Neural mechanisms underlying human consensus decision-making

• Published in: Neuron (Cambridge, Mass.) Vol. 86; no. 2; pp. 591 - 602
• Main Authors: Suzuki, Shinsuke, Adachi, Ryo, Dunne, Simon, Bossaerts, Peter, O’Doherty, John P.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 22.04.2015; Elsevier Limited
• Subjects: Adolescent; Adult; Algorithms; Animals; Behavior; Brain Mapping; Choice Behavior - physiology; Consensus; Decision making; Decision Making - physiology; Design; Experiments; Female; Gyrus Cinguli - physiology; Humans; Hypotheses; Magnetic Resonance Imaging; Male; Models, Psychological; Models, Statistical; Neurosciences; Preferences; Prefrontal Cortex; Regression Analysis; Social Conformity; Studies; Young Adult
• ISSN: 0896-6273; 1097-4199; 1097-4199
• DOI: 10.1016/j.neuron.2015.03.019

Consensus building in a group is a hallmark of animal societies, yet little is known about its underlying computational and neural mechanisms. Here, we applied a novel computational framework to behavioral and fMRI data from human participants performing a consensus decision-making task with up to five other participants. We found that participants reached consensus decisions through integrating their own preferences with information about the majority of group-members’ prior choices, as well as inferences about how much each option was stuck to by the other people. These distinct decision variables were separately encoded in distinct brain areas: the ventromedial prefrontal cortex, posterior superior temporal sulcus/temporoparietal junction and intraparietal sulcus, and were integrated in the dorsal anterior cingulate cortex. Our findings provide support for a theoretical account in which collective decisions are made through integrating multiple types of inference about oneself, others and environments, processed in distinct brain modules.