Summary
The Ehrenstein illusion is an optical illusion studied by the German psychologist Walter Ehrenstein (1899 – 1961) in which the sides of a square placed inside a pattern of concentric circles take an apparent curved shape.[1][2]
Original Ehrenstein illusion, where a square appears curved when placed inside of concentric circles
Alternative Ehrenstein illusion, where the ends of the dark segments produce the illusion of circles
The illusion of a bright central disk (above) is destroyed by adding a circle (bottom). The monochromity of the piece further adds to the affect of this square appearing to become curved, a common illusion many associate with the umbrella term of optical illusions.
Sometimes the name "Ehrenstein" is associated with one of the illusory contour figures where the ends of the dark segments produce the illusion of circles.[3][4][5] The apparent figures have the same color as the background, but appear brighter. A similar effect is obtained in the Kanizsa triangle.
ReferencesEdit
| Wikimedia Commons has media related to Ehrenstein illusion. |
- ^ A catalogue of illusions at Ritsumeikan University
- ^ W. Ehrenstein (1925). "Versuche über die Beziehungen zwischen Bewegungs- und Gestaltwahrnehmung" [Experiments on the Relationships Between the Perception of Motion and of Gestalt]. Zeitschrift für Psychologie. 96: 305–352.
- ^ Ehrenstein illusion at Scholarpedia
- ^ W. Ehrenstein (1941). "Über Abwandlungen der L. Hermannschen Helligkeitserscheinung". Zeitschrift für Psychologie. 150: 83–91.
- ^ W. Ehrenstein (1954). Probleme der ganzheitspsychologischen Wahrnehmungslehre. Leipzig: Barth.