

The retina is the part of the eye that receives visual input from the environment and sends it to the brain for processing. The retina is made up of cells called photoreceptors, which detect light and send signals to other cells in the retina, called retinal ganglion cells.

The retinal ganglion cells are organized in a way that allows them to detect different aspects of the visual scene, such as edges, color, and motion. Some cells are sensitive to low spatial frequencies, meaning they respond best to wide, low-contrast patterns, while others are sensitive to high spatial frequencies, which means they respond best to narrow, high-contrast patterns.

When an observer views a stationary pattern of high-contrast stripes in their peripheral vision, the edges of the stripes appear to blur or vibrate slightly due to the interactions between adjacent visual neurons in the retina. These slight movements are then interpreted by the brain as motion, which creates the illusion of drifting.

Additionally, eye movements and fixational eye movements, which are small involuntary movements of the eyes, can also contribute to the perception of drifting. As the eyes move and fixate on different points in the visual scene, the edges of the patterns can shift slightly, which can enhance the illusion of movement.

Overall, peripheral drift is a complex phenomenon that involves multiple factors in both the retina and the brain. Studying this illusion can provide valuable insights into the mechanisms of visual processing and perception.

Discovery of the Moving Spiral Illusion

This Moving Spiral Illusion works based on the principles in two famous illusions – the Fraser Spiral and Peripheral Drift.

Sir James Fraser was a British psychologist who made important contributions to the field of perception and cognitive psychology.

He was born in 1854 and died in 1941. He is best known for his work on visual perception, particularly for his description of the Fraser spiral illusion in 1908.

Fraser studied at Cambridge University and later became a professor of psychology at University College London.

He made a significant contribution to the study of visual perception, and his work on the Fraser spiral illusion helped to establish the field of cognitive psychology, which focuses on how the brain processes and interprets information.

He also made contributions to other areas of psychology such as memory and attention. He was knighted in 1935 for his services to psychology.


References and Resources

In addition to the Moving Spiral Illusion, check out our complete list of illusions.