Testosterone disrupts human collaboration by increasing egocentric choices.
Collaboration can provide benefits to the individual and the group across a variety of contexts. Even in simple perceptual tasks, the aggregation of individuals' personal information can enable enhanced group decision-making. However, in certain circumstances such collaboration can worsen performance, or even expose an individual to exploitation in economic tasks, and therefore a balance needs to be struck between a collaborative and a more egocentric disposition. Neurohumoral agents such as oxytocin are known to promote collaborative behaviours in economic tasks, but whether there are opponent agents, and whether these might even affect information aggregation without an economic component, is unknown. Here, we show that an androgen hormone, testosterone, acts as such an agent. Testosterone causally disrupted collaborative decision-making in a perceptual decision task, markedly reducing performance benefit individuals accrued from collaboration while leaving individual decision-making ability unaffected. This effect emerged because testosterone engendered more egocentric choices, manifest in an overweighting of one's own relative to others' judgements during joint decision-making. Our findings show that the biological control of social behaviour is dynamically regulated not only by modulators promoting, but also by those diminishing a propensity to collaborate.
Wellcome Trust Centre for Neuroimaging, Institute of Neurology, University College London, 12 Queen Square, London WC1N 3BG, UK. n.wright@fil.ion.ucl.ac.uk
Nicholas D
ND
Wright
Bahador
B
Bahrami
Emily
E
Johnson
Gina
G
Di Malta
Geraint
G
Rees
Christopher D
CD
Frith
Raymond J
RJ
Dolan
D000293:Adolescent; D000328:Adult; D002755:Choice Behavior; D003271:Contraceptive Agents, Female / Q000494:pharmacology; D003299:Cooperative Behavior; D018592:Cross-Over Studies; D003657:Decision Making / Q000187:drug effects*; D005260:Female; D006801:Humans; D013739:Testosterone / Q000031:analogs & derivatives / Q000097:blood* / Q000494:pharmacology; D055815:Young Adult
D003271:Contraceptive Agents, Female; D013739:Testosterone; C010792:testosterone undecanoate