The prevalence of obesity has dramatically increased over the last 25 years. In the United States, it is estimated that two-thirds of the population is either overweight or obese. This increase will undoubtedly continue to have profound medical, economic, and psychosocial consequences. As obesity and its medical complications become more common, novel inter-disciplinary approaches are emerging to help understanding the complex regulation of eating behavior and body weight. Although the notion that the brain is critical in regulating food intake and body weight is becoming more commonly...