Hippocampal Neurons Code Individual Episodic Memories in Humans

Overview

Journal Nat Hum Behav

Specialties Psychology
Social Sciences

Date 2023 Oct 5

PMID 37798368

Authors

Luca D Kolibius

Frederic Roux

George Parish

Marije Ter Wal

Mircea van der Plas

Ramesh Chelvarajah

Vijay Sawlani

David T Rollings

Johannes D Lang

Stephanie Gollwitzer

Katrin Walther

Rudiger Hopfengartner

Gernot Kreiselmeyer

Hajo Hamer

Bernhard P Staresina

Maria Wimber

Howard Bowman

Simon Hanslmayr

Affiliations

Soon will be listed here.

Abstract

The hippocampus is an essential hub for episodic memory processing. However, how human hippocampal single neurons code multi-element associations remains unknown. In particular, it is debated whether each hippocampal neuron represents an invariant element within an episode or whether single neurons bind together all the elements of a discrete episodic memory. Here we provide evidence for the latter hypothesis. Using single-neuron recordings from a total of 30 participants, we show that individual neurons, which we term episode-specific neurons, code discrete episodic memories using either a rate code or a temporal firing code. These neurons were observed exclusively in the hippocampus. Importantly, these episode-specific neurons do not reflect the coding of a particular element in the episode (that is, concept or time). Instead, they code for the conjunction of the different elements that make up the episode.

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