Functional magnetic resonance imaging of appetite and eating behaviour in obesity surgery. (360G-Wellcome-087745_Z_08_Z)

Appetite and eating behaviour changes after obesity surgery are poorly understood. It is likely that alterations in brain reward system play a key role in weight loss. By visualizing activity in brain food reward systems when viewing food pictures, using functional magnetic resonance imaging (fMRI), we will be able to demonstrate how brain activation related to food craving is altered by the 2 different surgical procedures. We will also examine whether baseline psychiatric, psychological and fM RI characteristics predict weight loss after surgery. Comparison will be made between obese patients who have previously undergone (i) gastric bypass and (ii) gastric banding surgery, and (iii) un-operated obese patients, and (iv) after temporary reversal of the anorexigenic gut hormone increases seen after gastric bypass surgery. In a prospective study, weight loss at one year post-surgery will be compared between patients with and without binge eating disorder and correlated with other bas eline psychological measurements and fMRI activation in brain food reward systems. Identifying the brain pathways through which obesity surgery works and understanding of the neuropsychological predictors of individual responses to obesity surgery, will aid the use and choice of surgery, and development of novel treatments for obesity, less invasive and risky than surgery.