title: Nucleus accumbens core and shell are differentially involved in general and outcome-specific forms of Pavlovian-instrumental transfer with alcohol and sucrose rewards.
abstract: Alcohol-associated stimuli contribute to relapse risk. Therefore, understanding the behavioural and neural mechanisms underlying the ability of such stimuli to promote alcohol-seeking is important for developing effective treatments for alcohol-use disorders. The Pavlovian-instrumental transfer (PIT) paradigm can be used to study the influence of Pavlovian cues on independently-trained instrumental responses earning reward. The effects can be either general, increasing the vigour of reward-related behaviours, or specific to responses that earn a common outcome. These different forms of PIT are mediated by distinct neural circuits involving the nucleus accumbens (NAC) core and shell, respectively. Here we examined the effects of pharmacological inactivation of either the NAC core or shell on PIT generated by alcohol-predictive and sucrose-predictive stimuli in rats. We found that presentations of a stimulus predicting sucrose enhanced responding for sucrose but not alcohol, suggesting an outcome-specific effect. In contrast, presentations of an alcohol-predictive stimulus enhanced responding for both alcohol and sucrose, suggesting a generally arousing effect. Inactivation of the NAC core reduced PIT and, in particular, the effect of the alcohol stimulus. Inactivation of the NAC shell reduced the specificity of the stimulus effects but left the ability of the stimuli to non-specifically invigorate responding intact, consistent with a role in mediating the specificity of PIT. Together, these results suggest that the NAC core plays a particularly important role in mediating the influence of alcohol-predictive cues on reward-seeking behaviours.
authors.affiliation: School of Psychology, University of Sydney, Sydney, NSW, 2006, Australia.
authors.forename: Laura H
authors.initials: LH
authors.lastname: Corbit
authors.affiliation: Department of Neurology, University of California at San Francisco, San Francisco, CA, USA.
authors.forename: Sarah C
authors.initials: SC
authors.lastname: Fischbach
authors.affiliation: Department of Neurology, University of California at San Francisco, San Francisco, CA, USA.|Department of Psychological and Brain Sciences, Krieger School of Arts and Sciences, Baltimore, MD, USA.|Department of Neuroscience, Johns Hopkins School of Medicine, Johns Hopkins University, Baltimore, MD, USA.
authors.forename: Patricia H
authors.initials: PH
authors.lastname: Janak
mesh_terms: D000428:Alcohol Drinking / Q000503:physiopathology*; D000818:Animals; D002492:Central Nervous System Depressants / Q000494:pharmacology; D003214:Conditioning, Classical; D003216:Conditioning, Operant; D000431:Ethanol / Q000494:pharmacology; D008297:Male; D009714:Nucleus Accumbens / Q000187:drug effects / Q000502:physiology*; D051381:Rats; D020318:Rats, Long-Evans; D012201:Reward; D013395:Sucrose / Q000494:pharmacology
chemical_list: D002492:Central Nervous System Depressants; D000431:Ethanol; D013395:Sucrose
keywords: incentive; learning; motivation; rat; stimulus; ventral striatum