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The Temporal Signature of Memories: Identification of a General Mechanism for Dynamic Memory Replay in Humans.

ABSTRACT: Reinstatement of dynamic memories requires the replay of neural patterns that unfold over time in a similar manner as during perception. However, little is known about the mechanisms that guide such a temporally structured replay in humans, because previous studies used either unsuitable methods or paradigms to address this question. Here, we overcome these limitations by developing a new analysis method to detect the replay of temporal patterns in a paradigm that requires participants to mentally replay short sound or video clips. We show that memory reinstatement is accompanied by a decrease of low-frequency (8 Hz) power, which carries a temporal phase signature of the replayed stimulus. These replay effects were evident in the visual as well as in the auditory domain and were localized to sensory-specific regions. These results suggest low-frequency phase to be a domain-general mechanism that orchestrates dynamic memory replay in humans.

SUBMITTER: Michelmann S

PROVIDER: S-EPMC4975452 | biostudies-literature | 2016 Aug

REPOSITORIES: biostudies-literature

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The Temporal Signature of Memories: Identification of a General Mechanism for Dynamic Memory Replay in Humans.

Michelmann Sebastian S Bowman Howard H Hanslmayr Simon S

PLoS biology 20160805 8

Reinstatement of dynamic memories requires the replay of neural patterns that unfold over time in a similar manner as during perception. However, little is known about the mechanisms that guide such a temporally structured replay in humans, because previous studies used either unsuitable methods or paradigms to address this question. Here, we overcome these limitations by developing a new analysis method to detect the replay of temporal patterns in a paradigm that requires participants to mental ...[more]

PMID: 27494601

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