title: Reinforcement learning signal predicts social conformity.
abstract: We often change our decisions and judgments to conform with normative group behavior. However, the neural mechanisms of social conformity remain unclear. Here we show, using functional magnetic resonance imaging, that conformity is based on mechanisms that comply with principles of reinforcement learning. We found that individual judgments of facial attractiveness are adjusted in line with group opinion. Conflict with group opinion triggered a neuronal response in the rostral cingulate zone and the ventral striatum similar to the "prediction error" signal suggested by neuroscientific models of reinforcement learning. The amplitude of the conflict-related signal predicted subsequent conforming behavioral adjustments. Furthermore, the individual amplitude of the conflict-related signal in the ventral striatum correlated with differences in conforming behavior across subjects. These findings provide evidence that social group norms evoke conformity via learning mechanisms reflected in the activity of the rostral cingulate zone and ventral striatum.
authors.affiliation: Donders Institute for Brain, Cognition, and Behaviour, Radboud University Nijmegen, 6500 HB Nijmegen, The Netherlands. v.klucharev@fcdonders.ru.nl
authors.forename: Vasily
authors.initials: V
authors.lastname: Klucharev
authors.forename: Kaisa
authors.initials: K
authors.lastname: Hytönen
authors.forename: Mark
authors.initials: M
authors.lastname: Rijpkema
authors.forename: Ale
authors.initials: A
authors.lastname: Smidts
authors.forename: Guillén
authors.initials: G
authors.lastname: Fernández
mesh_terms: D000328:Adult; D001519:Behavior / Q000502:physiology*; D001921:Brain / Q000033:anatomy & histology / Q000502:physiology; D001931:Brain Mapping; D003657:Decision Making / Q000502:physiology; D005260:Female; D006801:Humans; D007600:Judgment; D007858:Learning / Q000502:physiology*; D008279:Magnetic Resonance Imaging; D008959:Models, Neurological; D012054:Reinforcement, Psychology; D012925:Social Conformity; D055815:Young Adult