Multimodal Evidence for Neurocognitive Alterations in Pediatric Obesity

Abstract

Pediatric obesity is increasing in prevalence and severity in the United States, with one in five adolescents meeting criteria for overweight (body mass index; BMI for age and sex >85th percentile) and one in three meeting criteria for obesity (BMI for age and sex >95th percentile). Eight percent of adolescents have severe obesity (BMI for age and sex > 120% above the 95th percentile). Obesity is associated with a host of consequences for every organ system, including cardiovascular disease, endocrine disruption, and marked differences in neurocognition. Cognitive deficits in domains such as reward processing may be both cause and consequence of obesogenic behaviors. The underlying structural and functional brain differences, however, are not well understood in adolescents. This understanding is important since adolescents are in a developmental period vulnerable to risk-taking and negative outcomes for health, cognition, and adaptive functioning. The three studies in this dissertation sought to 1) characterize how severe obesity and bariatric surgery affect structural properties of the brain, 2) explore obesity’s effects on reward in the brain across a range of BMIs and at the level of severe obesity, and probe the brain-eating behavior relationship, and 3) relate alterations in neural connectivity and activation to behavioral measures of reward-related decision-making.