title: Serotonin and social norms: tryptophan depletion impairs social comparison and leads to resource depletion in a multiplayer harvesting game.
abstract: How do people sustain resources for the benefit of individuals and communities and avoid the tragedy of the commons, in which shared resources become exhausted? In the present study, we examined the role of serotonin activity and social norms in the management of depletable resources. Healthy adults, alongside social partners, completed a multiplayer resource-dilemma game in which they repeatedly harvested from a partially replenishable monetary resource. Dietary tryptophan depletion, leading to reduced serotonin activity, was associated with aggressive harvesting strategies and disrupted use of the social norms given by distributions of other players' harvests. Tryptophan-depleted participants more frequently exhausted the resource completely and also accumulated fewer rewards than participants who were not tryptophan depleted. Our findings show that rank-based social comparisons are crucial to the management of depletable resources, and that serotonin mediates responses to social norms.
authors.affiliation: Department of Psychiatry, University of Oxford.
authors.forename: Amy C
authors.initials: AC
authors.lastname: Bilderbeck
authors.affiliation: Department of Psychology, University of Warwick.
authors.forename: Gordon D A
authors.initials: GD
authors.lastname: Brown
authors.affiliation: Nuffield Department of Primary Healthcare Sciences, University of Oxford.
authors.forename: Judi
authors.initials: J
authors.lastname: Read
authors.affiliation: Oxford Centre for Human Brain Activity, University of Oxford.
authors.forename: Mark
authors.initials: M
authors.lastname: Woolrich
authors.affiliation: Department of Psychiatry, University of Oxford.
authors.forename: Phillip J
authors.initials: PJ
authors.lastname: Cowen
authors.affiliation: Oxford Centre for Functional MRI of the Brain, University of Oxford.
authors.forename: Tim E J
authors.initials: TE
authors.lastname: Behrens
authors.affiliation: School of Psychology, Bangor University r.rogers@bangor.ac.uk.
authors.forename: Robert D
authors.initials: RD
authors.lastname: Rogers
mesh_terms: D000328:Adult; D005260:Female; D064368:Healthy Volunteers; D006801:Humans; D008297:Male; D012044:Regression Analysis; D012201:Reward; D057566:Self Report; D012701:Serotonin / Q000502:physiology*; D012919:Social Behavior; D066262:Social Norms; D014364:Tryptophan / Q000008:administration & dosage / Q000502:physiology*; D055815:Young Adult
chemical_list: D012701:Serotonin; D014364:Tryptophan
keywords: neurotransmitters; social behavior; social influences