OXT and obesity disorder: These findings are in line with fMRI studies showing that in men with overweight and obesity, 24 IU of IN oxytocin reduced the blood oxygenation level-dependent (BOLD) signal in response to high-calorie food vs. non-food visual stimuli in the VTA [227], the origin of the mesolimbic dopaminergic reward system and a key hedonic brain region that drives efforts to obtain desired foods [32,228].