Related Experiment Videos
When "capacity" changes with set size: Ensemble representations support the detection of across-category changes in
Mark W Schurgin1, Timothy F Brady1
1Department of Psychology, University of California, San Diego, San Diego, CA, USA.
Journal of Vision
|May 7, 2019
Summary
Working memory capacity is not fixed by item count but influenced by object complexity and ensemble representations. These factors, rather than a strict slot limit, better explain performance in memory tasks.
Area of Science:
- Cognitive Psychology
- Neuroscience
Background:
- Debate exists on whether working memory has a fixed item limit or a limited resource.
- Some studies suggest stimulus similarity and ensemble information influence memory performance, challenging fixed-slot models.
Purpose of the Study:
- To investigate the role of ensemble representations in working memory capacity.
- To determine if object complexity and similarity, or a fixed slot limit, better explain memory performance.
Main Methods:
- Experiment 1: Assessed capacity estimates with increasing set sizes (4-12 items) for across-category changes.
- Experiment 2: Manipulated the utility of ensemble information in a change-detection task, controlling for complexity and similarity.
Main Results:
- Capacity estimates increased linearly with set size in Experiment 1, contradicting a fixed capacity.
- Working memory capacity was significantly higher when ensemble information was usable in Experiment 2.
Conclusions:
- Findings challenge the notion of a slot-like, fixed-object constraint on working memory.
- Object complexity and ensemble representations significantly impact working memory performance.