Tracking the relation between gist and item memory over the course of long-term memory consolidation
- University of Pennsylvania, United States
Abstract
Our experiences in the world support memories not only of specific episodes but also of the generalities (the ‘gist’) across related experiences. It remains unclear how these two types of memories evolve and influence one another over time. In two experiments, 173 human participants encoded spatial locations from a distribution and reported both item memory (specific locations) and gist memory (center for the locations) across one to two months. Experiment 1 demonstrated that after one month, gist memory was preserved relative to item memory, despite a persistent positive correlation between them. Critically, item memories were biased towards the gist over time. Experiment 2 showed that a spatial outlier item changed this relationship and that the extraction of gist is sensitive to the regularities of items. Our results suggest that the gist starts to guide item memories over longer durations as their relative strengths change.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files.
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Author details
Funding
National Institute of Health (Linguistic and NonLinguistic Functions of Frontal Cortex,R01 DC009209)
- Sharon Thompson-Schill
National Institute of Health (5R01DC009209-14)
- Sharon Thompson-Schill
National Institute of Health (5R01DC015359-05)
- Sharon Thompson-Schill
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Human subjects: That informed consent, and consent to publish, was obtained. The specific ethical approval obtained from University of Pennsylvania IRB (IRB #705915, Linguistic and Nonlinguistic Functions of Frontal Cortex). The guidelines were followed. The above information was described in the Materials and Methods.
Copyright
© 2021, Zeng et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Tracking the relation between gist and item memory over the course of long-term memory consolidation
eLife 10:e65588.
https://doi.org/10.7554/eLife.65588
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