The impact of executive function on reward processing in children: neural correlates and individual differences.

University of Minnesota Ph.D. dissertation. September 2011. Major: Child Psychology. Advisor: Kathleen M. Thomas. 1 computer file (PDF); vii, 135 pages, appendix p. 113-135Executive function (EF) involves the integration of cognitive processes in order to support and sustain goal-directed behaviors that are crucial in the development of behavioral regulation (Sergeant, Geurts, & Oosterlaan, 2002). Motivational and rewarding information may alter the underlying cognitive processes surrounding the implementation of these goal-directed behaviors. Previous research indicates that both behavior and brain systems associated with reward and executive function (EF) processes may be interacting in children with ADHD (Luman, Van Meel, Oosterlaan, Sergeant, & Geurts, 2009b; Scheres, Milham, Knutson, & Castellanos, 2007). However, little research has been conducted within middle childhood to explore the intersection of EF and reward processing in typical development. Furthermore, little is know about the degree to which reward processing may be interacting with low EF ability on a behavioral and neural level during middle childhood. The current study examined behavioral performance as well as functional and structural Magnetic Resonance Imaging (MRI) data to address the degree to which executive function (EF) ability may be related to reward processing behaviors and brain circuitry in middle childhood. Chapter 2 addresses the overlap of EF and reward processing in behavioral task performance and parent questionnaire measures. Chapter 3 describes brain activation pattern differences in children with high versus low EF ability in a reward processing task. This portion of the study was conducted to determine whether children with lower EF ability process reward information similarly to children with high EF ability. In Chapter 4, the links between behavioral performance on EF and reward processing measures and structural volumes of related brain areas are discussed. Finally, in Chapter 5, general conclusions, limitations and future directions are outlined