The crater illusion is a visual illusion that make it seem that craters appear to be raised, when if fact, they are indented.
Table of Contents
- How does the Crater Illusion work?
- Versions of the Crater Illusion
- Illusions like the Crater Illusion
- Discovery of the Crater Illusion
- References and Resources
How does the Crater Illusion work?
The illusion is created by the brain’s interpretation of depth and perspective. The circles appear to be raised or indented because the brain interprets the circles that are farther away as smaller and those that are closer as larger. This creates the illusion of depth and the appearance of a series of shallow or deep depressions.
The illusion is a variation of the well-known “Ebbinghaus illusion” which is based on the same principle of relative size perception, but it’s composed by circles instead of circles and circles and it’s called the “crater illusion” because the circles resemble the shape of craters.
It is important to note that the illusion is purely visual, the circles themselves are actually the same size, and there is no actual depth or depression.
Versions of the Crater Illusion
The following is another example of the Crater Illusion:
Illusions like the Crater Illusion
The crater illusion is a type of visual illusion known as a size-distance illusion. Size-distance illusions involve the perception of objects that appear to be different sizes based on their distance from the viewer. The crater illusion specifically is a variation of the well-known “Ebbinghaus illusion” which is a size-distance illusion that occurs when two circles of the same size are surrounded by circles of different sizes.
Size-distance illusions are caused by the way our brains perceive and interpret visual information. Our brains use various cues, such as relative size, texture, and lighting to judge the distance of objects in our environment. In the case of the crater illusion, the brain interprets the circles that are farther away as smaller and those that are closer as larger, which creates the illusion of depth and the appearance of a series of shallow or deep depressions.
It’s important to note that the illusion is purely visual, the circles themselves are actually the same size, and there is no actual depth or depression.
The Ebbinghaus illusion (also known as Titchener circles) is a perceptual illusion in which the perceived size of a central circle is affected by the size of the surrounding circles. The central circle appears smaller when surrounded by larger circles, and larger when surrounded by smaller circles.
The Delboeuf illusion is similar to the Ebbinghaus illusion, but instead of circles, it uses two concentric circles or rings. The central ring appears larger or smaller depending on the size of the surrounding ring.
The Poggendorff illusion is another size-contrast illusion in which a straight line appears to be bent or angled, due to the presence of intersecting lines or shapes in the background.
The Zöllner illusion is another size-contrast illusion in which a group of diagonal lines appear to be distorted or bent due to the presence of intersecting lines.
The Müller-Lyer illusion is a classic example of size-contrast illusion, in which two lines of equal length appear to be different due to the presence of arrowheads or fins at the end of the lines.
All of these illusions rely on the way the visual system processes relative size information, and they all highlight the complexity and malleability of visual perception.
Discovery of the Crater Illusion
The origins of the crater illusion are not well-documented, but it is considered a variation of the well-known “Ebbinghaus illusion” which was first described by the German psychologist Hermann Ebbinghaus in his 1885 book “Über das Gedächtnis” (On Memory).
He observed that when two circles of the same size are surrounded by circles of different sizes, the central circles appear to be different sizes. This illusion is an example of the size-distance illusion, which occurs when the perception of the size of an object is affected by its distance from the viewer.
It’s important to note that the crater illusion, as a specific variation of the Ebbinghaus illusion, is a well-established phenomenon in the field of psychology and it’s widely studied by researchers in the field of visual perception.
The Ebbinghaus illusion is named after German psychologist Hermann Ebbinghaus, who first described it in the late 19th century. The illusion is thought to be caused by the way the brain processes relative size information in visual scenes.
Hermann Ebbinghaus (1850-1909) was a German psychologist who is best known for his pioneering research on memory and forgetting. He was one of the first researchers to systematically study memory as a psychological process and his work laid the foundation for the field of experimental psychology. Ebbinghaus conducted a series of experiments in which he memorized lists of nonsense syllables and then tested his own memory at various intervals to measure the rate of forgetting.
He also developed the first standardized memory test, called the “memory drum”, which consisted of a rotating drum with lists of words or syllables that could be presented to participants at different intervals. He used these tests to study the effects of different factors, such as repetition and interference, on memory retention.
Ebbinghaus also made significant contributions to the understanding of memory processes, such as the spacing effect, which states that spaced practice is more effective than massed practice in enhancing memory retention.
Ebbinghaus’s work was groundbreaking in the field of psychology and is still widely cited today. The Ebbinghaus illusion, the size-contrast illusion that bears his name, was discovered by him in 1885 but is not as well-known as his memory research.
References and Resources
Check out our complete list of illusions.
