Theory of mind, executive function, and lying in children: a meta-analysis.

Scientific research on how children learn to tell lies has existed for more than a century. Earlier studies mainly focused on moral, social, and situational factors contributing to the development of lying. Researchers have only begun to explore the cognitive correlations of children's lying in the last two decades. Cognitive theories suggest that theory of mind (ToM) and executive function (EF) should be closely related to the development of lying since lying is, in essence, ToM and EF in action. Yet, findings from empirical studies are mixed. To address this issue, the current meta-analysis reviewed all prior literature that examined the relations between children's lying and ToM and/or between children's lying and EF. In total, 47 papers consisting of 5099 participants between 2 and 19 years of age were included, which yielded 74 effect sizes for ToM and 94 effect sizes for EF. Statistically significant but relatively small effects were found between children's lying and ToM (r = .17) and between lying and EF (r = .13). Furthermore, EF's correlation with children's initial lies was significantly smaller than its correlation with children's ability to maintain lies. This comprehensive meta-analysis provides a clear picture of the associations between children's ToM/EF and their lying behavior and confirms that ToM and EF indeed play a positive role in children's lying and its development.