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Creating Virtual-hand and Virtual-face Illusions to Investigate Self-representation
Published on: March 1, 2017
A new "tilt" illusion reveals the relation between border ownership and border binding
1Dipartimento di Psicologia Generale, Università degli Studi di Padova, Padova, Italy. sergio.roncato@unipd.it
Journal of Vision
|September 19, 2009
Summary
The seesaw illusion demonstrates that contrast polarity is crucial for visual perception, influencing how the brain binds edges. This finding highlights that figure/ground organization precedes edge binding in visual processing.
Area of Science:
- Visual Perception
- Computational Neuroscience
- Image Processing
Background:
- "Association field" models explain contour detection by linking neighboring elements.
- Previous work suggested these models account for perceptual binding of luminance edges and illusory tilt.
- The seesaw illusion involves perceived inversion of illusory curvature with background luminance changes.
Purpose of the Study:
- To investigate the role of contrast polarity in the "association field" model.
- To explain the newly developed seesaw illusion.
- To confirm that figure/ground organization precedes perceptual binding of edges.
Main Methods:
- Developed a new version of the tilt illusion, the seesaw illusion.
- Tested the illusion with tile-edge segmentation of alternating black-white segments.
- Varied edge distance, segment length, and background luminance.
Main Results:
- The seesaw illusion requires incorporating contrast polarity into the "association field" concept.
- The illusion persists up to 16 arcmin edge distance despite conflicting local tilts.
- Specific luminance conditions and segment lengths influence edge binding and perceptual assimilation.
Conclusions:
- Contrast polarity is essential for understanding the "association field" and the seesaw illusion.
- Figure/ground organization demonstrably precedes perceptual binding of edges.
- Findings reinforce the significance of border ownership in visual processing.
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