Hippocampal ripples and their coordinated dialogue with the default mode network during recent and remote recollection.

ABSTRACT: Hippocampal ripples are prominent synchronization events generated by hippocampal neuronal assemblies. To date, ripples have been primarily associated with navigational memory in rodents and short-term episodic recollections in humans. Here, we uncover different profiles of ripple activity in the human hippocampus during the retrieval of recent and remote autobiographical events and semantic facts. We found that the ripple rate increased significantly before reported recall compared to control conditions. Patterns of ripple activity across multiple hippocampal sites demonstrated remarkable specificity for memory type. Intriguingly, these ripple patterns revealed a semantization dimension, in which patterns associated with autobiographical contents become similar to those of semantic memory

SUBMITTER: Norman Y 

PROVIDER: S-EPMC8693710 | biostudies-literature | 2021 Sep

REPOSITORIES: biostudies-literature