Related Experiment Video
Updated: May 16, 2026
09:13
A Real-world What-Where-When Memory Test
Published on: May 16, 2017
Source accuracy data reveal the thresholded nature of human episodic memory
Iain M Harlow1, David I Donaldson
1Neuroinformatics Doctoral Training Centre, University of Edinburgh, Edinburgh, Scotland. imharlow@ucdavis.edu
Psychonomic Bulletin & Review
|November 30, 2012
Summary
Memory recollection operates on a threshold, meaning retrieval either succeeds or fails completely. This study developed a new method to directly measure memory retrieval accuracy, clarifying a key aspect of how we remember past events.
Area of Science:
- Cognitive Psychology
- Neuroscience of Memory
Background:
- Episodic recollection is crucial for conscious memory retrieval.
- The variability in memory recall (vivid vs. difficult) is not fully understood.
- Existing theories propose either a strict recollection threshold or a continuous memory signal.
Purpose of the Study:
- To reconcile competing theories of memory recollection (threshold vs. continuous signal).
- To develop and validate a novel method for directly measuring retrieval accuracy.
- To investigate the fundamental properties of episodic memory retrieval.
Main Methods:
- Development of a novel source memory task.
- Direct measurement of retrieval accuracy, bypassing subjective introspection.
- Experimental manipulation to assess recollection success or failure.
Main Results:
- Evidence supports a threshold model for memory recollection.
- Retrieval failure occurs when the recollection threshold is not met.
- The developed technique accurately quantifies memory responses.
Conclusions:
- Memory recollection functions as a thresholded process.
- This finding clarifies a fundamental property of memory retrieval.
- Raises new questions about factors influencing retrieval success and age-related decline.
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