Chevreul Illusion

chevreul

The Chevreul illusion is created by the way the brain perceives edges of an object. When the edges of an object are surrounded by a contrasting color, the edges appear to be a different color than they actually are.

The illusion also can create the appearance of movement or “flicker” in the pattern, even though the pattern itself is static.

chevreul
From Wikimedia Commons


Table of Contents

How does the Chevreul Illusion work?

The illusion is caused by the way the human visual system processes patterns of light and dark. When the eyes are fixated on a point, the visual system tends to average the luminance of the surrounding area, this causes the visual system to perceive the alternating bands as if they were moving. The effect is more pronounced when the bands are thin and the contrast between light and dark is high.

Chevreul illusion are similar, but different from Mach Bands. They are both visual illusions that involve the perception of brightness and contrast, but they are not the same phenomenon.

Chevreul’s illusion is an optical illusion that was first described by Michel Eugène Chevreul in 1839. It is also known as the “simultaneous contrast illusion” and it occurs when two colors are placed next to each other, and their perceived hues appear to change. This happens due to the way that the brain processes color and light, and the way that it adjusts the perception of color based on the surrounding colors.

Mach bands, on the other hand, is an optical illusion that was first described by Ernst Mach in 1865. It is also known as the “Mach effect” and it causes the perception of a band of increased or decreased brightness at the edge of a sharply defined color boundary. This is caused by the way that the visual system processes light and color, and the way that it interprets the edges of objects.

In summary, Chevreul’s illusion and Mach bands are two different visual illusions that involve the perception of brightness and contrast, but they work in different ways. Chevreul’s illusion is an effect on the perception of hue, while Mach bands is an effect on the perception of brightness.

Versions of the Chevreul Illusion

The following is an alternate version of the Chevreul Illusion:



chevreul


Chevreul-Mach-bands-wiki.jpg



Illusions like the Chevreul Illusion

Color illusions work by exploiting the way that the human visual system processes color and light. The human eye is able to detect light in the visible spectrum, which consists of different wavelengths of light that correspond to different colors. The brain then interprets this information to create our perception of color. However, the way the brain perceives color is not always a perfect representation of the physical reality.

There are several factors that can influence the way that the visual system processes color and light, which can lead to the perception of illusions. These factors include:

Contrast: The way that the brain perceives color can be influenced by the surrounding colors and patterns. High-contrast borders around an area of color can cause the brain to interpret the color as spreading or “bleeding” beyond the actual boundaries of the object.

Lighting conditions: The way that the brain perceives color can also be affected by the lighting conditions. For example, when an object is viewed in bright light, the eye’s color receptors may become fatigued, causing the brain to perceive colors differently than they actually are.

Color adaptation: The brain adapts to the colors that we see over time, which can influence the perception of color. For example, if an individual looks at a red object for an extended period of time, the brain will adapt to the red, and when that person looks at a white object, it will appear to have a pinkish hue.

Color constancy: The brain is able to adjust the perception of color based on the context in which it is viewed. This can create illusions where the same color appears to be different depending on the surrounding colors.

Shape use: Some illusions like the Hermann grid illusion or the Cafe Wall illusion, use specific patterns and shapes to manipulate the perception of color and shape.

Some related illusions include the following:

The Neon Color Spreading illusion refers to the visual phenomenon where an area of color appears to spread or “bleed” beyond its intended boundaries.

Neon Color Spreading
From Wikimedia Commons

The Bezold Effect: This illusion is created by placing two or more colors next to each other, and the way they appear to change when they are close to one another.  

Bezold_Effect
from Wikimedia Commons

The Mach Band Illusion: This illusion is created by the way the brain perceives edges of an object. When an object has a gradient of color, the edges of the object appear to be darker or lighter than they actually are.

Mach Bands Animation
From Wikimedia Commons

The Hermann Grid Illusion: This illusion is created by the way the brain perceives intersections of lines. When the intersections of a grid of lines are viewed, small gray dots appear at the intersections, even though they are not actually there.



Hermann Grid

The Watercolor Illusion: This illusion is created by the way the brain perceives edges of an object. When an object is surrounded by a colored halo, the object appears to have a different color than it actually does.

Watercolor Illusion


The Ishihara Illusion: This illusion is created by the way the brain perceives colors. When a color is surrounded by a contrasting color, the brain perceives the color to be different than it actually is.

Ishihara Plate 9
From Wikimedia Commons

The flash lag illusion is a visual illusion that is based on the perception of the temporal relationship between a moving object and a flash of light. The illusion occurs when a moving object is followed by a sudden flash of light, and the perceived location of the flash appears to be behind the actual location of the object.

Flash Lag
From Wikimedia Commons

The Café Wall Illusion is a visual illusion that is created by a grid of alternating light and dark horizontal and vertical lines. The lines appear to be bent or tilted, even though they are actually straight.

Cafe Wall Illusion


Discovery of the Chevreul Illusion

The illusion is named after Michel Eugène Chevreul, a French chemist and physicist, who first described it in 1839.

Michel Eugène Chevreul (1786-1889) was a French chemist and physicist who made significant contributions to the field of color theory. He is best known for his work on the nature of color, and the relationship between colors, which he described in his book “The Laws of Contrast of Colors” (1839). He was one of the first to study the perception of color, and the effect of surrounding colors on the perception of a given color. He is particularly known for the discovery of the Chevreul Illusion, a visual effect that creates the appearance of movement or “flicker” in a pattern of alternating light and dark bands.

Chevreul’s work on color perception had a significant influence on the development of color theory, and continues to be studied in fields such as art, design, and psychology. He was also a researcher in other scientific fields such as soap-making and oils, and he developed a method for the analysis of fats and oils, which was widely used in the food industry. He was a professor of chemistry in Paris and a member of the French Academy of Sciences

References and Resources

Check out our complete list of illusions.

Sign Up to Have Your Mind Blown

Flash Lag Illusion

Flash Lag

The flash lag illusion is a visual illusion that is based on the perception of the temporal relationship between a moving object and a flash of light.

The illusion occurs when a moving object is followed by a sudden flash of light, and the perceived location of the flash appears to be behind the actual location of the object.

Flash Lag
From Wikimedia Commons


Table of Contents

How does the Flash Lag Illusion work?

The flash lag illusion occurs because the visual system processes the moving object and the flash of light separately, and there is a delay in the processing of the flash. This causes the brain to perceive the flash as if it had occurred at a point in the past, behind the position of the moving object.

The flash lag illusion is considered as a temporal illusion, where the perceived timing of events is affected by the spatial relationship between the events. It has been used to study the neural mechanisms underlying visual perception, attention, and the temporal properties of visual processing.

The shift is greater for faster-moving stimuli and for stimuli that are closer to the point of flash onset.

In summary, the flash lag illusion is a visual illusion that occurs when a moving object is followed by a flash of light, and the perceived location of the flash appears to be behind the actual location of the object. This illusion is caused by the delay in the processing of the flash, and it has been used to study the neural mechanisms underlying visual perception, attention, and temporal properties of visual processing.

Versions of the Flash Lag Illusion

The following is an alternate versions of the Flash Lag Illusion:



Flash Lag
From Wikimedia Commons




Illusions like the Flash Lag Illusion

Color illusions work by exploiting the way that the human visual system processes color and light. The human eye is able to detect light in the visible spectrum, which consists of different wavelengths of light that correspond to different colors. The brain then interprets this information to create our perception of color. However, the way the brain perceives color is not always a perfect representation of the physical reality.

There are several factors that can influence the way that the visual system processes color and light, which can lead to the perception of illusions. These factors include:

Contrast: The way that the brain perceives color can be influenced by the surrounding colors and patterns. High-contrast borders around an area of color can cause the brain to interpret the color as spreading or “bleeding” beyond the actual boundaries of the object.

Lighting conditions: The way that the brain perceives color can also be affected by the lighting conditions. For example, when an object is viewed in bright light, the eye’s color receptors may become fatigued, causing the brain to perceive colors differently than they actually are.

Color adaptation: The brain adapts to the colors that we see over time, which can influence the perception of color. For example, if an individual looks at a red object for an extended period of time, the brain will adapt to the red, and when that person looks at a white object, it will appear to have a pinkish hue.

Color constancy: The brain is able to adjust the perception of color based on the context in which it is viewed. This can create illusions where the same color appears to be different depending on the surrounding colors.

Shape use: Some illusions like the Hermann grid illusion or the Cafe Wall illusion, use specific patterns and shapes to manipulate the perception of color and shape.

Some related illusions include the following:

The Neon Color Spreading illusion refers to the visual phenomenon where an area of color appears to spread or “bleed” beyond its intended boundaries.

Neon Color Spreading
From Wikimedia Commons

The Bezold Effect: This illusion is created by placing two or more colors next to each other, and the way they appear to change when they are close to one another.  

Bezold_Effect
from Wikimedia Commons

The Mach Band Illusion: This illusion is created by the way the brain perceives edges of an object. When an object has a gradient of color, the edges of the object appear to be darker or lighter than they actually are.

Mach Bands Animation
From Wikimedia Commons

The Hermann Grid Illusion: This illusion is created by the way the brain perceives intersections of lines. When the intersections of a grid of lines are viewed, small gray dots appear at the intersections, even though they are not actually there.



Hermann Grid

The Watercolor Illusion: This illusion is created by the way the brain perceives edges of an object. When an object is surrounded by a colored halo, the object appears to have a different color than it actually does.

Watercolor Illusion


The Chevreul Illusion: This illusion is created by the way the brain perceives edges of an object. When the edges of an object are surrounded by a contrasting color, the edges appear to be a different color than they actually are. Chevreul’s illusion is similar to Mach bands, but they work in different ways. Chevreul’s illusion is an effect on the perception of hue, while Mach bands is an effect on the perception of brightness.


Chevreul-Mach-bands-wiki.jpg


The Ishihara Illusion: This illusion is created by the way the brain perceives colors. When a color is surrounded by a contrasting color, the brain perceives the color to be different than it actually is.

Ishihara Plate 9
From Wikimedia Commons

The Café Wall Illusion is a visual illusion that is created by a grid of alternating light and dark horizontal and vertical lines. The lines appear to be bent or tilted, even though they are actually straight.

Cafe Wall Illusion


Discovery of the Flash Lag Illusion

The phenomenon was first described by Nijhawan (1994) who found that when a moving stimulus is followed by a flash, the perceived position of the flash is shifted behind the position of the moving object.

References and Resources

Check out our complete list of illusions.

Shepard Elephant

Shepard Elephant

The Shepard elephant illusion is an optical illusion that was created by the artist David H. Shepard. The illusion is a black-and-white line drawing of an elephant that appears to be three-dimensional and in motion, despite being a flat, static image.

The illusion is created by using a technique called “anamorphosis,” which involves distorting an image in a specific way so that when it is viewed from a certain angle or perspective, it appears to be in a different form or shape.

Shepard Elephant


Table of Contents

How does the Shepard Elephant Illusion work?

The Shepard elephant illusion is an optical illusion that works by manipulating the way the visual system perceives depth, shape, and movement.

The illusion is created by using a combination of fine lines, shading, and perspective to create the illusion of a three-dimensional object.

The technique used in the Shepard elephant illusion is anamorphosis, which is a form of perspective projection that is used to create distorted images that are only recognizable when viewed from a certain angle or perspective.

The elephant image was distorted in a specific way, such that when viewed from a certain angle, the distorted lines and shading combine to create the illusion of a three-dimensional elephant that appears to be in motion.

The brain relies on visual cues such as perspective, shading, and texture to infer the 3D structure of an object.

The Shepard elephant illusion works by manipulating these cues, creating an image that appears to be three-dimensional and in motion, despite being a flat, static image.

The brain is thus deceived by the manipulation of these cues and interprets the image as a 3D object with movement.

Versions of the Shepard Elephant Illusion

The following is an alternate versions of the Shepard Elephant Illusion:


Shepard Elephant



Illusions like the Shepard Elephant Illusion

Paradox illusions are a type of optical illusion that involve images that appear to be self-contradictory or impossible. They typically involve the manipulation of visual cues such as size, shape, movement, and depth perception to create an image that appears to be impossible or defies our understanding of the physical world.

In general, these illusions work by exploiting the way the visual system processes information. The brain relies on certain cues, such as perspective, shading, and texture, to infer the 3D structure of an object. When these cues are manipulated in a certain way, the brain can be fooled into perceiving an impossible or self-contradictory image.

Some related illusions include the following:

The impossible trident is a three-pronged impossible shape resembling a trident.

Impossible Trident
From Wikimedia Commons

The Necker cube is an optical illusion that features a simple wireframe drawing of a cube. The cube appears to switch back and forth between two different orientations.

Necker Cube

The Schröder Staircase is an optical illusion that features a drawing of a staircase. The staircase appears to be either ascending or descending, depending on how the brain interprets the angles of the lines.

Schroeders_stairs
From Wikimedia Commons

The impossible cube is an optical illusion that depicts a three-dimensional object that is physically impossible to construct.

Impossible Cube Illusion


The Penrose triangle, also known as the Penrose tribar, is an optical illusion that depicts a three-dimensional object that is physically impossible to construct.

Penrose Triangle


The spinning dancer illusion is a visual illusion that depicts a silhouette of a dancer spinning clockwise or counterclockwise. The direction of the dancer’s spin can appear to change depending on the viewer’s perception

Spinning Dancer Gif
From Wikimedia Commons

Discovery of the Shepard Elephant Illusion

The Shepard elephant illusion was created by the artist David H. Shepard.

He is an artist and illustrator who is known for his work in the field of optical illusions and anamorphosis.

He has created a number of other optical illusions and anamorphic artworks, as well as writing and lecturing on the subject.

He has been widely recognized for his contributions to the field and his artwork has been featured in various exhibitions and publications.

David H. Shepard was a British artist and illustrator who was known for his work in the field of optical illusions and anamorphosis.

He was a self-taught artist, and he became interested in the field of optical illusions and anamorphosis in the 1970s.

He created a number of optical illusions and anamorphic artworks, and he also wrote and lectured on the subject. He was recognized as one of the leading experts in the field of anamorphosis and optical illusions and his artwork has been featured in various exhibitions and publications.

He passed away on October 2019.

References and Resources

Check out our complete list of illusions.

Sign Up to Have Your Mind Blown

Spinning Dancer

Spinning Dancer Gif

The spinning dancer illusion is a visual illusion that depicts a silhouette of a dancer spinning clockwise or counterclockwise. The direction of the dancer’s spin can appear to change depending on the viewer’s perception.

Spinning Dancer Gif
From Wikimedia Commons

Table of Contents

How does the Spinning Dancer Illusion work?

The spinning dancer illusion works by exploiting the way the brain interprets the 2-dimensional image of a dancer silhouette, specifically the lines and angles of the dancer’s body, and the viewer’s sense of motion.

The image is ambiguous, and the brain can interpret the position of the dancer’s arms, the tilt of her head, and the direction of her gaze in different ways, creating the impression of motion in opposite directions.

The illusion works by playing with the viewer’s expectations about the relationships between the lines and angles of the dancer’s body and the viewer’s sense of motion.

The brain uses cues such as the position of the dancer’s arms, the tilt of her head, and the direction of her gaze to create the impression of motion in one direction, but then the brain starts to interpret the same cues in a different way creating the impression of motion in the opposite direction.

The brain is unable to reconcile the conflicting information, and it tends to flip between the two directions of motion, creating the illusion that the dancer is changing her spin direction.

This illusion also highlights the concept of “perceptual set” which refers to the brain’s ability to focus on specific aspects of the image and ignore others depending on the context and “top-down processing” where the brain uses prior knowledge to interpret the visual information coming from the eyes.

The spinning dancer illusion illustrates how the brain’s prior knowledge of how motion should look like can be misleading and create an illusion, and how it organizes the information in a way that creates the most meaningful and coherent interpretation.

Versions of the Spinning Dancer Illusion

The following are some alternate versions of the Spinning Dancer Illusion:

Spinning Dancer GIF colorful versions


Illusions like the Spinning Dancer Illusion

Ambiguous illusions are visual stimuli that can be interpreted in more than one way. These illusions typically consist of a single image that can be perceived in multiple ways. Ambiguous illusions can be used to study the neural mechanisms of perception and how the brain resolves ambiguity.

Some related illusions include the following:

The Rubin vase, also known as the Rubin face or the figure-ground vase, is a famous optical illusion in which the image of a vase can also be perceived as two faces in profile looking at each other.

Rubin Vase Classic Black and White


The duck-rabbit illusion is an optical illusion that is an image that can be perceived as either a duck or a rabbit depending on how the viewer looks at it.

Duck Rabbit Illusion

The Necker cube is an optical illusion that features a simple wireframe drawing of a cube. The cube appears to switch back and forth between two different orientations.

Necker Cube

The My Wife and My Mother-in-Law illusion is an optical illusion with an image of a young woman’s face that can also be perceived as an older woman’s face.

Wife and Mother In Law

The Schröder Staircase is an optical illusion that features a drawing of a staircase. The staircase appears to be either ascending or descending, depending on how the brain interprets the angles of the lines.

Schroeders_stairs
From Wikimedia Commons

The impossible cube is an optical illusion that depicts a three-dimensional object that is physically impossible to construct.

Impossible Cube Illusion


The Penrose triangle, also known as the Penrose tribar, is an optical illusion that depicts a three-dimensional object that is physically impossible to construct.

Penrose Triangle


The impossible trident is a three-pronged impossible shape resembling a trident. It is usually depicted as a three-pronged fork with each prong appearing to be a continuation of the next, creating an impossible shape.

Impossible Trident
From Wikimedia Commons

The Monroe-Einstein illusion works by playing with the viewer’s expectations about the relationships between the features of the faces and the viewer’s sense of facial proportions.

Monroe-Einstein

Discovery of the Spinning Dancer Illusion

The illusion was created by the web designer Nobuyuki Kayahara in 2003 and it quickly went viral on the internet.

References and Resources

Check out our complete list of illusions.

Sign Up to Have Your Mind Blown

Illusory Motion

Motion_illusion_in_star_arrangement

With Illusory motion, static image appears to be moving due to the interaction of color contrasts, shapes, and position.

Motion_illusion_in_star_arrangement


Table of Contents


How does Illusory Motion work?

Illusory motion, also known as motion illusion, is the perception of movement in a static image or pattern.

This can occur when the brain is presented with a series of static images that change over time, or when certain visual patterns are arranged in a specific way.

The brain interprets these as if they are moving, even though the image or pattern itself is not actually moving.

There are several theories that try to explain the underlying mechanisms of illusory motion.

One theory is that it is a result of neural adaptation, where the visual system becomes adapted to certain stimuli and continues to respond as if they were present even after they are removed.

Another theory is that it is a result of the brain’s tendency to perceive patterns and to fill in missing information, known as Gestalt principles.

Versions of Illusory Motion

The following are some other examples of Illusory Motion





Illusory-Motion



Illusory-Motion




Illusory-Motion





Illusory-Motion








Illusory Motion




Illusory Motion










Peripheral drift illusion
From Wikimedia Commons


peripheral-drift-illusion-giving-a-throbbing-effect
From Wikimedia Commons



Peripheral_drift_illusion_blue-and-orange-wormhole


Illusions like Illusory Motion

The following are some illusions related to Illusory Motion

In Peripheral Drift illusions, the image or pattern appears to move or drift, even though it is actually stationary. This movement is caused by the brain’s attempt to interpret the image or pattern, which is often complex or ambiguous. The movement can be in any direction, such as horizontally, vertically, or diagonally.

Peripheral drift illusion jelly bean
From Wikimedia Commons

The rotating snakes is a peripheral drift illusion that consists of a grid of shapes, with some of them appearing to be rotating or undulating. The illusion is created by the interaction of the shapes with the neural processing of the visual system.

Rotating Snakes Autokinetic effect
A Version of Rotating Snakes


The Moiré pattern illusion: This illusion is created by superimposing two similar patterns on top of each other, such as a grid of lines or circles. The resulting pattern appears to be moving or changing.


Moiré_pattern
From Wikimedia Commons


The Scintillating Grid Illusion, in which a grid of black and white squares appears to pulsate or “breathe” when viewed from the periphery of the image.

Simultaneous Contrast Illusion



The Hermann Grid Illusion, in which the intersections of a white grid on a black background appear to be gray, even though they are actually the same color as the background.

Hermann-Grid Illusion


The Zöllner Illusion, in which parallel lines appear to be tilted or bent when intersected by diagonal lines.

Zöllner illusion


The Fraser Spiral Illusion, in which a pattern of short, curved lines appears to form a spiral.

Fraser-spiral-illusion.




The Café Wall Illusion is a visual illusion that is created by a grid of alternating light and dark horizontal and vertical lines. The lines appear to be bent or tilted, even though they are actually straight.

Cafe Wall Illusion



These illusions are usually caused by the way our eyes process visual information and the way the brain interprets it. They can also be caused by the interaction of different visual elements, such as lines and angles, in the image. They are often used in research on visual perception and the neural basis of perception.


Discovery of the Illusory Motion

It is not clear who first discovered illusory motion. Some credit Aristotle in approximately 350 BC.

But these type of illusions have been observed and studied by various researchers over time, and many studies have contributed to the understanding of the phenomenon.

For example, peripheral drift illusions have been observed since the early 20th century and have been studied by various researchers in the field of visual perception, including scientists, psychologists, and neuroscientists.

Some of the early studies on peripheral drift illusions were conducted by the German physiologist Ernst Mach in the late 19th century, and later by the German psychologist Max Wertheimer in the early 20th century.

In the 20th century, several scientists and researchers have made significant contributions to the understanding of peripheral drift illusions and the underlying neural mechanisms, such as the American psychologist J.J. Gibson, the American neuroscientist David Hubel, and the British neuroscientist Melvyn Goodale.


References and Resources

Check out our complete list of illusions and these cool Black and White Illusory motion images.

Motion Aftereffect

Motion-Aftereffect2

The Motion Aftereffect (also known as the Waterfall Illusion) is a visual illusion experienced after viewing a moving visual stimulus, and then fixating on a stationary stimulus. The stationary stimulus appears to move in the opposite direction to the original stimulus.

For example, fixate on the moving image below for several seconds, then shift you gaze to another surface like a plain wall. You should still be able to see the motion on the static surface.

Motion-Aftereffect
Focus on the image for several seconds, then shift your gaze to another surface, you should experience the motion aftereffect

Table of Contents


How does the Motion Aftereffect work?

The motion aftereffect (MAE) is a visual illusion that occurs when one looks at a moving visual stimulus for an extended period of time, and then looks at a still object. The still object will appear to be moving in the opposite direction of the original stimulus. T

his effect is thought to occur because neurons in the visual system become adapted to the motion of the initial stimulus, and then continue to fire as if the motion were still present even when the stimulus is removed.

This causes the perceived motion of the still object.

MAE can occur with various type of motion such as rotation, translation, expansion and contraction.

Versions of the Motion Aftereffect

The following are some other examples of the Waterfall Illusion

Motion Aftereffect
Focus on the image for several seconds, then shift your gaze to another surface, you should experience the motion aftereffect



Waterfall Illusion
Waterfall Illusion
If you focus on the falling water for several seconds, then shift your gaze to a still object, that object will appear to shift upward in the opposite direction of the waterfall




Illusions like the Motion Aftereffect

The following are some illusions that are related to Motion Aftereffect

Motion-induced blindness (MIB) is an optical illusion that occurs when a stationary pattern or image is presented in the presence of a moving pattern or image. The stationary pattern or image appears to disappear or fade, even though it is still present, this phenomenon is called motion-induced blindness.

Motion-Induced-Blindness-Spinning-Table
Focus on the in the center of the table and the different objects disappear and reappear.


Motion-Induced-Blindness-spinning-squares-blue-dot-yellow-dot
Focus on the center dot and and the other dots disappear and reappear

Troxler’s fading, also known as Troxler’s effect, is a phenomenon in which a stationary visual stimulus eventually disappears from perception, even though it is still present in the visual field.

This occurs because the human visual system adapts to constant stimuli and eventually stops responding to them.

Lilac-Chaser_Troxlers Fading
From Wikimedia Commons
After staring at the cross for several seconds, the dots fade away


Troxler-Fading
From Wikimedia Commons
After staring at the cross for several seconds, colors fade away


Toxler-Fading-Blue-Circle-Red-Dot
From Wikimedia Commons
After staring at the dot for several seconds, the colored ring fades away


The Phi phenomenon is the illusion of movement created by the rapid succession of static images or light sources.

It is the perceptual phenomenon that explains how the human brain perceives motion when presented with a sequence of still images or light sources that are displayed in rapid succession.

Magni-phi-phenomonon.
From Wikimedia Commons



The Rotating Snakes is a peripheral drift illusion that consists of a grid of shapes, with some of them appearing to be rotating or undulating. The illusion is created by the interaction of the shapes with the neural processing of the visual system.

Rotating Snakes Autokinetic effect


The Moiré pattern illusion: This illusion is created by superimposing two similar patterns on top of each other, such as a grid of lines or circles. The resulting pattern appears to be moving or changing.

Moiré_pattern
From Wikimedia Commons

The Scintillating Grid Illusion, in which a grid of black and white squares appears to pulsate or “breathe” when viewed from the periphery of the image.

Simultaneous Contrast Illusion



The Hermann Grid Illusion, in which the intersections of a white grid on a black background appear to be gray, even though they are actually the same color as the background.

Hermann-Grid Illusion


The Zöllner Illusion, in which parallel lines appear to be tilted or bent when intersected by diagonal lines.

Zöllner illusion


The Café Wall Illusion is a visual illusion that is created by a grid of alternating light and dark horizontal and vertical lines. The lines appear to be bent or tilted, even though they are actually straight.

Cafe Wall Illusion




Discovery of the Motion Aftereffect

Some believe that The Motion Aftereffect effect was first observed and noted by Aristotle in approximately 350 BC.

More recently, the motion aftereffect was described by German physicist and physician Johann Christoph Friedrich von Schiller in 1812.

He observed that after looking at a rotating wheel for a period of time, stationary objects appeared to rotate in the opposite direction. He called this phenomenon the “spinning wheel illusion.”

However, the phenomenon was independently discovered by several other researchers in the 19th century including Peter Mark Roget and Charles Wheatstone.

References and Resources

Check out our complete list of illusions.

Sign Up to Have Your Mind Blown

Waterfall Illusion

Waterfall Illusion

The Waterfall Illusion (also known as the Motion Aftereffect) a visual illusion experienced after viewing a moving visual stimulus, and then fixating a stationary stimulus. The stationary stimulus appears to move in the opposite direction to the original stimulus.

For example, with a waterfall, after fixating on the falling water for several seconds, when one shifts their gaze to the surrounding rocks, they will appear to move up briefly in the opposite direction of the waterfall

Waterfall Illusion
Waterfall Illusion
If you focus on the falling water for several seconds, then shift your gaze to a still object, that object will appear to shift upward in the opposite direction of the waterfall

Table of Contents


How does the Waterfall Illusion work?

The waterfall illusion is a visual illusion that occurs when a person looks at a waterfall or a rapidly flowing stream.

This illusion is created by the persistence of vision, which occurs when the image of the moving water is retained in the retina for a short period of time after the stimulus is removed.

The brain interprets this as if the water is still moving, and it results in the stationary image to appear to move.

The illusion can also be observed in other types of flowing fluids such as lava, and in moving visual patterns like scrolling text or a zig-zag pattern.

Versions of the Waterfall Illusion

The following are some other examples of the Waterfall Illusion

Motion Aftereffect
Focus on the image for several seconds, then shift your gaze to another surface, you should experience the motion aftereffect



Motion-Aftereffect
Focus on the image for several seconds, then shift your gaze to another surface, you should experience the motion aftereffect




Illusions like the Waterfall Illusion

The following are some illusions that are related to Waterfall Illusion

Motion-induced blindness (MIB) is an optical illusion that occurs when a stationary pattern or image is presented in the presence of a moving pattern or image. The stationary pattern or image appears to disappear or fade, even though it is still present, this phenomenon is called motion-induced blindness.

Motion-Induced-Blindness-Spinning-Table
Focus on the in the center of the table and the different objects disappear and reappear.


Motion-Induced-Blindness-spinning-squares-blue-dot-yellow-dot
Focus on the center dot and and the other dots disappear and reappear

Troxler’s fading, also known as Troxler’s effect, is a phenomenon in which a stationary visual stimulus eventually disappears from perception, even though it is still present in the visual field.

This occurs because the human visual system adapts to constant stimuli and eventually stops responding to them.

Lilac-Chaser_Troxlers Fading
From Wikimedia Commons
After staring at the cross for several seconds, the dots fade away


Troxler-Fading
From Wikimedia Commons
After staring at the cross for several seconds, colors fade away


Toxler-Fading-Blue-Circle-Red-Dot
From Wikimedia Commons
After staring at the dot for several seconds, the colored ring fades away


The Phi phenomenon is the illusion of movement created by the rapid succession of static images or light sources.

It is the perceptual phenomenon that explains how the human brain perceives motion when presented with a sequence of still images or light sources that are displayed in rapid succession.

Magni-phi-phenomonon.
From Wikimedia Commons



The Rotating Snakes is a peripheral drift illusion that consists of a grid of shapes, with some of them appearing to be rotating or undulating. The illusion is created by the interaction of the shapes with the neural processing of the visual system.

Rotating Snakes Autokinetic effect


The Moiré pattern illusion: This illusion is created by superimposing two similar patterns on top of each other, such as a grid of lines or circles. The resulting pattern appears to be moving or changing.

Moiré_pattern
From Wikimedia Commons

The Scintillating Grid Illusion, in which a grid of black and white squares appears to pulsate or “breathe” when viewed from the periphery of the image.

Simultaneous Contrast Illusion



The Hermann Grid Illusion, in which the intersections of a white grid on a black background appear to be gray, even though they are actually the same color as the background.

Hermann-Grid Illusion


The Zöllner Illusion, in which parallel lines appear to be tilted or bent when intersected by diagonal lines.

Zöllner illusion


The Café Wall Illusion is a visual illusion that is created by a grid of alternating light and dark horizontal and vertical lines. The lines appear to be bent or tilted, even though they are actually straight.

Cafe Wall Illusion




Discovery of the Waterfall Illusion

Some believe that the Waterfall effect (or the Motion Aftereffect effect) was first observed and noted by Aristotle in approximately 350 BC.

More recently, the effect was described by German physicist and physician Johann Christoph Friedrich von Schiller in 1812.

He observed that after looking at a rotating wheel for a period of time, stationary objects appeared to rotate in the opposite direction. He called this phenomenon the “spinning wheel illusion.”

However, the phenomenon was independently discovered by several other researchers in the 19th century including Peter Mark Roget and Charles Wheatstone.

References and Resources

Check out our complete list of illusions.

Sign Up to Have Your Mind Blown

Primrose Field

Primrose-Field-by-Kitaoka-Akiyoshi

Primrose Field by Kitaoka AkiyoshiIn is a peripheral drift illusion where the image or pattern appears to move or drift, even though it is actually stationary. This movement is caused by the brain’s attempt to interpret the image or pattern, which is often complex or ambiguous. The movement can be in any direction, such as horizontally, vertically, or diagonally.

Peripheral drift illusions are interesting to study because they can reveal how the visual system processes information and can help us understand the underlying neural mechanisms of visual perception.


Primrose-Field-by-Kitaoka-Akiyoshi
Primrose Field


Table of Contents


How do Peripheral Drift Illusions like Primrose Field work?

Peripheral drift illusions refer to a group of optical illusions where an object or pattern appears to be moving even though it is stationary. These illusions are often characterized by a perceived movement in the peripheral vision, hence the name.

Peripheral drift illusions work by exploiting the way the visual system processes information from the peripheral vision. Our eyes have a higher density of receptors, called rods, in the peripheral vision than in the central vision, and these receptors are more sensitive to movement. The peripheral vision also has a lower resolution and is less sensitive to details than the central vision.

Because of these characteristics, the visual system tends to perceive movement in the peripheral vision more easily than in the central vision. In a peripheral drift illusion, the visual elements of the illusion, such as lines or angles, are arranged in such a way that they create the illusion of movement in the peripheral vision.

Another mechanism that can cause peripheral drift illusions is the way that the brain interprets visual information. The brain uses context and prior experience to make sense of visual information, and this can lead to perceptual errors. For example, in the café wall illusion, the brain interprets the angled lines as the edges of a 3D object, which creates the illusion of movement.

In summary, peripheral drift illusions exploit the characteristics of the peripheral vision, such as sensitivity to movement and lower resolution, and the way the brain interprets visual information to create the illusion of movement in stationary images.

Versions of Peripheral Drift Illusions like Primrose Field

The following are some other examples of peripheral drift illusions


Peripheral_drift_illusion_like-Primrose-Field


Peripheral_drift_illusion_like-Primrose-Field-by-Kitaoka-Akiyoshi


Peripheral_drift_illusion_like-Primrose-Field2






Cafe Wall Variant with Peripheral drift
From Wikimedia Commons


Rotating Snakes Autokinetic effect
From Wikimedia Commons



Peripheral drift illusion
From Wikimedia Commons



peripheral-drift-illusion-giving-a-throbbing-effect
From Wikimedia Commons



Primrose_field_peripheral_drift_illusion
From Wikimedia Commons


Peripheral_drift_illusion_blue-and-orange-wormhole


Illusions like the Primrose Field Peripheral Drift Illusion

Peripheral drift illusions refer to a group of optical illusions where an object or pattern appears to be moving even though it is stationary. These illusions are often characterized by a perceived movement in the peripheral vision, hence the name.

The following are some illusions related to Peripheral Drift Illusions

The rotating snakes is a peripheral drift illusion that consists of a grid of shapes, with some of them appearing to be rotating or undulating. The illusion is created by the interaction of the shapes with the neural processing of the visual system.

Rotating Snakes Autokinetic effect
A Version of Rotating Snakes


The Moiré pattern illusion: This illusion is created by superimposing two similar patterns on top of each other, such as a grid of lines or circles. The resulting pattern appears to be moving or changing.


Moiré_pattern
From Wikimedia Commons


The Scintillating Grid Illusion, in which a grid of black and white squares appears to pulsate or “breathe” when viewed from the periphery of the image.

Simultaneous Contrast Illusion



The Hermann Grid Illusion, in which the intersections of a white grid on a black background appear to be gray, even though they are actually the same color as the background.

Hermann-Grid Illusion


The Zöllner Illusion, in which parallel lines appear to be tilted or bent when intersected by diagonal lines.

Zöllner illusion


The Fraser Spiral Illusion, in which a pattern of short, curved lines appears to form a spiral.

Fraser-spiral-illusion.




The Café Wall Illusion is a visual illusion that is created by a grid of alternating light and dark horizontal and vertical lines. The lines appear to be bent or tilted, even though they are actually straight.

Cafe Wall Illusion



These illusions are usually caused by the way our eyes process visual information and the way the brain interprets it. They can also be caused by the interaction of different visual elements, such as lines and angles, in the image. They are often used in research on visual perception and the neural basis of perception.


Discovery of the Peripheral Drift Illusions

It is not clear who first discovered peripheral drift illusions. These type of illusions have been observed and studied by various researchers over time, and many studies have contributed to the understanding of the phenomenon.

Peripheral drift illusions have been observed since the early 20th century and have been studied by various researchers in the field of visual perception, including scientists, psychologists, and neuroscientists.

Some of the early studies on peripheral drift illusions were conducted by the German physiologist Ernst Mach in the late 19th century, and later by the German psychologist Max Wertheimer in the early 20th century.

In the 20th century, several scientists and researchers have made significant contributions to the understanding of peripheral drift illusions and the underlying neural mechanisms, such as the American psychologist J.J. Gibson, the American neuroscientist David Hubel, and the British neuroscientist Melvyn Goodale.

It is likely that peripheral drift illusions were discovered by multiple individuals independently


References and Resources

Check out our complete list of illusions.

Sign Up to Have Your Mind Blown

Motion Induced Blindness

Motion Induced Blindness

Motion-induced blindness (MIB) is an optical illusion that occurs when a stationary pattern or image is presented in the presence of a moving pattern or image. The stationary pattern or image appears to disappear or fade, even though it is still present, this phenomenon is called motion-induced blindness.

Motion Induced Blindness
From Wikimedia Commons
After focusing on the green dot for several seconds the yellow dots disappear

Table of Contents


How does Motion Induced Blindness work?

Motion-induced blindness (MIB) is an optical illusion that occurs when a stationary pattern or image is presented in the presence of a moving pattern or image. The stationary pattern or image appears to disappear or fade, even though it is still present, this phenomenon is called motion-induced blindness.

This illusion occurs because the brain is more sensitive to movement and is more likely to pay attention to the moving pattern or image, rather than the stationary pattern or image. The brain can become so focused on the moving pattern or image that it “filters out” or “ignores” the stationary pattern or image. This can cause the stationary pattern or image to disappear or fade from perception, even though it is still present.

MIB has been studied extensively, and several theories have been proposed to explain the underlying neural mechanisms, such as the attentional blink theory, the competition between motion signals and static signals theory, or the adaptation theory.

The phenomenon of MIB has been found to have some applications in fields such as cognitive psychology, visual perception and neuropsychology, as well as in some practical fields such as aviation, transportation, and computer science.

Versions of the Motion Induced Blindness

The following are some other examples of the Motion Induced Blindness

Motion-Induced-Blindness-Spinning-Table
Focus on the in the center of the table and the different objects disappear and reappear.




Motion-Induced-Blindness-spinning-squares-blue-dot-yellow-dot
Focus on the center dot and and the other dots disappear and reappear




Illusions like Motion Induced Blindness

The following are some illusions that are related to Motion Induced Blindness

Troxler’s fading, also known as Troxler’s effect, is a phenomenon in which a stationary visual stimulus eventually disappears from perception, even though it is still present in the visual field.

This occurs because the human visual system adapts to constant stimuli and eventually stops responding to them.

Lilac-Chaser_Troxlers Fading
From Wikimedia Commons
After staring at the cross for several seconds, the dots fade away


Troxler-Fading
From Wikimedia Commons
After staring at the cross for several seconds, colors fade away


Toxler-Fading-Blue-Circle-Red-Dot
From Wikimedia Commons
After staring at the dot for several seconds, the colored ring fades away


The Phi phenomenon is the illusion of movement created by the rapid succession of static images or light sources.

It is the perceptual phenomenon that explains how the human brain perceives motion when presented with a sequence of still images or light sources that are displayed in rapid succession.

Magni-phi-phenomonon.
From Wikimedia Commons



The Rotating Snakes is a peripheral drift illusion that consists of a grid of shapes, with some of them appearing to be rotating or undulating. The illusion is created by the interaction of the shapes with the neural processing of the visual system.

Rotating Snakes Autokinetic effect


The Moiré pattern illusion: This illusion is created by superimposing two similar patterns on top of each other, such as a grid of lines or circles. The resulting pattern appears to be moving or changing.

Moiré_pattern
From Wikimedia Commons

The Scintillating Grid Illusion, in which a grid of black and white squares appears to pulsate or “breathe” when viewed from the periphery of the image.

Simultaneous Contrast Illusion



The Hermann Grid Illusion, in which the intersections of a white grid on a black background appear to be gray, even though they are actually the same color as the background.

Hermann-Grid Illusion


The Zöllner Illusion, in which parallel lines appear to be tilted or bent when intersected by diagonal lines.

Zöllner illusion


The Café Wall Illusion is a visual illusion that is created by a grid of alternating light and dark horizontal and vertical lines. The lines appear to be bent or tilted, even though they are actually straight.

Cafe Wall Illusion




Discovery of Motion Induced Blindness

Motion-induced blindness was originally discovered in 1965 by Grindley and Townsend

It was later popularized following work by by Ramachandran and Gregory in 1991.

References and Resources

Check out our complete list of illusions.

Sign Up to Have Your Mind Blown

Peripheral Drift Illusions

Peripheral drift illusion jelly bean

In peripheral drift illusions, the image or pattern appears to move or drift, even though it is actually stationary. This movement is caused by the brain’s attempt to interpret the image or pattern, which is often complex or ambiguous. The movement can be in any direction, such as horizontally, vertically, or diagonally.

Peripheral drift illusions are interesting to study because they can reveal how the visual system processes information and can help us understand the underlying neural mechanisms of visual perception.


Peripheral drift illusion jelly bean
From Wikimedia Commons


Table of Contents


How do Peripheral Drift Illusions work?

Peripheral drift illusions refer to a group of optical illusions where an object or pattern appears to be moving even though it is stationary. These illusions are often characterized by a perceived movement in the peripheral vision, hence the name.

Peripheral drift illusions work by exploiting the way the visual system processes information from the peripheral vision. Our eyes have a higher density of receptors, called rods, in the peripheral vision than in the central vision, and these receptors are more sensitive to movement. The peripheral vision also has a lower resolution and is less sensitive to details than the central vision.

Because of these characteristics, the visual system tends to perceive movement in the peripheral vision more easily than in the central vision. In a peripheral drift illusion, the visual elements of the illusion, such as lines or angles, are arranged in such a way that they create the illusion of movement in the peripheral vision.

Another mechanism that can cause peripheral drift illusions is the way that the brain interprets visual information. The brain uses context and prior experience to make sense of visual information, and this can lead to perceptual errors. For example, in the café wall illusion, the brain interprets the angled lines as the edges of a 3D object, which creates the illusion of movement.

In summary, peripheral drift illusions exploit the characteristics of the peripheral vision, such as sensitivity to movement and lower resolution, and the way the brain interprets visual information to create the illusion of movement in stationary images.

Versions of Peripheral Drift Illusions

The following are some other examples of peripheral drift illusions




Cafe Wall Variant with Peripheral drift
From Wikimedia Commons


Rotating Snakes Autokinetic effect
From Wikimedia Commons



Peripheral drift illusion
From Wikimedia Commons



peripheral-drift-illusion-giving-a-throbbing-effect
From Wikimedia Commons



Primrose_field_peripheral_drift_illusion
From Wikimedia Commons


Peripheral_drift_illusion_blue-and-orange-wormhole


Illusions like the Peripheral Drift Illusions

Peripheral drift illusions refer to a group of optical illusions where an object or pattern appears to be moving even though it is stationary. These illusions are often characterized by a perceived movement in the peripheral vision, hence the name.

The following are some illusions related to Peripheral Drift Illusions

The rotating snakes is a peripheral drift illusion that consists of a grid of shapes, with some of them appearing to be rotating or undulating. The illusion is created by the interaction of the shapes with the neural processing of the visual system.

Rotating Snakes Autokinetic effect
A Version of Rotating Snakes


The Moiré pattern illusion: This illusion is created by superimposing two similar patterns on top of each other, such as a grid of lines or circles. The resulting pattern appears to be moving or changing.


Moiré_pattern
From Wikimedia Commons


The Scintillating Grid Illusion, in which a grid of black and white squares appears to pulsate or “breathe” when viewed from the periphery of the image.

Simultaneous Contrast Illusion



The Hermann Grid Illusion, in which the intersections of a white grid on a black background appear to be gray, even though they are actually the same color as the background.

Hermann-Grid Illusion


The Zöllner Illusion, in which parallel lines appear to be tilted or bent when intersected by diagonal lines.

Zöllner illusion


The Fraser Spiral Illusion, in which a pattern of short, curved lines appears to form a spiral.

Fraser-spiral-illusion.




The Café Wall Illusion is a visual illusion that is created by a grid of alternating light and dark horizontal and vertical lines. The lines appear to be bent or tilted, even though they are actually straight.

Cafe Wall Illusion



These illusions are usually caused by the way our eyes process visual information and the way the brain interprets it. They can also be caused by the interaction of different visual elements, such as lines and angles, in the image. They are often used in research on visual perception and the neural basis of perception.


Discovery of the Peripheral Drift Illusions

It is not clear who first discovered peripheral drift illusions. These type of illusions have been observed and studied by various researchers over time, and many studies have contributed to the understanding of the phenomenon.

Peripheral drift illusions have been observed since the early 20th century and have been studied by various researchers in the field of visual perception, including scientists, psychologists, and neuroscientists.

Some of the early studies on peripheral drift illusions were conducted by the German physiologist Ernst Mach in the late 19th century, and later by the German psychologist Max Wertheimer in the early 20th century.

In the 20th century, several scientists and researchers have made significant contributions to the understanding of peripheral drift illusions and the underlying neural mechanisms, such as the American psychologist J.J. Gibson, the American neuroscientist David Hubel, and the British neuroscientist Melvyn Goodale.

It is likely that peripheral drift illusions were discovered by multiple individuals independently


References and Resources

Check out our complete list of illusions and this cool purple peripheral drift illusion.