Optogenetic dissection of basolateral amygdala contributions to intertemporal choice in young and aged rats
Abstract
Across species, aging is associated with an increased ability to choose delayed over immediate gratification. These experiments used young and aged rats to test the role of the basolateral amygdala (BLA) in intertemporal decision making. An optogenetic approach was used to inactivate the BLA in young and aged rats at discrete time points during choices between levers that yielded a small, immediate vs. a large, delayed food reward. BLA inactivation just prior to decisions attenuated impulsive choice in both young and aged rats. In contrast, inactivation during receipt of the small, immediate reward increased impulsive choice in young rats but had no effect in aged rats. BLA inactivation during the delay or intertrial interval had no effect at either age. These data demonstrate that the BLA plays multiple, temporally distinct roles during intertemporal choice, and show that the contribution of BLA to choice behavior changes across the lifespan.
Data availability
All data generated or analyzed during this study are included in the manuscript and supporting files.
Article and author information
Author details
Funding
National Institutes of Health (R01AG029421)
- Jennifer L Bizon
McKnight Brain Research Foundation
- Jennifer L Bizon
McKnight Foundation
- Caesar M Hernandez
Thomas H. Maren Foundation
- Caitlin A Orsini
National Institutes of Health (RF1AG060778)
- Charles J Frazier
- Barry Setlow
- Jennifer L Bizon
National Institutes of Health (K99DA041493)
- Caitlin A Orsini
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Geoffrey Schoenbaum, National Institute on Drug Abuse, National Institutes of Health, United States
Ethics
Animal experimentation: This research was conducted in accordance with the rules and regulations of the University of Florida Institutional Animal Care and Use Committee (protocol number 201604961) and National Institutes of Health guidelines.
Version history
- Received: February 18, 2019
- Accepted: April 23, 2019
- Accepted Manuscript published: April 24, 2019 (version 1)
- Version of Record published: May 22, 2019 (version 2)
Copyright
© 2019, Hernandez 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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