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bioRxiv · 10.1101/2021.09.15.460509

Relationships between individual differences in dual process and electrophysiological signatures of familiarity and recollection during retrieval

Abstract

Our everyday memories can vary in terms of accuracy and phenomenology. According to one theoretical account, these differences hinge on whether the memories contain information about both an item itself as well as associated details (remember) versus those that are devoid of these associated contextual details (familiar). This distinction has been supported by computational modeling of behavior, studies in patients, and neuroimaging work including differences both in electrophysiological and functional magnetic resonance imaging. At present, however, little evidence has emerged to suggest that neurophysiological measures track individual differences in estimates of recollection and familiarity. Here, we conducted electrophysiological recordings of brain activity during a recognition memory task designed to differentiate between behavioral indices of recollection and familiarity. Non-parametric cluster-based permutation analyses revealed associations between electrophysiological signatures of familiarity and recollection with their respective behavioral estimates. These results support the idea that recollection and familiarity are distinct phenomena and is the first, to our knowledge, to identify distinct electrophysiological signatures that track individual differences in these processes.

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Dimsdale-Zucker, H. R., Maciejewska, K., Kim, K., Yonelinas, A. P., Ranganath, C.. 2021-09-17. Relationships between individual differences in dual process and electrophysiological signatures of familiarity and recollection during retrieval. https://doi.org/10.1101/2021.09.15.460509

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