Reward Mechanisms And Obesity

The physiological role of food intake is to maintain the body’s energybalance. Palatable food (i.e.“delicious" food), with its hedonic affection generatedthrough brain reward system, can affect the feeding behavior. The so-called rewardsystem is the system in the brain that produces pleasure. Overeating induced by thereward system is usually far beyond the body’s energy needs, and therefore isconsidered to be the main reason for the rapid spread of obesity epidemic in modernsociety. Compared with the homeostatic regulation mechanism, little is knownabout the affection of hedonic mechanism on eating behavior. And very similar todrug addiction, the excessive intake of food can also trigger the neural adaptation.In addition, the same congenital changes in the brain reward system, can at thesame time increase both the tendencies of drug addiction and obesity. Here thestudies on brain circuits that regulate the hedonic feeding behavior and their resultswere reviewed. And evidences of obesity and drug addiction having commonneural pathway mechanisms were also cited.