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Creating Objects and Object Categories for Studying Perception and Perceptual Learning
Published on: November 2, 2012
Dividing attention between the color and the shape of objects
1Centre de Recherche en Psychologie Cognitive CNRS-CNRC, Marseille, France. ambonnel@socrates.berkeley.edu
Perception & Psychophysics
|March 21, 1998
Summary
Dividing attention between stimulus features like color and shape can be efficient when features share the same object. However, performance declines when these features are spatially separated, suggesting attention is limited by object and space.
Area of Science:
- Cognitive Psychology
- Neuroscience
Background:
- Dual-task experiments often vary attentional priority between spatially distinct objects.
- Limited research exists on dividing attention between non-spatial stimulus attributes.
Purpose of the Study:
- To investigate how attention is divided between stimulus attributes (color and shape) when they are presented together or separately.
- To test the predictions of object and space-based models of attention.
Main Methods:
- Experiment 1: Observers identified color and shape of a single letter (spatially coincident).
- Experiment 2: Observers identified color and shape of letters presented in different locations (spatially distinct).
- Trial-by-trial analysis correlated performance on color and shape identification.
Main Results:
- When color and shape were on the same object, dual-task accuracy was similar to single-task, with high positive correlation between feature identification.
- When color and shape were spatially separated, dual-task performance was significantly worse than single-task, with high negative correlation.
- Results suggest that attention often processes only one dimension within a trial.
Conclusions:
- Attention can be efficiently divided between features of the same object.
- Dividing attention between spatially separated features incurs a significant performance cost.
- Findings support both object-based and space-based theories of attentional selection.
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