The power of words:  Neural substrates underlying communication in signaling games

Ming Hsu
University of California, Berkeley

Communication is a ubiquitous feature of social interactions across multiple species, and despite its 
clear importance in social behavior, there has been little work in attempting to understand the neural 
mechanisms mediating social communication and behavior. In this study, we combined an economic 
game with functional magnetic resonance imaging (fMRI) to investigate the neural substrates underlying 
an important class of social communication: honesty vs. deception.  Our results suggest that individuals 
choose to communicate honestly at the cost of self-interest. Importantly, different brain regions 
separately encode the cost and benefit of deception during the decision-making process. In particular, 
the potential benefit from deception correlates with the neural activity in ventromedial prefrontal 
cortex (VMPFC), whereas the potential cost of deception is associated with the neural signal in bilateral 
insula. These findings suggest that honest communication emerges from a reward-based comparison 
process in the brain and point to future investigation into the neurobehavioral mechanism underlying 
various modulators of social communication.