First impressions of child faces: Facial trustworthiness influences adults' interpretations of children's behavior in ambiguous situations.

Despite the profound behavioral consequences that first impressions of trustworthiness have on adult populations, few studies have examined how adults' first impressions of trustworthiness influence behavioral outcomes for children. Using a novel task design, we examined adults' perceptions of children's behavior in ambiguous situations. After a brief presentation of a child's face (high trust or low trust), participants viewed the child's face embedded within an ambiguous scene involving two children (Scene Task) or read a vignette about a misbehavior done by that child (Misbehavior Task). In the Scene Task, participants described what they believed to be happening in each scene; in the Misbehavior Task, participants indicated whether the behavior was done on purpose or by accident. In both tasks, participants also rated the behavior of the target child and indicated whether that child would be a good friend. In Experiment 1, young adults (n = 61) and older adults (n = 57) viewed unaltered face images. In Experiment 2, young adults (N = 59) completed the same tasks while viewing images of child faces morphed toward high-trust and low-trust averages. In both experiments, ambiguous scenes and misbehaviors were interpreted more positively when the target child had a high-trust face versus a low-trust face, with comparable patterns of results for the two age groups. Collectively, our results demonstrate that a child's facial trustworthiness biases how adults interpret children's behavior-a heuristic that may have lasting behavioral consequences for children through a self-fulfilling prophecy.