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Updated: May 13, 2026
06:14
A Method for Investigating Change Blindness in Pigeons (Columba Livia)
Published on: September 7, 2018
No evidence for an item limit in change detection
Shaiyan Keshvari1, Ronald van den Berg, Wei Ji Ma
1Department of Neuroscience, Baylor College of Medicine, Houston, Texas, United States of America.
Plos Computational Biology
|March 8, 2013
Summary
Working memory capacity is not limited by a fixed number of items. Instead, performance depends on the precision of stimulus encoding, challenging item-limit models.
Area of Science:
- Cognitive psychology
- Neuroscience
Background:
- The change detection paradigm traditionally supports item-limit models of working memory capacity.
- Recent research suggests working memory may be limited by encoding precision (continuous-resource models).
Purpose of the Study:
- To investigate whether working memory is limited by item number or encoding precision.
- To rigorously compare item-limit and continuous-resource models using change detection.
Main Methods:
- Conducted two change detection experiments using orientation and color stimuli.
- Included a wide range of change magnitudes, including small changes, to assess encoding precision.
- Compared the performance against five different theoretical models.
Main Results:
- Found no evidence supporting an item limit in working memory.
- Human change detection performance was best explained by a continuous-resource model.
- This model incorporates variable encoding precision across items and trials.
Conclusions:
- Working memory capacity is better described by continuous-resource models than item-limit models.
- Findings challenge the theoretical underpinnings of many neural studies on working memory capacity.
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