The developmental path of the distinctiveness heuristic in children

The primary aim of this study was to document the developmental course of distinctiveness effects throughout childhood. Specifically, we examined whether the reduction in false recognition rates that is traditionally observed in children after distinctive encoding could be explained not only by enhanced discrimination between studied and new items but also by the implementation of a conservative response criterion resulting from the use of metacognitive expectations about the quality of memories (i.e., distinctiveness heuristic). Two experiments were conducted in which children aged 4–5, 6–7, and 8–9 years old were asked to study a set of items presented either in pictorial (distinctive) or in word (less distinctive) form. In Experiment 1, pictures and words were displayed in two separate lists, a design that is supposed to favour reliance on the distinctiveness heuristic. In Experiment 2, the two types of stimuli were presented within the same list, a design that is supposed to make using the metacognitive heuristic ineffective. Overall, Experiments 1 and 2 provide evidence that children as young as 4 rely on the distinctiveness heuristic to guide their memory decisions, resulting in a reduction in the false recognition rate when items are presented using a pure-list design (Experiment 1), but not when they are presented using a mixed-list design (Experiment 2). The implications of these findings for our understanding of the development of metacognition and the involvement of metacognitive skills in children’s memory performance are discussed.