Intersubject similarity in neural representations underlies shared episodic memory content

Proc Natl Acad Sci U S A. 2023 Aug 29;120(35):e2308951120. doi: 10.1073/pnas.2308951120. Epub 2023 Aug 21.

Abstract

Individuals generally form their unique memories from shared experiences, yet the neural representational mechanisms underlying this subjectiveness of memory are poorly understood. The current study addressed this important question from the cross-subject neural representational perspective, leveraging a large functional magnetic resonance imaging dataset (n = 415) of a face-name associative memory task. We found that individuals' memory abilities were predicted by their synchronization to the group-averaged, canonical trial-by-trial activation level and, to a lesser degree, by their similarity to the group-averaged representational patterns during encoding. More importantly, the memory content shared between pairs of participants could be predicted by their shared local neural activation pattern, particularly in the angular gyrus and ventromedial prefrontal cortex, even after controlling for differences in memory abilities. These results uncover neural representational mechanisms for individualized memory and underscore the constructive nature of episodic memory.

Keywords: episodic memory; fMRI; intersubject analysis; memory encoding; neural representation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Humans
  • Memory, Episodic*
  • Parietal Lobe
  • Prefrontal Cortex / diagnostic imaging