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Updated: Aug 8, 2026
10:41
VisualEyes: A Modular Software System for Oculomotor Experimentation
Published on: March 25, 2011
Occlusion, symmetry, and object-based attention: reply to Saiki (2000)
M Behrmann1, R S Zemel, M C Mozer
1Department of Psychology, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213-3890, USA. behrmann+@cmu.edu
Summary
Object-based attention relies on perceptual organization, not just symmetry. New research shows grouping heuristics like common fate enable attention to amodally completed objects, supporting this view.
Area of Science:
- Cognitive Psychology
- Visual Perception
Background:
- Previous research on object-based attention was critiqued for using stimuli confounded by symmetry.
- The role of perceptual organization in object-based attention requires further elucidation.
Purpose of the Study:
- To re-examine claims regarding amodally completed objects and object-based attention.
- To propose that perceptual organization, utilizing grouping heuristics, underlies object-based attention.
Main Methods:
- Experiments were designed using stimuli that exploit the common fate grouping heuristic.
- Displays were created to test for a single-object advantage with occluded shapes.
Main Results:
- A single-object advantage, characteristic of object-based attention, was observed for amodally completed shapes.
- The results support the role of grouping heuristics in facilitating feature attention within a single object.
Conclusions:
- Perceptual organization, driven by heuristics like common fate, is a key mechanism for object-based attention.
- Amodally completed objects can benefit from object-based attention when organized perceptually.
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