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A Psychophysics Paradigm for the Collection and Analysis of Similarity Judgments
Published on: March 1, 2022
Homogeneity computation: how interitem similarity in visual short-term memory alters recognition
Shivakumar Viswanathan1, Daniel R Perl, Kristina M Visscher
1Department of Psychology, University of California, Santa Barbara, California 93101, USA. shiva@psych.ucsb.edu
Psychonomic Bulletin & Review
|January 19, 2010
Summary
The homogeneity of visual stimuli impacts short-term memory. This study shows that memory performance is adjusted by comparing items, not by how well items are stored.
Area of Science:
- Cognitive Psychology
- Neuroscience
- Visual Perception
Background:
- Short-term memory is affected by stimulus similarity.
- The underlying mechanism of this homogeneity effect is not well understood.
Purpose of the Study:
- To investigate the mechanism behind the homogeneity effect in visual short-term recognition memory.
- To differentiate between encoding/maintenance fidelity and item comparison as explanations.
Main Methods:
- Controlled experiments using Gabor patches as stimuli.
- Assessing recognition memory for spatial frequency.
- Evaluating competing hypotheses for the homogeneity effect.
Main Results:
- Evidence against higher encoding or maintenance fidelity for similar items.
- Support for a trial-by-trial item comparison mechanism.
- A "homogeneity signal" modulates decision criteria.
Conclusions:
- The homogeneity effect in visual memory arises from item comparisons, not storage fidelity.
- A homogeneity signal, computed before probe presentation, adjusts decision criteria.
- Recognition-like processes may apply to stored items, not just probes.
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