Looking into recent and remote past: Meta-analytic evidence for cortical re-organization of episodic autobiographical memories

Abstract

Episodic autobiographical memory (EAM) is pivotal for the development and maintenance of personal identity. However, a theoretical debate still exists about where EAMs are stored in our brain and about hippocampal unique contribution to their recollection. Here we disentangled this issue performing an Activation Likelihood Estimation (ALE) meta-analysis on 79 neuroimaging experiments, classified according to the remoteness of EAMs, and meta-analytic connectivity modeling. A wide brain network, spanning from occipital to frontal lobe, was involved in recalling EAMs. However, remote and recent EAMs were processed by different nodes of this network: recent EAMs activated angular gyrus, dorsomedial prefrontal cortex and hippocampus/parahippocampal gyrus, that we found to be connected with its contralateral homologous, bilateral middle cingulate cortex, left inferior frontal gyrus and left superior parietal lobule. Instead, remote EAMs activated posterior cingulate cortex, that we found to be connected with hippocampus/parahippocampal gyrus. These results provide new important evidence for the theoretical discussion about where and how EAMs are stored in the brain and new exciting insights into hippocampal contribution to EAM.

Keywords: Declarative memory; Hippocampus; Memory; Time; fMRI.