Self-serving dishonest decisions can show facilitated cognitive dynamics.

We use a novel task to test two competing hypotheses concerning the cognitive processes involved in dishonesty. Many existing accounts of deception imply that in order to act dishonestly one has to use cognitive control to overcome a bias toward the truth, which results in more time and effort. A recent hypothesis suggests that lying in order to serve self-interest may be a rapid, even automatic tendency taking less time than refraining from lying. In the current study, we track the action dynamics of potentially dishonest decisions to investigate the underlying cognitive processes. Participants are asked to privately predict the outcome of a virtual coin flip, report their accuracy and receive bonus credit for accurate predictions. The movements of the computer cursor toward the target answer are recorded and used to characterize the dynamics of decisions. Our results suggest that when a self-serving condition holds, decisions that have a high probability of being dishonest take less time and experience less hesitation.