Functional heterogeneity within the rodent lateral orbitofrontal cortex dissociates outcome devaluation and reversal learning deficits
The orbitofrontal cortex (OFC) is critical for updating reward-directed behaviours flexibly when outcomes are devalued or when task contingencies are reversed. Failure to update behaviour in outcome devaluation and reversal learning procedures are considered canonical deficits following OFC lesions in non-human primates and rodents. We examined the generality of these findings in rodents using lesions of the rodent lateral OFC (LO) in instrumental action-outcome and Pavlovian cue-outcome devaluation procedures. LO lesions disrupted outcome devaluation in Pavlovian but not instrumental procedures. Furthermore, although both anterior and posterior LO lesions disrupted Pavlovian outcome devaluation, only posterior LO lesions were found to disrupt reversal learning. Posterior but not anterior LO lesions were also found to disrupt the attribution of motivational value to Pavlovian cues in sign-tracking. These novel dissociable task- and subregion-specific effects suggest a way to reconcile contradictory findings between rodent and non-human primate OFC research.
All experimental data publicly available at Dryad Digital Repository. doi:10.5061/dryad.c3b0260
Data from: The rodent lateral orbitofrontal cortex represents expected Pavlovian outcome value but not identityAvailable at Dryad Digital Repository under a CC0 Public Domain Dedication.
Article and author information
Australian Research Council (DP0989027)
- Simon Killcross
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Animal experimentation: All animal research was carried out in accordance with the National Institute of Health Guide for the Care and Use of Laboratories Animals (NIH publications No. 80-23, revised 1996) and approved by the University of New South Wales Animal Care and Ethics Committee.
- Geoffrey Schoenbaum, National Institute on Drug Abuse, National Institutes of Health, United States
- Received: April 7, 2018
- Accepted: July 24, 2018
- Accepted Manuscript published: July 25, 2018 (version 1)
- Version of Record published: August 20, 2018 (version 2)
© 2018, Panayi & Killcross
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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