Young adult born neurons enhance hippocampal dependent performance via influences on bilateral networks
- Boston University, United States
- Massachusetts Institute of Technology, United States
Abstract
Adult neurogenesis supports performance in many hippocampal dependent tasks. Considering the small number of adult-born neurons generated at any given time, it is surprising that this sparse population of cells can substantially influence behavior. Recent studies have demonstrated that heightened excitability and plasticity may be critical for the contribution of young adult-born cells for certain tasks. What is not well understood is how these unique biophysical and synaptic properties may translate to networks that support behavioral function. Here we employed a location discrimination task in mice while using optogenetics to transiently silence adult-born neurons at different ages. We discovered that adult-born neurons promote location discrimination during early stages of development but only if they undergo maturation during task acquisition. Silencing of young adult-born neurons also produced changes extending to the contralateral hippocampus, detectable by both electrophysiology and fMRI measurements, suggesting young neurons may modulate location discrimination through influences on bilateral hippocampal networks.
Article and author information
Author details
Funding
NIH Office of the Director (1DP2NS082126)
- Xue Han
National Institute of Mental Health (5R00MH085944, 1R21MH109941)
- Xue Han
NIH Office of the Director (R01-DA028299)
- Alan P Jasanoff
Defense Advanced Research Projects Agency (W911NF-10-0059)
- Alan P Jasanoff
Pew Charitable Trusts
- Xue Han
American Federation for Aging Research
- Jia-Min Zhuo
Alfred P. Sloan Foundation
- Xue Han
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: All procedures involving animals were in accordance with the National Institutes of Health Guide for the care and use of Laboratory Animals, and approved by the Boston University and Massachusetts Institute of Technology Animal Care and Use Committee (protocol #'s: BU: 15-010; MIT: 1115-111-18).
Copyright
© 2016, Zhuo 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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Young adult born neurons enhance hippocampal dependent performance via influences on bilateral networks
eLife 5:e22429.
https://doi.org/10.7554/eLife.22429
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