14 DAY TRIAL // They may look worse than a spider, but women suffering of anorexia see themselves as fat as a hippo. And there is more to this disease than just extreme weight loss: hair loss, dry skin and osteoporosis; nails stop growing and a feeling of being overwhelmed settles in. In women, menstruation turns irregular and can even disappear for months; menopause comes early and spontaneous abortions can occur. Colitis can develop and the metabolism is turned upside-down. About 10% of the anorexic women die because of an organic failure or other issues linked to anorexia (the highest rate of mortality amongst all mental disorders). At the moment, there's no treatment for anorexia.
But even a year after recovering from anorexia and maintaining a normal body weight, these women display a different brain activity model than non-anorexic women, as found by a team led by Dr. Walter H. Kaye, professor of psychiatry, University of Pittsburgh School of Medicine, and recently published in the American Journal of Psychiatry.
It appears that young women, worriers and perfectionists ever since childhood, are highly vulnerable to anorexia, and these behavioral patterns are strongly wired in their brains, being present even after recovery.
"Functional magnetic resonance imaging (fMRI) of the brain is providing new clues to why people with anorexia nervosa are able to deny themselves food and other immediately rewarding pleasures. In addition, we have a new understanding of why people with anorexia seem to worry so much," said Kaye.
The team investigated 13 former-anorexic women, having a normal weight and regular menstrual cycles for at least one year, and 13 healthy control women. The subjects had to guess if a flashing question mark on a computer screen was a number higher or lower than five. A march meant a $2 reward, wrong answer translated to $1 penalties.
Meanwhile, women's brain activity in the anterior ventral striatum (connected to instant emotional responses) and caudate (connecting actions to outcome and planning) nuclei were observed through fMRI brain imaging.
"During the game, brain regions lit up in different ways for women who formerly had anorexia compared to healthy controls. While the brain region for emotional responses showed strong differences for winning and losing in healthy women, women with a past history of anorexia showed little difference between winning and losing. For anorexics, then, perhaps is it difficult to appreciate immediate pleasure if it does not feel much different from a negative experience," said first author Dr. Angela Wagner from University of Pittsburgh School of Medicine.
"The caudate regions of the brains of formerly anorexic women, however, were more active than those of healthy controls, especially in the most anxious people, suggesting that women with a history of anorexia were more focused on the consequences of their choices. Anorexics tend to worry about the future and doing things right." said Kaye.
"There are some positive aspects to this kind of temperament. Paying attention to detail and making sure things are done as correctly as possible are constructive traits in careers such as medicine or engineering. Carried to extremes, however, such obsessive thinking can also be harmful," he added.
Normal women reacted to gaining and losing by "living in the moment" and waiting for the next task, while former-anorexics found it difficult to let it go.
"They tended to try and find strategies within the game, and were concerned about making mistakes. Increasing researchers' understanding of these basic brain differences could influence future development of drugs and other treatments for anorexia. We're starting to understand these processes because we have better tools, such as brain imaging, and a better understanding of how the brain works due to advances in cognitive neuroscience," said Kaye.