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Non-veridical size perception of expanding and contracting objects
D Whitaker1, P V McGraw, S Pearson
1Department of Optometry, University of Bradford, UK. d.j.whitaker@bradford.ac.uk
This study explores how people perceive the size of objects that are expanding or contracting. The researchers found that when an object's internal texture changes, either through real motion or an illusion called a movement after-effect, people misperceive the object's size. The direction of the size change—whether expansion or contraction—biases the perception. The study also shows that the spatio-temporal features of these changes are consistent across real and illusory conditions. These findings may suggest that texture motion and size perception are linked through shared mechanisms in the visual system.
Area of Science:
- Visual perception research in cognitive psychology
- Spatio-temporal processing in neuroscience
Background:
Prior research has shown that visual perception can be influenced by dynamic changes in stimuli. It was already known that apparent size can shift with motion patterns. However, the specific mechanisms behind size misperception during texture changes remain unclear. This gap motivated a closer examination of how internal texture affects perceived size. No prior work had resolved how illusory texture manipulations interact with size perception. The role of spatio-temporal dynamics in these illusions has not been fully explored. That uncertainty drove the need for controlled experiments on expanding and contracting objects. The current study addresses these unresolved questions in visual perception.
Purpose Of The Study:
The aim of this study is to investigate how changing internal textures affect perceived object size. It focuses on the misperception of size during expansion and contraction. The specific problem involves understanding how texture motion influences perception. The motivation stems from gaps in understanding spatio-temporal processing. The study seeks to clarify whether real or illusory texture changes produce similar effects. It also aims to explore the characteristics of these perceptual shifts. The approach combines real and illusory texture manipulations. The findings may contribute to models of dynamic visual processing.
Main Methods:
The researchers used stimulus sequences involving expanding and contracting objects. They manipulated internal textures to observe size perception changes. A movement after-effect was used to simulate illusory texture motion. Observers were asked to report perceived size differences. The study compared real texture changes with illusory ones. Spatio-temporal features were analyzed for perceptual consistency. The design included controlled variations in texture dynamics. The results were based on observer responses and pattern analysis.
Main Results:
The perceived size of changing objects was biased toward the direction of size change. Expansion or contraction of internal texture altered perceived size significantly. Illusory texture changes produced similar misperceptions as real ones. The movement after-effect replicated the effects of actual texture motion. The results suggest a shared mechanism for real and illusory texture perception. Spatio-temporal characteristics were consistent across conditions. The findings support the idea that texture dynamics influence size perception. The data indicate a strong link between texture motion and perceived size.
Conclusions:
The authors propose that texture motion biases perceived size in the direction of change. They suggest that both real and illusory texture changes share perceptual mechanisms. The findings may suggest broader implications for dynamic visual processing. The study does not claim to resolve all aspects of size perception. The results may suggest a role for spatio-temporal processing in perception. The authors do not assign essentiality to any specific mechanism. The conclusions are limited to the observed effects in the study. The findings may suggest new directions for exploring visual illusions.
Frequently Asked Questions
The study found that perceived object size is biased in the direction of expansion or contraction.
Changes in internal texture, whether real or illusory, influence perceived size similarly.
The movement after-effect simulates texture motion and produces similar size misperceptions.
Spatio-temporal features are consistent across real and illusory texture changes.
Observer responses were used to measure perceived size differences in dynamic conditions.
The authors suggest that texture motion influences size perception through shared mechanisms.