title: Dopamine D2 Modulation of Sign and Goal Tracking in Rats.
abstract: In Pavlovian conditioning, sign- and goal-tracking behaviors represent different approaches towards the conditioned stimulus. These behavioral patterns have been associated with predictive or incentive properties of the conditioned stimulus, with a crucial involvement of the mesolimbic dopamine system. As it is possible that sign tracking behavior is more sensitive to dopamine modulation, we evaluated the dopamine-dependence of sign- and goal-tracking behavior. We assessed responses to both a D2 agonist and an antagonist, and tested performance in a behavioral paradigm known to activate dopamine projections and in an animal model that affects mesolimbic and mesocortical function. Sign trackers displayed a greater sensitivity to a D2 agonist and smaller prepulse inhibition of the acoustic startle response than goal trackers, suggesting a reduced inhibitory ability. In addition, a neonatal ventral hippocampal lesion resulted in the loss of incentive salience of cues in sign trackers. Overall, these data indicate that sign-tracking behavior is more heavily controlled by dopamine than goal tracking.
authors.affiliation: 1] Departamento de Psicología Experimental, Universidad de Sevilla, Sevilla, Spain [2] Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, MD, USA.
authors.forename: Juan Carlos
authors.initials: JC
authors.lastname: Lopez
authors.affiliation: Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, MD, USA.
authors.forename: Rose-Marie
authors.initials: RM
authors.lastname: Karlsson
authors.affiliation: 1] Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, MD, USA [2] Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD, USA.
authors.forename: Patricio
authors.initials: P
authors.lastname: O'Donnell
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D000831:Animals, Newborn; D003214:Conditioning, Classical / Q000187:drug effects / Q000502:physiology*; D003216:Conditioning, Operant / Q000187:drug effects / Q000502:physiology; D003463:Cues; D018492:Dopamine Antagonists / Q000494:pharmacology; D006040:Goals; D008297:Male; D009042:Motivation / Q000502:physiology*; D065808:Prepulse Inhibition / Q000187:drug effects / Q000502:physiology; D051381:Rats; D020318:Rats, Long-Evans; D017448:Receptors, Dopamine D2 / Q000378:metabolism*; D013216:Reflex, Startle / Q000187:drug effects; D012457:Salicylamides / Q000494:pharmacology
chemical_list: D018492:Dopamine Antagonists; D017448:Receptors, Dopamine D2; D012457:Salicylamides; C045989:eticlopride