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Episodic memories are records of personally experienced events, coded neurally via the hippocampus and sur- rounding medial temporal lobe cortex. Information about the neural signal corresponding to a memory representation can be measured in fMRI data when the pattern across voxels is examined. Prior studies have found that similarity in the voxel patterns across repetition of a to-be-remembered stimulus predicts later memory retrieval, but the results are inconsistent across studies. The current study investigates the possibility that cognitive goals (defined here via the task instructions given to participants) during encoding affect the voxel pattern that will later support memory retrieval, and therefore that neural representations cannot be interpreted based on the stimulus alone. The behavioral results showed that exposure to variable cognitive tasks across repetition of events benefited subsequent memory retrieval. Voxel patterns in the hippocampus indicated a significant interaction between cognitive tasks (variable vs. consistent) and memory (remembered vs. forgotten) such that reduced voxel pattern similarity for repeated events with variable cognitive tasks, but not consistent cognitive tasks, sup- ported later memory success. There was no significant interaction in neural pattern similarity between cognitive tasks and memory success in medial temporal cortices or lateral occipital cortex. Instead, higher similarity in voxel patterns in right medial temporal cortices was associated with later memory retrieval, regardless of cognitive task. In conclusion, we found that the relationship between pattern similarity across repeated encoding and memory success in the hippocampus (but not medial temporal lobe cortex) changes when the cognitive task during encoding does or does not vary across repetitions of the event.
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This content will become publicly available on March 26, 2026
People display consistent recency and primacy effects in behavior and neural activity across perceptual and value-based judgments
Abstract Retrospective judgments require decision-makers to gather information over time and integrate that information into a summary statistic like the average. Many retrospective judgments require putting equal weight on early and late information, in contrast to prospective judgments that involve predicting the future and so rely more on late information. We investigate how people weight information over time when continuously reporting the average stimulus strength in a sequence of displays. We investigate the consistency of these temporal profiles across perceptual and value-based tasks using both behavior and functional magnetic resonance imaging (fMRI) data. We found that people display remarkably consistent temporal weighting functions across choice domains, with a generally strong recency bias and modest primacy bias. The fMRI data revealed evidence-tracking activity in the cuneus in both tasks and in the left dorsolateral prefrontal cortex in the value-based task. Finally, a network of cognitive control regions is more active for people who exhibit a stronger primacy vs. recency bias. Together, our behavioral findings indicate that people consistently overweight recency when evaluating past information, and the neural data suggest that overcoming this tendency may require cognitive control.
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- Award ID(s):
- 2333979
- PAR ID:
- 10617765
- Publisher / Repository:
- Springer
- Date Published:
- Journal Name:
- Cognitive, Affective, & Behavioral Neuroscience
- ISSN:
- 1530-7026
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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