In this commentary, I reflect from a neurocognitive perspective on the four chapters on natural number development included in this section. These chapters show that the development of seemingly basic number processing is much more complex than is often portrayed in neurocognitive research. The chapters collectively illustrate that children's…

Discusses when one can infer children's use of a rule, the mechanisms underlying the development of rule use, and the relation between understanding and execution. Contrasts relational complexity theory with cognitive complexity and control theory. (Author/KB)

Examines one preschooler's conversation with author to determine what concepts educators consider "difficult" for this age group. Finds that concepts such as "infinity" and "negative numbers," typically avoided by primary educators, were brought into view in the task-based conversations. Argues that individual…

Extends dynamic model of cognitive growth proposed by van Geert in three directions: (1) added a term to consider exposure to material to be learned; (2) developed method to apply model to cross-sectional studies; and (3) developed procedure to scale cognitive abilities tests with items of varying difficulty. Tests model with 2- to 15-year-olds'…