Visual Illusions Module Map

Purpose  To demonstrate and explain four well-known visual illusions.

Summary  Students test their sensitivity to the Müller-Lyer, Ponzo, Horizontal-Vertical, and Poggendorf illusions by adjusting the length of a line in order to match the apparent length or position of another. For each illusion, students go through 4 trials without feedback, and then see a graph of their results. The graph is interpreted, and an explanation of the illusion is provided. Next students repeat the 4 trials, but this time the correct length or position of the adjustment line is displayed after each trial. Students can test whether knowing why the illusions occur will help them overcome the effect of the illusions.

Introduction
Müller-Lyer illusion
Ponzo illusion
Horizontal-Vertical illusion
Poggendorf illusion
 		Summary
References


Click here to open the worksheet that accompanies this module. (Requires Adobe Acrobat Reader. Click here to get Adobe Acrobat Reader. Internet connection required to download plug-in.)