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Updated: Jul 16, 2025
09:49
Methods to Explore the Influence of Top-down Visual Processes on Motor Behavior
Published on: April 16, 2014
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Exploring the extent to which shared mechanisms contribute to motion-position illusions
Timothy V Cottier1,2, William Turner1,3,4, Alex O Holcombe5,6
1Melbourne School of Psychological Sciences, the University of Melbourne, Melbourne, Australia.
Journal of Vision
|September 13, 2023
Summary
Most motion-position illusions (MPIs) do not share common mechanisms, despite phenomenological similarities. This study found only two small clusters of MPIs that may share underlying processes, suggesting unique mechanisms for most illusions.
Area of Science:
- Visual perception
- Neuroscience
- Psychophysics
Background:
- Motion-position illusions (MPIs) involve motion signals influencing perceived object location.
- Phenomenological similarities suggest shared mechanisms, but this remains untested.
Purpose of the Study:
- To investigate whether different MPIs share common underlying neural mechanisms.
- To test the assumption of shared mechanisms based on observed illusion magnitudes.
Main Methods:
- 106 participants completed two sessions, experiencing eight different MPIs.
- Individual differences in illusion magnitude were analyzed for within- and between-illusion correlations.
- Exploratory factor analysis was used to identify shared underlying factors.
Main Results:
- Illusion magnitudes were reliable within participants across sessions.
- Two clusters of MPIs showed significant positive correlations: (1) flash-grab, motion-induced position shift, twinkle-goes; (2) Fröhlich, flash-drag.
- Factor analysis supported these clusters, indicating shared factors within each cluster.
Conclusions:
- Contrary to prior assumptions, most MPIs likely rely on unique mechanisms.
- Only specific MPIs, grouped into identified clusters, appear to share underlying processes.
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