Longitudinal changes in brain structures related to appetitive reactivity and regulation across development.

In the United States over one-third of the population, including children and adolescents, are overweight or obese. Despite the prevalence of obesity, few studies have examined how food cravings and the ability to regulate them change throughout development. Here, we addressed this gap in knowledge by examining structural brain and behavioral changes associated with regulation of craving across development. In a longitudinal design, individuals ages 6-26 completed two structural scans as well as a behavioral task where they used a cognitive regulatory strategy to decrease the appetitive value of foods. Behaviorally, we found that the ability to regulate craving improved with age. Neurally, improvements in regulatory ability were associated with cortical thinning in medial and lateral prefrontal cortex. We also found that models with cortical thickness measurements and age chosen by a lasso-based variable selection method could predict an individual's regulation behavior better than age and other behavioral factors alone. Additionally, when controlling for age, smaller ventral striatal volumes were associated with higher body mass index and predicted greater increases in weight two years later. Taken together, these results demonstrate a role for structural brain changes in supporting the ability to resist cravings for appetitive foods across development.

Social influence shifts valuation of appetitive cues in early adolescence and adulthood.

Other people can profoundly affect one's opinions and decisions. In the current study, we compared the effects of peer influence on responses to a primary reward-food-in both young adolescents and adults. Food is critical for survival, and in addition to its rewarding properties, habits and practices surrounding eating are heavily influenced by social and cultural norms. To address the impact of peer influence on food valuations, young adolescents ages 10-14 and young adults ages 18-22 rated the desirability of foods before and after seeing peer opinions about those foods. We then compared the degree to which participants changed their ratings of food desirability as a function of the type of social information received (e.g., peers liking a food more or less than did the participant). We found that all participants' ratings conformed to the peer ratings and that adolescents had less stable valuations across all conditions over time. These results provide evidence for the effectiveness of peer influence in shifting valuations of appetitive stimuli and can inform interventions aimed at improving healthy eating choices. (PsycINFO Database Record (c) 2018 APA, all rights reserved).