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VI. EXECUTIVE CONTROL IN PRESCHOOLERS: NEW MODELS, NEW RESULTS, NEW IMPLICATIONS.

Executive control (EC) has gained increasing acceptance in developmental science as a central construct that helps to explain both normative age-related change and individual variation in learning and behavior. This popularity is not unfounded, given the utility of executive tasks in predicting individual differences across a range of important developmental domains, including internalizing and externalizing behavior; theory of mind; academic achievement; emotion regulation; and creativity, often over extended time intervals (Carlson & Moses, 2001; Carlson & Wang, 2007; Clark et al., 2010; Riggs, Jolley, & Simpson, 2013; Welsh et al., 2010). Despite these ubiquitous associations, consensus on the definition of EC continues to elude the field. This lack of clarity is especially evident for early childhood, where theoretical models derived from adult literature may not adequately reflect the dynamic nature of rapidly maturing neural and cognitive systems. In this volume, we tackled these challenges through the unique application of the bifactor model to data collected across the preschool age range. The bifactor approach provided an innovative means to address a central measurement issue in EC research: the inherent conflation of the specific control processes of interest with the foundational stimulusand This article is part of the issue “The Changing Nature of Executive Control in Preschool” Espy (Issue Editor). For a full listing of articles in this issue, see: http://onlinelibrary.wiley.com/doi/10.1111/mono. v81.4/issuetoc.