Connectome-wide Brain Signature During Fast Food Advertisement Exposure Predicts BMI At 2 Years.

Abstract

Food advertisements target adolescents contributing to weight gain and obesity. However, whether brain connectivity during those food advertisements can predict weight gain is unknown. Here, 121 adolescents (14.1±1.0y; 50.4% female; BMI: 23.4±4.8; 71.9% White) completed both a baseline fMRI paradigm viewing advertisements (unhealthy fast-food, healthier fast-food, and non-food) and an anthropometric assessment two years later. We used connectome-based predictive modeling (CPM) to derive brain networks that were associated with BMI both at baseline and the 2-year follow-up. During exposure to unhealthy fast-food commercials, we identified a brain network comprising high-degree nodes in the hippocampus, parahippocampal, and fusiform gyrus rich with connections to prefrontal and occipital nodes that predicted lower BMI at 2-year follow-up (r =0.17; p=0.031). A similar network was derived from baseline BMI (n=168; r =0.34; p<0.001). Functional connectivity networks during exposure to the healthier fast-food (p=0.152) and non-food commercials (p=0.117) were not significant predictors of 2-year BMI. Key brain regions in our derived networks have been previously shown to encode aspects of memory formation, visual processing, and self-control. As such, the integration of these regions may reflect a mechanism of adolescents' ability to exert self-control towards obesogenic food stimuli.