ABSTRACT
One of the main constraints of our cognitive functioning is the limited capacity of working memory. Because working memory is the system devoted to the active maintenance of information while processing is running, any limitation of its capacity has a direct impact on the amount of information that can be processed, and thus on the complexity of the situations we can deal with. As a consequence, it has often been argued that the poor performance frequently exhibited by young children in complex cognitive tasks resulted at least in part from a limited working memory capacity, whose age-related increase would constitute one of the main factors of cognitive development. This was one of the main assumptions of theories of cognitive development known as neoPiagetian theories such as Pascual-Leone (1970), Case (1985, 1992), or Halford (1982, 1993). Even if, as it appeared in the fi rst part of this book, these theories propose different accounts of the way cognitive resources increase with age, they all agree that there is an age-related increase in working memory capacity. Accordingly, it has repeatedly been shown that performance on complex span tasks designed to assess working memory capacity strongly increases with age (Case, Kurland, & Goldberg, 1982; Gathercole, Pickering, Ambridge, & Wearing, 2004) and is related to high-level cognitive performance and academic achievement in children and adolescents, lending strong support to the idea that working memory plays a major role in cognitive development. However, despite a great variety of empirical approaches and theoretical models of adults’ working memory, and although an extensive body of research has been devoted to working memory in children, Towse, Hitch, and Horton (2007) noted in their recent survey of the literature that it is not easy to discern a developmental model of working memory. The aim of this chapter is not to provide such a model, but more modestly to suggest some factors that could account for working memory development, and as a consequence for cognitive development. In these last years, our developmental investigations were conducted within the theoretical framework provided by our Time-Based Resource-Sharing model (TBRS, Barrouillet, Bernardin, & Camos, 2004). Though this model was mainly developed and tested in adults, it was initially inspired by unanticipated developmental phenomena (Barrouillet & Camos, 2001). In the following, we shall present the TBRS model, the main factors
that determine working memory capacity within this theoretical framework, and recent developmental studies that tested the impact of these factors on working memory development.
