Effect of Adolescent Bariatric Surgery on the Brain and Cognition: A Pilot Study

OBJECTIVE: Neurocognitive deficits in pediatric obesity relate to poor developmental outcomes. We sought preliminary evidence for changes in brain and cognitive functioning relevant to obesogenic behavior following vertical sleeve gastrectomy (VSG) in adolescents relative to wait-listed (WL) and healthy (HC) controls. METHODS: Thirty-six adolescents underwent fMRI twice 4 months apart, during executive, reward, and episodic memory encoding, in addition to behavioral testing for reward-related decision making. RESULTS: VSG adolescents lost weight, while WL gained weight and HC did not change between timepoints. Gains in executive and reward-related performance were larger in VSG than control groups. Group x Time interaction (p <0.05 corrected) in left prefrontal cortex during N-back showed greater pre-surgical activation and post-surgical reduction comparable to HC levels, but increased in WL between timepoints. Similarly, left striatal parametric response to reward value reduced after surgery to HC levels; WL did not change. Memory-related medial temporal activation did not change in any group. CONCLUSION: Results provide pilot evidence for functional brain changes induced by VSG in adolescents with severe obesity. Weight loss and gain was paralleled by reduced and increased prefrontal activation, respectively, suggesting neural plasticity related to metabolic change.