Distinct memory engrams in the infralimbic cortex of rats control opposing environmental actions on a learned behavior
- The Scripps Research Institute, United States
- University of Sussex, United Kingdom
- University of California San Diego, United States
- National Institute on Drug Abuse, United States
Abstract
Conflicting evidence exists regarding the role of infralimbic cortex (IL) in the environmental control of appetitive behavior. Inhibition of IL, irrespective of its intrinsic neural activity, attenuates not only the ability of environmental cues predictive of reward availability to promote reward seeking, but also the ability of environmental cues predictive of reward omission to suppress this behavior. Here we report that such bidirectional behavioral modulation in rats is mediated by functionally distinct units of neurons (neural ensembles) that are concurrently localized within the same IL brain area but selectively reactive to different environmental cues. Ensemble-specific neural activity is thought to function as a memory engram representing a learned association between environment and behavior. Our findings establish the causal evidence for the concurrent existence of two distinct engrams within a single brain site, each mediating opposing environmental actions on a learned behavior.
Article and author information
Author details
Funding
National Institute on Drug Abuse (R21DA033533)
- Nobuyoshi Suto
National Institute on Alcohol Abuse and Alcoholism (R01AA023183)
- Nobuyoshi Suto
National Institute on Drug Abuse (R01DA037294)
- Nobuyoshi Suto
National Institute on Alcohol Abuse and Alcoholism (R01AA021549)
- Friedbert Weiss
National Institute on Drug Abuse (ZIADA000467)
- Bruce T Hope
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 experimental procedures were conducted in adherence to the National Institutes of Health Guide for the Care and Use of Laboratory Animals and were approved by the Institutional Animal Care and Use Committee of The Scripps Research Institute. (animal protocol #12-0032).
Copyright
© 2016, Suto 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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Distinct memory engrams in the infralimbic cortex of rats control opposing environmental actions on a learned behavior
eLife 5:e21920.
https://doi.org/10.7554/eLife.21920
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