Development and organization of executive functions in 4-to 11 year-old children: A factor study.

Executive functioning (EF) is an umbrella term used to refer to the higher-order cognitive processes whose principal function is to facilitate the adaptation of an individual to new and non-routine situations. In the present study, inhibition, mental flexibility, and working memory were assessed through 6 executive tasks administered to 329 children aged from 4 to 11 years, in order to examine the development and organization of executive functioning in both early and middle childhood. Results reveal specific developmental trends for each component, with a period of rapid general development during the preschool period. Confirmatory factor analyses were used to examine the organization of EF in our sample. First, the poorness of fit of the unitary model was found for both groups, confirming the fractionated nature of EF in preschoolers as well as in older children. Second, the analyses confirmed the adequacy of the fit of the three-dimensional model (i.e., inhibition, flexibility, and working memory), while also indicating that other specific two-dimensional models gave reasonable fits to the data from both age groups. The factor structure obtained supports both the unitary and diversity nature of the executive organisation during early and middle childhood. Furthermore, our data suggest a progressive differentiation of executive processes (in particular flexibility and working memory) in the course of development.