The dynamic process of memory consolidation involves a
reorganization of brain regions that support a memory trace over
time, but exactly how the network reorganizes as the memory
changes remains unclear. We present novel converging evidence
from studies of animals (rats) and humans for the time-dependent
reorganization and transformation of different types of memory
as measured both by behavior and brain activation. We find that
context-specific memories in rats, and naturalistic episodic
memories in humans, lose precision over time and activity in the
hippocampus decreases. If, however, the retrieved memories
retain contextual or perceptual detail, the hippocampus is
engaged similarly at recent and remote timepoints. As the
interval between the timepoint increases, the medial prefrontal
cortex is engaged increasingly during memory retrieval,
regardless of the context or the amount of retrieved detail.
Moreover, these hippocampal-frontal shifts are accompanied by
corresponding changes in a network of cortical structures
mediating perceptually-detailed as well as less precise,
schematic memories. These findings provide cross-species
evidence for the crucial interplay between hippocampus and
neocortex that reflects changes in memory representation over
time and underlies systems consolidation.
%0 Journal Article
%1 Sekeres2018-io
%A Sekeres, Melanie J
%A Winocur, Gordon
%A Moscovitch, Morris
%A Anderson, John A E
%A Pishdadian, Sara
%A Martin Wojtowicz, J
%A St-Laurent, Marie
%A McAndrews, Mary Pat
%A Grady, Cheryl L
%D 2018
%I John Wiley & Sons, Inc. Hoboken, USA
%J Hippocampus
%K context_fear_conditioning episodic_memory fMRI hippocampus mPFC myown
%N 10
%P 745--764
%T Changes in patterns of neural activity underlie a time-dependent transformation of memory in rats and humans
%V 28
%X The dynamic process of memory consolidation involves a
reorganization of brain regions that support a memory trace over
time, but exactly how the network reorganizes as the memory
changes remains unclear. We present novel converging evidence
from studies of animals (rats) and humans for the time-dependent
reorganization and transformation of different types of memory
as measured both by behavior and brain activation. We find that
context-specific memories in rats, and naturalistic episodic
memories in humans, lose precision over time and activity in the
hippocampus decreases. If, however, the retrieved memories
retain contextual or perceptual detail, the hippocampus is
engaged similarly at recent and remote timepoints. As the
interval between the timepoint increases, the medial prefrontal
cortex is engaged increasingly during memory retrieval,
regardless of the context or the amount of retrieved detail.
Moreover, these hippocampal-frontal shifts are accompanied by
corresponding changes in a network of cortical structures
mediating perceptually-detailed as well as less precise,
schematic memories. These findings provide cross-species
evidence for the crucial interplay between hippocampus and
neocortex that reflects changes in memory representation over
time and underlies systems consolidation.
@article{Sekeres2018-io,
abstract = {The dynamic process of memory consolidation involves a
reorganization of brain regions that support a memory trace over
time, but exactly how the network reorganizes as the memory
changes remains unclear. We present novel converging evidence
from studies of animals (rats) and humans for the time-dependent
reorganization and transformation of different types of memory
as measured both by behavior and brain activation. We find that
context-specific memories in rats, and naturalistic episodic
memories in humans, lose precision over time and activity in the
hippocampus decreases. If, however, the retrieved memories
retain contextual or perceptual detail, the hippocampus is
engaged similarly at recent and remote timepoints. As the
interval between the timepoint increases, the medial prefrontal
cortex is engaged increasingly during memory retrieval,
regardless of the context or the amount of retrieved detail.
Moreover, these hippocampal-frontal shifts are accompanied by
corresponding changes in a network of cortical structures
mediating perceptually-detailed as well as less precise,
schematic memories. These findings provide cross-species
evidence for the crucial interplay between hippocampus and
neocortex that reflects changes in memory representation over
time and underlies systems consolidation.},
added-at = {2021-03-04T21:51:12.000+0100},
author = {Sekeres, Melanie J and Winocur, Gordon and Moscovitch, Morris and Anderson, John A E and Pishdadian, Sara and {Martin Wojtowicz}, J and St-Laurent, Marie and McAndrews, Mary Pat and Grady, Cheryl L},
biburl = {https://www.bibsonomy.org/bibtex/231080ddb0e8c4d8551b5e456e26846a3/janderz8},
interhash = {fe79fce1f12a7e04f308dea6eb3eabae},
intrahash = {31080ddb0e8c4d8551b5e456e26846a3},
journal = {Hippocampus},
keywords = {context_fear_conditioning episodic_memory fMRI hippocampus mPFC myown},
month = oct,
number = 10,
pages = {745--764},
publisher = {John Wiley {\&} Sons, Inc. Hoboken, USA},
timestamp = {2021-03-04T21:54:29.000+0100},
title = {{Changes in patterns of neural activity underlie a time-dependent transformation of memory in rats and humans}},
volume = 28,
year = 2018
}