Project SummaryWhile the prevalence rates of pediatric obesity have plateaued in recent years, astaggering 35% of school age children remain classified as overweight or obese. Childrenfrom ethnic minority groups are at an even greater risk, with nearly 40% of Latino childrenso-classified by age 6. The physical and mental health risks and societal costs associatedwith pediatric obesity are well established. It is thus crucial for research efforts to focus onunderstanding early behavioral phenotypes that can explain individual variability inchildren’s regulation of energy balance and subsequent weight trajectory. Researchershave documented self-regulation (SR) and poor executive function (EF) as importantmechanisms for understanding the development of pediatric obesity, as well as its sharedco-morbidities with other mental health disorders (e.g., Attention-Deficit/HyperactivityDisorder [ADHD]). Poor executive function (EF), emotion regulation and reactivity (ER),and reward sensitivity (RS) have variously emerged as critical underlying processes interms of contributing to overeating and food preferences. However, there is a lack of 1)integration of these SR processes when examining weight outcomes, 2) longitudinalstudies, which are needed to disentangle whether potential SR deficits are risk factors forthe development of obesity or a consequence of it, 3) comprehensive measurement ofthese SR processes in terms of integrating behavioral measures, neuropsychological, andneurobiological markers, 4) studies examining the predictive association of SR processesas they relate to observed obesogenic mechanisms (e.g., SR of energy intake, healthy-habits) and 5) how environmental factors (e.g., parenting, home environment) cancontribute to and moderate the link between SR phenotypes and weight outcomes.Consistent with PAR-18-105, we leverage the ongoing data collection as part of awardR01MH112588 (PIs Graziano and Dick), which is measuring young children’s (ages 4 to6) SR processes (EF, ER, and RS) at a behavioral, neuropsychological, andneurobiological level using MRI. The proposed ancillary study (n = 288) examines how SRphenotypes predict obesogenic mechanisms and subsequent obesity-related trajectories.The proposed sample offers a unique opportunity to examine health outcomes within atypically understudied, yet high-risk population for obesity (i.e., Hispanic/Latino) along withinclusion of a clinical group (i.e., children with ADHD).