According to an article published in the January 2009
issue of the Archives of General Psychiatry
, women with bulimia
, when compared with healthy women, show different patterns of brain activity while doing a task that requires self-regulation. This abnormality may underlie binge eating and other impulsive behaviors associated with eating disorders.
In the first study of its kind, Rachel Marsh, Ph.D., Columbia University
, and her colleagues assessed self-regulatory brain processes in women with bulimia without using disorder-specific cues, like pictures of food.
In Marsh's study, 20 women with bulimia and 20 healthy controls watched a series of arrows on a computer screen and were asked to identify the direction in which the arrows were pointing while the researchers observed their brain activity using functional magnetic resonance imaging.
Most people easily complete similar tasks when the direction of the arrow matches the side of the screen it is on—an arrow on the left side pointing to the left—but react more slowly and with more mistakes when the two don't match. To adjust, healthy adults activate self-regulatory processes in their brains to prevent automatic responses and increase focus on resolving the conflicting information.
Women with bulimia, however, become more impulsive during the task, respond faster and make more mistakes when presented with conflicting information.
Brain activity patterns also differ between the two groups. When answering correctly to conflicting information, women with bulimia show less activity in brain areas involved in self-regulation than healthy controls. Women with the most severe cases of the disorder show the least amount of self-regulatory brain activity and make the most errors on the task.
Marsh's research indicates that altered patterns of brain activity underlies impaired self-regulation and impulse control problems in women with bulimia and may help researchers develop better treatment approaches.
Dr. Marsh and her colleagues are now conducting additional studies on brain function in teens with bulimia, searching for indicators of the beginnings of the illness. They also recommend studying people in remission from an eating disorder. Comparison studies with impulsive people who have healthy weight and eating habits could also provide more information about which patterns of brain activity are most directly related to eating disorders.