Dopaminergic genes are associated with both directed and random exploration

• Main Authors: Gershman, S.J (Author), Tzovaras, B.G (Author)
• Format: Article
• Language: English
• Published: Elsevier Ltd 2018
• Subjects: adolescent; Adolescent; adult; Adult; aged; Aged; Article; Bayesian inference; catechol methyltransferase; Catechol O-Methyltransferase; Choice Behavior; COMT protein, human; decision making; directed exploration; Dopamine and cAMP-Regulated Phosphoprotein 32; dopaminergic gene; dopaminergic transmission; exploratory behavior; Exploratory Behavior; Explore-exploit dilemma; female; Female; gene; genetic association; genetic linkage; genetic variation; genetics; human; Humans; individuality; Individuality; male; Male; mathematical model; messenger RNA; middle aged; Middle Aged; neuromodulation; normal distribution; phosphoprotein DARPP 32; Polymorphism, Single Nucleotide; PPP1R1B protein, human; prediction; random exploration; reinforcement; Reinforcement (Psychology); Reinforcement learning; single nucleotide polymorphism; stochastic model; uncertainty; Uncertainty; young adult; Young Adult
• Online Access: View Fulltext in Publisher

 In order to maximize long-term rewards, agents must balance exploitation (choosing the option with the highest payoff) and exploration (gathering information about options that might have higher payoffs). Although the optimal solution to this trade-off is intractable, humans make use of two effective strategies: selectively exploring options with high uncertainty (directed exploration), and increasing the randomness of their choices when they are more uncertain (random exploration). Using a task that independently manipulates these two forms of exploration, we show that single nucleotide polymorphisms related to dopamine are associated with individual differences in exploration strategies. Variation in a gene linked to prefrontal dopamine (COMT) predicted the degree of directed exploration, as well as the overall randomness of responding. Variation in a gene linked to striatal dopamine (DARPP-32) predicted the degree of both directed and random exploration. These findings suggest that dopamine makes multiple contributions to exploration, depending on its afferent target. © 2018 Elsevier Ltd