Bulimia Nervosa Research Discovers Brain Link.

In Brain Disorders, Brain General Structure and Function, Brain Science by Brainy Days Ahead

Brains of women with bulimia show decreased blood flow in the precuneus, a part of the brain associated with self-reflection, while women without bulimia showed increased blood flow in the precuneus. Natonal Medical Center and George Mason University researchers conducted the study involving 10 women wth bulumia and 10 women without the condition. The study is the first to explore the neural reactions to food cues following a stressful event in women with bulimia nervosa. First, all of the subjects came to a lab where they all ate the same meal. After about an hour, the subjects entered an MRI scanner where they viewed ordinary pictures of scenes or objects, and later, a series of pictures of high fat/high sugar foods such as ice cream and pizza.  Participants then were asked to complete an impossible math problem to create a stressful and possibly embarrasing reaction. The subjects then re-entered the scanner and looked at different photos of high fat/high sugar foods. After every activity in the scanner, the women rated their levels of stress and food cravings. All the subjects experienced increased stress after the stress task, and also reported that stress went down after seeing the food cues again. Furher, every time that participants saw the food cues, they reported that their craving for food went up. The surprise came when researchers examined the very different brain responses on their MRI scans. Researchers believe that the bulimic participants’ decreased blood flow in the brain’s precuneus suggests that the introduction of food shuts down self-critical thinking in bulimics and gives them something to focus on instead of the painful prospect of dealing with their own shortcomings. The research provides a neurobiological basis for the use of food as a distractor during periods of stress in women with bulimia.