title: The neural basis of altruistic punishment.
abstract: Many people voluntarily incur costs to punish violations of social norms. Evolutionary models and empirical evidence indicate that such altruistic punishment has been a decisive force in the evolution of human cooperation. We used H2 15O positron emission tomography to examine the neural basis for altruistic punishment of defectors in an economic exchange. Subjects could punish defection either symbolically or effectively. Symbolic punishment did not reduce the defector's economic payoff, whereas effective punishment did reduce the payoff. We scanned the subjects' brains while they learned about the defector's abuse of trust and determined the punishment. Effective punishment, as compared with symbolic punishment, activated the dorsal striatum, which has been implicated in the processing of rewards that accrue as a result of goal-directed actions. Moreover, subjects with stronger activations in the dorsal striatum were willing to incur greater costs in order to punish. Our findings support the hypothesis that people derive satisfaction from punishing norm violations and that the activation in the dorsal striatum reflects the anticipated satisfaction from punishing defectors.
authors.affiliation: Division of Psychiatry Research, University of Zurich, Lenggstrasse 31, 8029 Zurich, Switzerland. quervain@bli.unizh.ch
authors.forename: Dominique J-F
authors.initials: DJ
authors.lastname: de Quervain
authors.forename: Urs
authors.initials: U
authors.lastname: Fischbacher
authors.forename: Valerie
authors.initials: V
authors.lastname: Treyer
authors.forename: Melanie
authors.initials: M
authors.lastname: Schellhammer
authors.forename: Ulrich
authors.initials: U
authors.lastname: Schnyder
authors.forename: Alfred
authors.initials: A
authors.lastname: Buck
authors.forename: Ernst
authors.initials: E
authors.lastname: Fehr
mesh_terms: D000328:Adult; D000533:Altruism; D001931:Brain Mapping; D002421:Caudate Nucleus / Q000000981:diagnostic imaging / Q000502:physiology*; D003342:Corpus Striatum / Q000000981:diagnostic imaging / Q000502:physiology*; D004644:Emotions; D005625:Frontal Lobe / Q000000981:diagnostic imaging / Q000502:physiology; D005717:Games, Experimental; D006801:Humans; D008297:Male; D010549:Personal Satisfaction; D017397:Prefrontal Cortex / Q000000981:diagnostic imaging / Q000502:physiology; D011678:Punishment; D012201:Reward; D011795:Surveys and Questionnaires; D013788:Thalamus / Q000000981:diagnostic imaging / Q000502:physiology; D014055:Tomography, Emission-Computed