Neuroscience & Psychology Postgraduate Society Seminars

Can you judge a "crook" by their cover?

Faces can impact on judgements, and perceptions of trustworthiness. While previous research has produced mixed results, there have been suggestions that accurate judgements are often possible using only facial information. Related to this are the findings that smiling promotes positive judgements of trustworthiness, while frowning results in more negative judgements. It has also been shown that additional deliberation can negatively impact decisions, including facial judgements. Here we show that accurate trustworthiness judgements, based on a 'real world' common measure can be made from faces, specifically by using expression. This accuracy was also shown to decrease as deliberation increased. This contrasts with previous suggestions that such 'cheater detection' was only possible if viewing a face at the moment of deception. It also expands on previous research that showed similar results but this study uses a common measure whereby the distinction of relative trustworthiness is more internally valid. One characteristic of the effect is that accuracy increases with less deliberation, which indicates that the process is somewhat automatic. Given the implications in areas such as the criminal courts, or in political elections, this finding provides a valuable insight in to the processes that make humans cooperate and trust.