Memory recall involves a transient break in excitatory-inhibitory balance
Abstract
The brain has a remarkable capacity to acquire and store memories that can later be selectively recalled. These processes are supported by the hippocampus which is thought to index memory recall by reinstating information stored across distributed neocortical circuits. However, the mechanism that supports this interaction remains unclear. Here, in humans, we show that recall of a visual cue from a paired associate is accompanied by a transient increase in the ratio between glutamate and GABA in visual cortex. Moreover, these excitatory-inhibitory fluctuations are predicted by activity in the hippocampus. These data suggest the hippocampus gates memory recall by indexing information stored across neocortical circuits using a disinhibitory mechanism.
Data availability
The data and code used in this study are available via the MRC BNDU Data Sharing PlatformThe data is available here:https://data.mrc.ox.ac.uk/data-set/fmri-fmrs-inferenceDOI: https://doi.org/10.5287/bodleian:vmJOOm7KDThe code is available here:https://data.mrc.ox.ac.uk/data-set/frms-codeDOI: https://doi.org/10.5287/bodleian:8JwYayQmD
Article and author information
Author details
Funding
Engineering and Physical Sciences Research Council (EP/L016052/1)
- Renée S Koolschijn
Royal Society Dorothy Hodgkin Research Fellowship
- I Betina Ip
Wellcome Trust (203836/Z/16/Z)
- Anna Shpektor
Biotechnology and Biological Sciences Research Council (BB/N0059TX/1)
- David Dupret
Medical Research Council (MC_UU_12024/3)
- David Dupret
John Fell Fund, University of Oxford (153/046)
- Helen C Barron
Wellcome Centre for Integrative Neuroimaging (Seed grant)
- Helen C Barron
Merton College, University of Oxford (JRF)
- Helen C Barron
Medical Research Council (MC_UU_12024/3)
- Helen C Barron
Wellcome Trust (203139/Z/16/Z)
- Renée S Koolschijn
- Anna Shpektor
- William T Clarke
- I Betina Ip
- Helen C Barron
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Human subjects: All participants gave informed written consent.All experiments were approved by the University of Oxford ethics committee (reference number R43594/RE001).
Copyright
© 2021, Koolschijn et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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