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Published on: March 18, 2019
Processing convexity and concavity along a 2-D contour: figure-ground, structural shape, and attention
Marco Bertamini1, Johan Wagemans
1Department of Experimental Psychology, Eleanor Rathbone Building, University of Liverpool, Liverpool L69 7ZA, UK. M.Bertamini@liv.ac.uk
Psychonomic Bulletin & Review
|November 29, 2012
Summary
Convexity and concavity in visual perception significantly aid in distinguishing objects from their background and in understanding object parts. However, their precise role in depth perception and attention allocation requires further investigation.
Area of Science:
- Vision Science
- Cognitive Psychology
- Neuroscience
Background:
- Convexity and concavity are fundamental geometric properties of contours in images.
- These properties provide crucial information for inferring solid shape and object structure.
- Historical interest in vision science highlights the importance of these features in visual processing.
Purpose of the Study:
- To review and analyze evidence on the role of convexity and concavity in visual perception.
- To examine the impact of convexity on figure-ground separation, part structure, and attention.
- To clarify the consensus and discrepancies in interpreting convexity's contribution to visual tasks.
Main Methods:
- Comprehensive review of existing literature.
- Analysis of behavioral, neurophysiological, imaging, and developmental studies.
- Focus on 2-D contour properties and their link to 3-D perception.
Main Results:
- Strong evidence supports the role of convexity in figure-ground organization.
- Convexity information is important for parsing visual scenes into object parts.
- Disagreement exists regarding convexity's contribution to metric depth and automatic attention guidance.
Conclusions:
- Convexity plays a well-established role in fundamental visual organization tasks like figure-ground separation and object parsing.
- Specific claims about convexity's influence on depth perception and attentional mechanisms remain debated and require more robust evidence.
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