Who do you trust? The impact of facial emotion and behaviour on decision making

Abstract

During social interactions, we use available information to guide our decisions, including behaviour and emotional displays. In some situations, behaviour and emotional displays may be incongruent, complicating decision making. This study had two main aims: first, to investigate the independent contributions of behaviour and facial displays of emotion on decisions to trust, and, second, to examine what happens when the information being signalled by a facial display is incongruent with behaviour. Participants played a modified version of the Trust Game in which they learned simulated players’ behaviour with or without concurrent displays of facial emotion. Results indicated that displays of anger, but not happiness, influenced decisions to trust during initial encounters. Over the course of repeated interactions, however, emotional displays consistent with an established pattern of behaviour made independent contributions to decision making, strengthening decisions to trust. When facial display and behaviour were incongruent, participants used current behaviour to inform decision making.

Keywords:

• Facial emotion
• Decision making
• Behaviour
• Trust Game

Notes

¹In the original study conducted by Berg and colleagues, the game was called the Investment Game. However, since other studies employing this paradigm have referred to the Investment Game as the Trust Game, we will henceforth refer to the Investment Game as the Trust Game for the purposes of clarity.