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Demystifying the Poggendorff: a start.

Theodore E Parks¹

¹Department of Psychology, University of California at Davis, Davis, CA 95616, USA. mumsown@dcn.org

|March 28, 2009

Summary

This summary is machine-generated.

The Poggendorff illusion, a visual misalignment, is explained by a new theory. This theory incorporates pictorial height-in-scene and illusory diagonal rotation as key contributing factors to the classic pattern.

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Area of Science:

Visual perception
Geometric illusions

Background:

The Poggendorff illusion demonstrates a misalignment in a geometric pattern.
Previous explanations failed to account for the lack of illusion in reduced Poggendorff patterns.

Purpose of the Study:

To explain the Poggendorff illusion in the classic pattern.
To account for the failure of illusory misalignment in reduced patterns.

Main Methods:

Analysis of the classic Poggendorff pattern.
Analysis of a reduced Poggendorff pattern (acute angles only).

Main Results:

Reduced Poggendorff patterns show little to no illusory misalignment.
A novel theory explains the classic pattern's illusion.

Conclusions:

The new theory successfully explains both the presence of the Poggendorff illusion in the classic pattern and its absence in reduced patterns.
Pictorial height-in-scene and illusory rotation-of-the-diagonals are identified as crucial factors.