Place value concepts were measured longitudinally from kindergarten (2017) to first grade (2018) in a diverse sample (n = 279; M[subscript age] = 5.76 years, SD = 0.55; 135 females; 41% Black, 38% White, 8% Asian, 12% Latino). Children completed three syntactic tasks that required an explicit understanding of base-10 symbols and three approximate…

Three hundred and forty-one children (M[subscript age] = 9,0 years) engaged in a series of science tasks in collaborative, same-sex pairs or did not interact. All children who collaborated on the science tasks advanced in basic-level understanding of the relevant task (motion down an incline). However, only boys advanced in their conceptual…

Advanced theory-of-mind (AToM) development was investigated in three separate studies involving 82, 466, and 402 elementary school children (8-, 9-, and 10-year-olds). Rasch and factor analyses assessed whether common conceptual development underlies higher-order false-belief understanding, social understanding, emotion recognition, and…

Category-based induction is a hallmark of mature cognition; however, little is known about its origins. This study evaluated the hypothesis that category-based induction is related to semantic development. Computational studies suggest that early on there is little differentiation among concepts, but learning and development lead to increased…

Existing evidence suggests that children, when they first pass standard theory-of-mind tasks, still fail to understand the essential aspectuality of beliefs and other propositional attitudes: such attitudes refer to objects only under specific aspects. Oedipus, for example, believes Yocaste (his mother) is beautiful, but this does not imply that…

Fundamental to amassing a lexicon of relational terms (i.e., verbs, prepositions) is the ability to abstract and categorize spatial relations such as a figure (e.g., "boy") moving along a path (e.g., "around" the barn). Three studies examine how infants learn to categorize path over changes in "manner," or how an action is performed (e.g., running…

Executive function mechanisms underpinning language-related effects on theory of mind understanding were examined in a sample of 165 preschoolers. Verbal labels were manipulated to identify relevant perspectives on an explicit false belief task. In Experiment 1 with 4-year-olds (N = 74), false belief reasoning was superior in the fully and…

This study investigated preschoolers' living kinds conceptualization by employing an extensive stimulus set and alternate indices of understanding. Thirty-four 3- to 5-year-olds and 36 adult undergraduates completed 3 testing phases involving 4 object classes: plants, animals, mobile, and immobile artifacts. The phases involved inquiries…

There is ongoing debate about children's ability to use subsequently acquired language to describe preverbal experiences. This issue was addressed experimentally in this investigation using a novel paradigm. Two-year-old children who lacked color words were individually taught to activate a bubble machine by selecting a particular color of bubble…

In order to investigate the relationship between the development of justice (moral) conceptions and the development of mathematical and physical (logical) conceptions, 50 children(ages 4-8) were administered a "positive justice" interview and five of Piaget's concrete-operational mathematical and physical tasks. (Author/CS)