Same areas of the brain are responsible for both conditions

May 22, 2012 13:27 GMT  ·  By
Obesity and anorexia are triggered by malfunctions in the brain's reward system
   Obesity and anorexia are triggered by malfunctions in the brain's reward system

In a paper published in the latest issue of the esteemed medical journal Neuropsychopharmacology, experts at the University of Colorado in Denver reveal that certain changes in a series of neural pathways can mean the difference between obesity and anorexia in women.

Experts with the UCD School of Medicine discovered that areas of the brain involved with coding for rewards are affected in both conditions. This reward circuitry is desensitized in obese women, but highly-sensitized in anorexic ones.

In addition, the team also found that the same dopamine pathways that are involved in drug addiction also play an important role in the development of eating disorders. Dopamine is a key neurotransmitter in the human brain, PsychCentral reports.

For this study, experts analyzed a number of 63 women, who were all enrolled in the Developmental Brain Research Program at the UCD-SM. Assistant professor Dr Guido Frank is the director of the program. He explains that all test subjects' brains were analyzed using a medical imaging technique.

Functional Magnetic Resonance Imaging (fMRI) works by analyzing the patterns in which blood flows through the brain. This enables scientists to figure out which neural pathways are associated when a certain stimuli is processed.

Results obtained from the 53 participants were then compared with fMRI readings from a series of healthy women who were considered to be of average weight. “It is clear that in humans the brain’s reward system helps to regulate food intake,” Frank explains.

“The specific role of these networks in eating disorders, such as anorexia nervosa and, conversely, obesity, remains unclear,” the team leader goes on to say. The new research is very important, given the current obesity epidemic.

In the United States alone, one third of the population is obese or morbidly obese, while two thirds are overweight. Only 33 percent of all American citizens are within normal weight limits for their height. This obesity epidemic is affecting most well-off countries, including France and the United Kingdom.