In many cultural contexts, judging another as conscious or not has profound practical, legal, and philosophical consequences. However, little research focuses on how our ability to make such judgements arises. Thirty years ago a classic set of studies by Flavell et al. demonstrated that children do not develop a complex understanding of conscious…

The ability to consider multiple possibilities forms the basis for a wide variety of human-unique cognitive capacities. When does this skill develop? Previous studies have narrowly focused on children's ability to prepare for incompatible future outcomes. Here, we investigate this capacity in a causal learning context. Adults (N = 109) and 18- to…

Piaget's theory of stage structure is synonymous with discussions involving cognitive development. As with any theoretical model, researchers inevitably and rightly seek to affirm and/or contest the elements of the model presented. In this comparative study, students' performance across three hands-on engineering tasks for two distinct student…

Cognitive development of eighth-grade students, as identified by Jean Piaget, occurs during a time when many of them are transitioning between concrete operations and formal operations where the ability to think in abstract concepts becomes possible. Because of this period of transition, many eighth-grade students find difficulty in demonstrating…

A good deal of research purports that bilingualism has a positive effect on some aspects of cognitive functioning. However, this effect is not consistent, and little research examines trajectories of cognitive skill development in bilingual children. Moreover, it remains unclear whether different types of bilingualism impact how cognitive…

According to Lev S. Vygotsky (1896-1934), the highest levels of abstract thinking and self-regulation in preschool development are established in "pretend play using object substitutions." An extensive research literature supports Vygotsky's empirical model of the internalization of self-guiding speech (social speech > private speech…