Local projections of layer Vb-to-Va are more prominent in lateral than in medial entorhinal cortex
- Tohoku University Graduate School of Life Sciences, Japan
- Norwegian University of Science and Technology, Norway
Abstract
The entorhinal cortex, in particular neurons in layer V, allegedly mediate transfer of information from the hippocampus to the neocortex, underlying long-term memory. Recently, this circuit has been shown to comprise a hippocampal output recipient layer Vb and a cortical projecting layer Va. With the use of in vitro electrophysiology in transgenic mice specific for layer Vb, we assessed the presence of the thus necessary connection from layer Vb-to-Va in the functionally distinct medial (MEC) and lateral (LEC) subdivisions; MEC, particularly its dorsal part, processes allocentric spatial information, whereas the corresponding part of LEC processes information representing elements of episodes. Using identical experimental approaches, we show that connections from layer Vb-to-Va neurons are stronger in dorsal LEC compared with dorsal MEC, suggesting different operating principles in these two regions. Although further in vivo experiments are needed, our findings imply a potential difference in how LEC and MEC mediate episodic systems-consolidation.
Data availability
All data generated or analyzed during this study are included in the manuscript and supporting files. We provide source data for Figure 1, 2, 3, 4, 5, Figure1-figure supplement 2, and Figure4-figure supplement 2.
Article and author information
Author details
Funding
Kavli Foundation (endowment)
- Menno P Witter
Norwegian Research Council (infrastructure grant NORBRAIN,#197467)
- Menno P Witter
Norwegian Research Council (the Centre of Excellence scheme - Centre for Neural Computation,#223262)
- Menno P Witter
Norwegian Research Council (research grant,# 227769)
- Menno P Witter
Ministry of Education, Culture, Sports, Science and Technology (KAKENHI,#19K06917)
- Shinya Ohara
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Katalin Toth, University of Ottawa, Canada
Ethics
Animal experimentation: All experiments were approved by the local ethics committee and were in accordance with the European Communities Council Directive and the Norwegian Experiments on Animals Act (#17898, #22312).
Version history
- Received: February 5, 2021
- Accepted: March 25, 2021
- Accepted Manuscript published: March 26, 2021 (version 1)
- Version of Record published: April 16, 2021 (version 2)
Copyright
© 2021, Ohara 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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Local projections of layer Vb-to-Va are more prominent in lateral than in medial entorhinal cortex
eLife 10:e67262.
https://doi.org/10.7554/eLife.67262
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