Neural Mechanisms for Appetitive Responses to High Reward Foods

The investigators have previously combined functional magnetic resonance imaging (fMRI) with hormonal and behavioral assessments to better understand the impacts of glucose and fructose on appetite and its central regulation in humans and have made important observations in lean individuals linking fructose consumption to overeating and obesity. The investigators now propose to expand this work by examining the impacts of glucose and fructose ingested together (sucrose), as occurs in real life, and by examining effects of a common non-nutritive sweetener, sucralose, on brain and appetitive response. The investigators propose a random-order crossover design to determine the effects of caloric and non-nutritive sweeteners among lean, overweight, and obese participants. The investigators will measure circulating levels of hormones involved in satiety signaling, quantify food intake, and measure brain activity using blood-oxygen level dependent and arterial spin labeling methods and functional connectivity analyses.