Frontier of Applied Illusionology | From psychology to real life: Envisaging the practical application of visual illusions

Developing basic research on visual illusions into real-life applications

Visual illusions are visual perceptions of a target object that deviate from the true characteristics of the object, where the brain perceives the object differently to the state in which it actually exists. The use of computers has brought about remarkable progress in the past 20 years.

The scope of visual illusion research is extremely diverse, ranging from studies of visual illusion of shape (geometrical illusion) to those of color, brightness, completion, and depth. The vast body of knowledge thus accumulated has the potential for application in diverse fields, including medicine, welfare, architecture, transportation, and environmental design.

Diverse applications of visual illusion: From the early detection of glaucoma to traffic jam prevention

Some of our current research projects are moving towards practical application. One such project examines extinction illusion. There is an area on the retina, known as the blind spot, which has no stimulation of light due to penetration of optic nerves. The brain compensates for the lack of visual perception in this area through a process known as visual completion; this is kind of extinction illusion. The blind spot region is not simply rendered invisible, but is patched up to match the surrounding pattern through a phenomenon known as "filling-in". We are hoping to apply the phenomena associated with extinction illusion towards the development of an early discovery technique for glaucoma.

Another project is developing a method in which the visual illusion of a vertical gradient, in which an uphill gradient is perceived as a downhill gradient, or vice versa, when a road is viewed head-on, is used to develop traffic jam countermeasures. Sag sections of roads, where the gradient changes from downhill to uphill, are susceptible to traffic jams. This project works in partnership with experts in traffic jam and relevant authorities to explore methods for counteracting the visual illusion of vertical gradient that occurs in sag sections.

We are also working towards the application of color illusion in the fields of barrier-free color vision and universal design, such as design that calls attention to crucial content and the use of colors also visible to those with color anomalous vision.

Stationary image appearing to move due to differences in luminance contrast

We also have a strong body of results from numerous other basic research projects into other visual illusion types. One of these is the anomalous motion illusion shown in a stationary image. We studied the mechanism behind the Fraser-Wilcox illusion, reporting that the degree of visual illusion increases when the regions with differing luminance are arranged in a sequence of dark, moderately dark, bright, moderately bright, and dark. An artwork "Rotating Snakes", an illusion utilizing this principle, proved popular.

We aim to continue to shed light on the mechanisms behind various visual illusions, and to continue to discover illusions that affect our living environment. We will apply our findings towards improving the living environment and contributing to medicine and industry.


Visual illusion, Illusion, Color perception, Spatial perception, Visual completion

Professor Akiyoshi Kitaoka

Professor Akiyoshi Kitaoka

College of Letters
03/1984 University of Tsukuba Second Cluster of College Biology Graduated
03/1991 University of Tsukuba "Graduate School, Division of Psychology" Doctor course Completed
Membership of Academic Societies
Japanese Psychological Association, Japanese Psychonomic Society

Ritsumeikan University Research Database : Akiyoshi Kitaoka
Akiyoshi's illusion pages
Frontier of Applied Illusionology (Japanese Page)

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