Tunnel Illusion

This cool tunnel illusion that creates the illusion of a 3D tunnel or a concave shape that moves slightly despite the fact that the image is completely flat.

If you are interested about how this cool tunnel illusion works, scroll down to readmore about it.

Tunnel Illusion


Table of Contents

What is the Tunnel Illusion?

The tunnel illusion is an optical illusion that creates the illusion of a tunnel or a concave shape when, in fact, the image is completely flat.

The black and white checkerboard pattern is often used to create this illusion. In this version of the illusion, the checkerboard pattern is placed on a flat surface and the pattern is manipulated so that the squares appear to be getting smaller as they get further away from the viewer. This creates the impression of a tunnel or a concave shape that appears to be extending into the distance.

The illusion works because of the way our brains interpret depth cues. As objects get further away, they appear smaller, and our brains use this information to interpret the size and shape of objects in the world. By manipulating the size of the squares in the checkerboard pattern, the illusion tricks our brains into perceiving a depth that isn’t actually there.

How does the Tunnel Illusion Work?

The tunnel illusion works by exploiting our brain’s perception of depth and perspective. When we look at an image that includes converging lines or patterns, our brain naturally interprets those lines as representing depth or distance. In the case of the tunnel illusion, the black and white checkerboard pattern is arranged in such a way that the squares appear to be getting smaller as they recede into the distance. This creates the impression that the image is actually a tunnel or a concave shape, when in reality it is just a flat image.

Our brain relies on many different cues to interpret depth and distance, including binocular disparity (the difference between the images received by our two eyes), motion parallax (the way objects appear to move at different rates when we move our head or eyes), and perspective (the way objects appear smaller when they are further away). In the case of the tunnel illusion, perspective is the key cue that tricks our brain into perceiving depth and distance.

When we look at the tunnel illusion, our brain automatically interprets the converging lines of the checkerboard pattern as representing a tunnel or a concave shape, even though we know intellectually that the image is flat. This is because our brain is wired to interpret certain patterns as representing depth and distance, and the checkerboard pattern used in the illusion is a particularly effective way of exploiting this wiring.

Some Similar Illusions

There are many other optical illusions that are similar to the tunnel illusion, in that they exploit our brain’s perception of depth and distance to create a false sense of three-dimensionality. Here are a few examples:

  1. Ames Room illusion: This illusion creates the impression of a room that is longer or shorter than it actually is. It works by using forced perspective, where one side of the room is closer to the viewer than the other. This makes objects and people in the room appear to be larger or smaller than they actually are.
  2. Ponzo illusion: This illusion creates the impression that two identical lines are different lengths, based on their context. The illusion works by placing the lines in the context of converging lines that suggest depth, which causes our brain to interpret the top line as being further away than the bottom line.
  3. Mueller-Lyer illusion: This illusion creates the impression that two identical lines are different lengths, based on the presence of angled lines at the ends of the lines. The illusion works because our brain interprets the angled lines as indicating perspective, and assumes that the line with the outward-angled lines is further away and therefore longer. The Müller-Lyer illusion was first described by Franz Carl Müller-Lyer in 1889.
  4. Hering illusion: This illusion creates the impression that two parallel lines are curved, based on the presence of converging or diverging lines around them. The illusion works by exploiting our brain’s tendency to interpret certain visual patterns as representing depth and perspective.

These are just a few examples of the many optical illusions that are similar to the tunnel illusion in their use of depth and perspective cues to create a false sense of three-dimensionality.

Discovery of the Tunnel Illusion

The tunnel illusion has been studied by many researchers over the years, and it’s difficult to attribute its discovery to any one person. However, one of the earliest known examples of the tunnel illusion can be found in a 1904 book called “The Psychology of Special and Differential Diagnosis of Malingerers” by Dr. William Hirsch, a German ophthalmologist.

Hirsch included an illustration in his book that featured a black and white checkerboard pattern arranged in a way that created the illusion of a concave tunnel. Although Hirsch did not describe the illusion in detail or conduct any experiments to study it, his illustration is one of the earliest known examples of the tunnel illusion.

Since Hirsch’s time, the tunnel illusion has been studied and discussed by many other researchers, including psychologists, neuroscientists, and vision scientists. It has been used as a tool for understanding how our brains process visual information, and it continues to fascinate and intrigue scientists and laypeople alike.


References and Resources

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