Selective trust in young children and distracted adults: halo-effects outweigh rational choices

Research has shown that young children are selective in whom they trust, for example, learning selectively from more reliable sources. To explain what cognitive foundations this capacity may build upon, a recent dual-process account proposed that children recruit different kinds of cognitive strategies, including a) simple heuristics, e.g., favoring protagonists that are overall better or score high on a salient, accessible characteristic, and b) more systematic strategies, e.g., taking into account the protagonists’ individual properties. The present studies investigated the prediction that the more systematic processes require cognitive resources and develop with age. Children and adults were familiarized with two protagonists: The strong-and-shy protagonist scored high on a highly accessible trait (strength), whereas the weak-and-extraverted protagonist scored high on a less accessible trait (extraversion). In test trials, participants chose between these for strength- and extraversion-related tasks. The results were consistent with the prediction of the dual-process account: Older children, and adults under normal conditions, showed a pattern of systematic reasoning, selecting the protagonists with the relevant trait for a given task. Yet, younger children, and adults whose cognitive capacities were burdened with a secondary task, showed a pattern of heuristic reasoning, selecting the strong-and-shy protagonist for all kinds of tasks.