Emotional feedback is a crucial part of social interaction, since it may indicate motivations, intentions, and thus, the future behavior of interaction partners. Nowadays, social interaction has been enriched by artificial emotional feedback provided by emojis, which are the means of transporting emotions in mobile messengers. In this study, we examined the influence of emotional feedback by emojis compared to real faces on decision-making and neural processing. We modified the ultimatum game by including proposers represented both by emojis and human faces who reacted specifically toward acceptance or rejection of an offer. We show that proposers who reward acceptance with a smile cause the highest acceptance rates. Interestingly, acceptance rates did not differ between proposers represented by humans compared to emojis. Regarding electrophysiology, emojis evoked more negative N170 and N2 brain potentials compared to human faces both during a mere presentation and as feedback stimuli. Proposers that showed emotional facial expressions evoked larger N170 amplitudes as compared to neutral expressions. Especially the proposers represented by emojis evoked larger P3 amplitudes as feedback stimuli compared to human facial expressions. The comparison of emoji proposers with real-face proposers provides new insight into how relevant social cues influence behavior and its neural underpinnings.
Keywords: Decision-making; emojis; emotional feedback; facial expression; ultimatum game.