title: Dopamine modulates novelty seeking behavior during decision making.
abstract: Novelty seeking refers to the tendency of humans and animals to explore novel and unfamiliar stimuli and environments. The idea that dopamine modulates novelty seeking is supported by evidence that novel stimuli excite dopamine neurons and activate brain regions receiving dopaminergic input. In addition, dopamine is shown to drive exploratory behavior in novel environments. It is not clear whether dopamine promotes novelty seeking when it is framed as the decision to explore novel options versus the exploitation of familiar options. To test this hypothesis, we administered systemic injections of saline or GBR-12909, a selective dopamine transporter (DAT) inhibitor, to monkeys and assessed their novelty seeking behavior during a probabilistic decision making task. The task involved pseudorandom introductions of novel choice options. This allowed monkeys the opportunity to explore novel options or to exploit familiar options that they had already sampled. We found that DAT blockade increased the monkeys' preference for novel options. A reinforcement learning (RL) model fit to the monkeys' choice data showed that increased novelty seeking after DAT blockade was driven by an increase in the initial value the monkeys assigned to novel options. However, blocking DAT did not modulate the rate at which the monkeys learned which cues were most predictive of reward or their tendency to exploit that knowledge. These data demonstrate that dopamine enhances novelty-driven value and imply that excessive novelty seeking-characteristic of impulsivity and behavioral addictions-might be caused by increases in dopamine, stemming from less reuptake.
authors.affiliation: Laboratory of Neuropsychology, National Institute of Mental Health, National Institutes of Health.
authors.forename: Vincent D
authors.initials: VD
authors.lastname: Costa
authors.affiliation: Laboratory of Neuropsychology, National Institute of Mental Health, National Institutes of Health.
authors.forename: Valery L
authors.initials: VL
authors.lastname: Tran
authors.affiliation: Laboratory of Neuropsychology, National Institute of Mental Health, National Institutes of Health.
authors.forename: Janita
authors.initials: J
authors.lastname: Turchi
authors.affiliation: Laboratory of Neuropsychology, National Institute of Mental Health, National Institutes of Health.
authors.forename: Bruno B
authors.initials: BB
authors.lastname: Averbeck
mesh_terms: D000818:Animals; D002755:Choice Behavior / Q000187:drug effects / Q000502:physiology*; D004298:Dopamine / Q000378:metabolism*; D050483:Dopamine Plasma Membrane Transport Proteins / Q000037:antagonists & inhibitors / Q000378:metabolism; D018765:Dopamine Uptake Inhibitors / Q000494:pharmacology; D005106:Exploratory Behavior / Q000187:drug effects / Q000502:physiology*; D008253:Macaca mulatta; D008297:Male; D008960:Models, Psychological; D009483:Neuropsychological Tests; D010879:Piperazines / Q000494:pharmacology; D011336:Probability; D012054:Reinforcement, Psychology
chemical_list: D050483:Dopamine Plasma Membrane Transport Proteins; D018765:Dopamine Uptake Inhibitors; D010879:Piperazines; C043425:vanoxerine; D004298:Dopamine