Social categories are often defined by the boundaries that they form between individuals. However, many social structures describe "complementary" relationships between individuals, defining both the power that we hold over others and our obligations to them and vice versa. In two studies conducted in the U.S., we investigated a sample…

The development of (early) numerical cognition builds on children's ability to understand and manipulate quantities and numbers. However, previous research did not find conclusive evidence on the role of symbolic and non-symbolic skills in the development of (early) numerical cognition. The aim of the current study was to clarify the relation…

Theory of Mind (ToM), the ability to attribute mental states to agents, has usually been measured with explicit verbal tasks and found to develop slowly during the preschool years. New implicit ToM measures have lately revolutionized the field by suggesting that ToM may be present much earlier in development. However, recent replication studies of…

Young children are remarkably compliant with social norms, especially those governing fairness and equality. Yet children also frequently observe and face opportunities to violate those social norms, particularly in situations in which doing so is self-beneficial. In 3 studies, we investigated the conditions under which children adhere to social…

Three experiments examined whether 4- and 5-year-olds can explicitly revise uncertain beliefs in light of disconfirming evidence. We considered 2 factors that might influence belief revision: (a) the type and variability of evidence provided, and (b) whether children generated an explanation of their initial hypothesis. When provided with limited…

Although action experience has been shown to enhance the development of spatial cognition, the mechanism underlying the effects of action is still unclear. The present research examined the role of visual cues generated during action in promoting infants' mental rotation. We sought to clarify the underlying mechanism by decoupling different…

These studies examined the role of ontological beliefs about category boundaries in early categorization. Study 1 found that preschool-age children (N = 48, aged 3-4 years old) have domain-specific beliefs about the meaning of category boundaries; children judged the boundaries of natural kind categories (animal species, human gender) as discrete…

In simple rule-switching tests, 3- and 4-year-olds can follow each of two sorting rules but sometimes make perseverative errors when switching. Older children make few errors but respond slowly when switching. These age-related changes might reflect the maturation of executive functions (e.g., inhibition). However, they might also reflect…

This study investigated the roles of different executive function (EF) components (inhibition, shifting, and working memory) in 2-step arithmetic word problem solving. A sample of 139 children aged 8 years old and regularly attending the 3rd grade of primary school were tested on 6 EF tasks measuring different EF components, a reading task and a…

Age-related differences in episodic memory judgments assessing recall of fact information and the source of this information were examined. The role of executive function (EF) in supporting early episodic memory ability was also explored. Four- and 6-year-old children were taught 10 novel facts from two different sources (experimenter or puppet),…

The current study examined the role of increased attentional load in 24 month-old children's multistep problem-solving behavior. Children solved an object-based nonspatial working-memory search task, to which a motor component of varying difficulty was added. Significant disruptions in search performance were observed with the introduction of the…

The aim of the present study was to investigate the role of executive functions (EF) in theory-of-mind (ToM) performance in deaf children and adolescents. Four groups of deaf children aged 7-16 years, with different language backgrounds at home and at school, that is, bilingually instructed native signers, oralist-instructed native signers, and…