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.
In the image below, the direction of the stairs depends on whether you believe A or B to be the closer wall.
Table of Contents
- How does the Schroeder Stairs Illusion work?
- Versions of the Schroeder Stairs Illusion
- Illusions like the Schroeder Stairs Illusion
- Discovery of the Schroeder Stairs Illusion
- References and Resources
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How does the Schroeder Stairs Illusion work?
The illusion is created by the way the brain interprets the 2-dimensional image of the staircase.
The brain can interpret the image in different ways, as a staircase that is going up or going down depending on how the brain organizes the information.
The illusion works by playing with the viewer’s expectations about the relationship between the lines of the staircase and the viewer’s sense of depth.
The brain uses cues such as perspective, shading, and past experiences to create a 3-dimensional perception of the image.
In the case of Schröder Stairs, the brain can interpret the lines of the staircase as either the front or back of a staircase.
Since there is no clear cue that indicates which interpretation is correct, the brain tends to flip between these two interpretations in a random manner, creating the illusion that the staircase is changing its orientation.
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.
Versions of the Schroeder Stairs Illusion
The following are some alternate versions of the Schroeder Stairs Illusion:
Illusions like the Schroeder Stairs 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.
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.
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.
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.
The impossible cube is an optical illusion that depicts a three-dimensional object that is physically impossible to construct.
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.
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.
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
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.
Discovery of the Schroeder Stairs Illusion
The illusion was named after the German psychologist Hermann Schröder, who first published it in his 1858 book “Untersuchungen zur Lehre vom Lichtsinn” (Investigations into the Theory of Light Sense).
Hermann Schröder was a German psychologist and physiologist who was born in 1838 and died in 1902.
He is best known for his work on visual perception, especially his study of optical illusions.
Schröder was one of the first scientists to systematically study optical illusions and the ways in which the brain interprets visual information. He published a book in 1858 called “Untersuchungen zur Lehre vom Lichtsinn” (Investigations into the Theory of Light Sense) which contains several optical illusions, including the Schröder Staircase, which is named after him.
Schröder also conducted research on other areas of psychology, such as the perception of color and the physiology of the eye.
He was a professor of physiology and neurology at the University of Kiel, and later at the University of Strasbourg.
Schröder was a pioneer in the field of visual perception and his work laid the foundation for the modern study of optical illusions and the brain’s interpretation of visual information.
His work was influential in the development of Gestalt psychology, which is a psychological theory that emphasizes the importance of the whole experience and the context in which it is perceived.
References and Resources
Check out our complete list of illusions.