Familiar faces facilitate perspective-taking in children.

Familiar faces elicit more confident and interactive behaviour in adults than unfamiliar faces. However, it remains unclear whether familiarity influences children's social functioning. Here, we investigated how face familiarity would affect 9- to 11-year-old children's perspective-taking ability. We assessed perspective-taking ability with an adapted version of the Director Task where the Director's face was a picture of a familiar peer or a stranger. In Study 1 (N = 34), children showed a higher perspective-taking ability when facing a familiar peer than a stranger. In Study 2 and Study 3 (N = 30 respectively), children built up familiarity with originally unfamiliar faces through either social interaction or person knowledge learning. Face familiarity developed through social interaction but not person knowledge learning promoted children's subsequent perspective-taking ability. Based on these findings, we propose a link between face familiarity and social functioning, which can quickly set the mind to different socially prepared states.