 In this sub-study we want to unravel the exact mechanism and provide more information about the efficacy of the BaroSense ACETM Stapler. Therefore we will measure changes in various parameters that are known to affect weight loss and metabolism, before and after gastric plication by using the BaroSense ACETM Stapler in overweight subjects these parameters will only be measured in patients at MUMC. These parameters are post-prandial satiety, food-reward and related brain signalling, gastric emptying, behaviour towards food, food intake, satiety hormone release, microbiota composition and inflammatory markers. 