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Creating Virtual-hand and Virtual-face Illusions to Investigate Self-representation
Published on: March 1, 2017
Perceiving the present and a systematization of illusions.
Mark A Changizi1, Andrew Hsieh, Romi Nijhawan
1Sloan-Swartz Center for Theoretical Neurobiology, California Institute of TechnologyDepartment of Biology, California Institute of TechnologyDepartment of Psychology, University of Sussex.
Cognitive Science
|June 4, 2011
Summary
Visual perception research reveals empirical regularities in illusions. Factors like size and speed influence perceived size, speed, contrast, and distance, supporting the "perceiving the present" hypothesis.
Area of Science:
- Visual Perception
- Psychophysics
- Computational Neuroscience
Background:
- Visual illusions are numerous but lack systematic organization.
- Existing theories struggle to explain the full spectrum of visual illusions.
- Understanding these illusions is key to understanding visual processing.
Purpose of the Study:
- To systematically organize over 50 visual illusions into a structured classification matrix.
- To identify empirical regularities in visual perception across various factors.
- To test the "perceiving the present" hypothesis for visual system function.
Main Methods:
- Categorization of over 50 visual illusions into a 7x4 matrix.
- Analysis of perceptual effects related to size, speed, luminance contrast, distance, eccentricity, vanishing point, and focus of expansion.
- Testing the predictive power of the "perceiving the present" hypothesis.
Main Results:
- Identified 28 distinct classes of visual illusions within the matrix.
- Demonstrated that smaller size, slower speed, greater contrast, farther distance, lower eccentricity, and proximity to the vanishing point/focus of expansion have consistent perceptual effects.
- These factors consistently increase perceived size and speed, while decreasing perceived contrast and distance.
Conclusions:
- A systematic framework for organizing visual illusions has been established.
- Empirical regularities in visual perception were identified and linked to specific stimulus properties.
- The "perceiving the present" hypothesis provides a unifying explanation for these observed regularities, suggesting neural delay compensation mechanisms.
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