Can neuroimaging explain the underlying mechanisms of overeating when comparing obese to lean subjects?

Abstract

Obesity is a condition caused by overeating, to a state were a person’s weight is not proportional to his or her length anymore. The concept of overeating is not completely solved. Many researchers have tried to unravel the underlying mechanism that causes overeating using Positron Emission Tomography (PET) or functional Magnetic Resonance Imaging (fMRI). Different research groups have used neuroimaging as a tool to come up with a piece of the story and they tend to agree that their answer is only part of the solution. Abnormal activation of brain areas of an obese person in response to eating is often in regions that are connected to emotion, control of behavior and reward. Important areas are the prefrontal cortex, dorsal insula, hippocampus, limbic/ paralimbic areas, amygdala and a reduced amount of dopamine D2 receptors in the striatum. The role of hormones is not taken into account in this paper, but is also important for understanding overeating. The real mechanism is complex and more studies have to be done. Neuroimaging can be used to do further research.