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Time cells in the human hippocampus and entorhinal cortex support episodic memory.

ABSTRACT: The organization of temporal information is critical for the encoding and retrieval of episodic memories. In the rodent hippocampus and entorhinal cortex, evidence accumulated over the last decade suggests that populations of "time cells" in the hippocampus encode temporal information. We identify time cells in humans using intracranial microelectrode recordings obtained from 27 human epilepsy patients who performed an episodic memory task. We show that time cell activity predicts the temporal organization of retrieved memory items. We also uncover evidence of ramping cell activity in humans, which represents a complementary type of temporal information. These findings establish a cellular mechanism for the representation of temporal information in the human brain needed to form episodic memories.

SUBMITTER: Umbach G

PROVIDER: S-EPMC7668099 | biostudies-literature | 2020 Nov

REPOSITORIES: biostudies-literature

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Time cells in the human hippocampus and entorhinal cortex support episodic memory.

Umbach Gray G Kantak Pranish P Jacobs Joshua J Kahana Michael M Pfeiffer Brad E BE Sperling Michael M Lega Bradley B

Proceedings of the National Academy of Sciences of the United States of America 20201027 45

The organization of temporal information is critical for the encoding and retrieval of episodic memories. In the rodent hippocampus and entorhinal cortex, evidence accumulated over the last decade suggests that populations of "time cells" in the hippocampus encode temporal information. We identify time cells in humans using intracranial microelectrode recordings obtained from 27 human epilepsy patients who performed an episodic memory task. We show that time cell activity predicts the temporal o ...[more]

PMID: 33109718

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