title: Behavioral contagion during learning about another agent's risk-preferences acts on the neural representation of decision-risk.
abstract: Our attitude toward risk plays a crucial role in influencing our everyday decision-making. Despite its importance, little is known about how human risk-preference can be modulated by observing risky behavior in other agents at either the behavioral or the neural level. Using fMRI combined with computational modeling of behavioral data, we show that human risk-preference can be systematically altered by the act of observing and learning from others' risk-related decisions. The contagion is driven specifically by brain regions involved in the assessment of risk: the behavioral shift is implemented via a neural representation of risk in the caudate nucleus, whereas the representations of other decision-related variables such as expected value are not affected. Furthermore, we uncover neural computations underlying learning about others' risk-preferences and describe how these signals interact with the neural representation of risk in the caudate. Updating of the belief about others' preferences is associated with neural activity in the dorsolateral prefrontal cortex (dlPFC). Functional coupling between the dlPFC and the caudate correlates with the degree of susceptibility to the contagion effect, suggesting that a frontal-subcortical loop, the so-called dorsolateral prefrontal-striatal circuit, underlies the modulation of risk-preference. Taken together, these findings provide a mechanistic account for how observation of others' risky behavior can modulate an individual's own risk-preference.
authors.affiliation: Division of the Humanities and Social Sciences, California Institute of Technology, Pasadena, CA 91125; shinsuke.szk@gmail.com.
authors.forename: Shinsuke
authors.initials: S
authors.lastname: Suzuki
authors.affiliation: Division of the Humanities and Social Sciences, California Institute of Technology, Pasadena, CA 91125;
authors.forename: Emily L S
authors.initials: EL
authors.lastname: Jensen
authors.affiliation: Faculty of Business and Economics, The University of Melbourne, Carlton, VIC 3010, Australia; Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, VIC 3052, Australia;
authors.forename: Peter
authors.initials: P
authors.lastname: Bossaerts
authors.affiliation: Division of the Humanities and Social Sciences, California Institute of Technology, Pasadena, CA 91125; Computation and Neural Systems, California Institute of Technology, Pasadena, CA 91125.
authors.forename: John P
authors.initials: JP
authors.lastname: O'Doherty
mesh_terms: D001290:Attitude; D001931:Brain Mapping; D002421:Caudate Nucleus / Q000502:physiology*; D003657:Decision Making / Q000502:physiology*; D006801:Humans; D007858:Learning / Q000502:physiology; D008279:Magnetic Resonance Imaging; D000067074:Peer Influence; D017397:Prefrontal Cortex / Q000502:physiology*; D012306:Risk; D012309:Risk-Taking
keywords: caudate; conformity; decision-making; neuroeconomics; risk