A prefrontal control system that is less mature than the limbic reward system in adolescence is thought to impede self-regulatory abilities, which could contribute to poor dietary choices and obesity. We, therefore, aimed to examine whether structural morphology of the prefrontal cortex and the amygdala are associated with dietary decisions and obesity in children and adolescents. Seventy-one individuals between the ages of 8–22 years participated in this study; each participant completed a computer-based food choice task and a T1- and T2-weighted (...) structural brain scans. Two indices of obesity were assessed, including age- and sex-specific body mass index and waist-to-height ratio. The behavioral task included rating 60 food stimuli for tastiness, healthiness, and liking. Based on each participant’s self-ratings, 100 binary food choices were then made utilizing a computer mouse. Dietary “self-control” was calculated as the proportion of trials where the individual chose the healthier food item over the total number of trials. Cortical thickness and amygdala subnuclei volumes were quantified using FreeSurfer 6.0 and CIT168 atlas, respectively. We found that WHtR was negatively associated with the thickness of bilateral superior frontal, left superior temporal, right insula, and right inferior temporal regions. We also found WHtR to be positively associated with the volume of the central nucleus region of the amygdala, after adjusting for the hemisphere, age, sex, and intracranial volumes. A similar data pattern was observed when BMIz was used. Moreover, we found that across all participants, thinner right superior frontal cortex and larger left CEN volumes predicted lower dietary self-control. These results suggest that differential development of the PFC and amygdala relate to obesity and dietary self-control. Further longitudinal studies are merited to determine causal relationships among altered PFC to amygdala neural circuitry, dietary self-control, and obesity. (shrink)

Food choices are a key determinant of dietary intake, with brain regions, such as the mesolimbic and prefrontal cortex maturing at differential rates into adulthood. More needs to be understood about developmental changes in healthy and unhealthy food perceptions and preference. We investigated how food perceptions and preference vary as a function of age and how food attributes impact age-related changes. One hundred thirty-nine participants completed computerized tasks to rate high-calorie and low-calorie food cues for taste, health, and liking, followed (...) by 100 binary food choices based on each participant’s ratings. Dietary self-control was considered successful when the healthier food was chosen. Self-control success ratio was the proportion of success trials over total number of choices. Beta-weights for health and taste were calculated as each attribute’s influence on food preference. Adiposity measurements included BMI z-score and waist-to-height ratio. High-calorie foods were rated more tasty and less healthy with increasing age. Older participants liked high-calorie foods more, and β-taste was associated with age. Significant age-by-WHtR interactions were observed for health and taste ratings of high-calorie foods, β-taste, and marginally for preference of high-calorie foods. Stratifying by WHtR, we found age-related increases in taste and preference ratings of high-calorie foods in the high WHtR group alone. In contrast, age-related decreases in health ratings of high-calorie foods were significant in the low WHtR group alone. Age and β-taste were significantly associated in the high WHtR group and only marginally significant with low WHtR. Although participants rated low-calorie foods as less tasty and less healthy with increasing age, there was no association between age and preference for low-calorie foods. Participants made faster food choices with increasing age regardless of WHtR, with a significant age-by-WHtR interaction on reaction time. There were no age-related effects in self-control success ratio and β-health. These results suggest that individual differences in age and central adiposity play an important role in preference for high-calorie foods, and a higher importance of food tastiness in food choice may contribute to greater preference for high-calorie foods with increasing age. (shrink)