title: Individual differences in extraversion and dopamine genetics predict neural reward responses.
abstract: Psychologists have linked the personality trait extraversion both to differences in reward sensitivity and to dopamine functioning, but little is known about how these differences are reflected in the functioning of the brain's dopaminergic neural reward system. Here, we show that individual differences in extraversion and the presence of the A1 allele on the dopamine D2 receptor gene predict activation magnitudes in the brain's reward system during a gambling task. In two functional MRI experiments, participants probabilistically received rewards either immediately following a behavioral response (Study 1) or after a 7.5 s anticipation period (Study 2). Although group activation maps revealed anticipation- and reward-related activations in the reward system, individual differences in extraversion and the presence of the D2 Taq1A allele predicted a significant amount of inter-subject variability in the magnitudes of reward-related, but not anticipation-related, activations. These results demonstrate a link between stable differences in personality, genetics, and brain functioning.
authors.affiliation: Department of Epileptology, University of Bonn, 53115 Bonn, Germany; Center for Neuroscience, University of California, Davis, CA 95616, USA. mcohen@ucdavis.edu
authors.forename: Michael X
authors.initials: MX
authors.lastname: Cohen
authors.forename: Jennifer
authors.initials: J
authors.lastname: Young
authors.forename: Jong-Min
authors.initials: JM
authors.lastname: Baek
authors.forename: Christopher
authors.initials: C
authors.lastname: Kessler
authors.forename: Charan
authors.initials: C
authors.lastname: Ranganath
mesh_terms: D000483:Alleles; D003463:Cues; D003627:Data Interpretation, Statistical; D003657:Decision Making / Q000502:physiology; D004298:Dopamine / Q000235:genetics*; D005120:Extraversion, Psychological; D005715:Gambling / Q000523:psychology; D006801:Humans; D007206:Individuality; D008279:Magnetic Resonance Imaging; D015233:Models, Statistical; D010556:Personality Tests; D011237:Predictive Value of Tests; D017448:Receptors, Dopamine D2 / Q000235:genetics; D012201:Reward; D012309:Risk-Taking
chemical_list: D017448:Receptors, Dopamine D2; D004298:Dopamine