Emotional and social information conveyed by faces can be detected rapidly and implicitly by our brain and influence our decisions during social interactions. In a fMRI study using the Ultimatum games, a well-known economic game, we found that responder’s fairness judgment can be influenced by facial trustworthiness of proposer, and the lateral orbitofrontal cortex plays a key role in this process by integrating signals from various emotional structures such as the amygdala and the insula (Kim et al., Journal of Cognitive Neuroscience, 2012).