Although the research isn't that new, there was a wonderful write-up on Walt Kaye's brain imaging research in the Psychiatric Times (creatively titled Anorexia and Brain Imaging).
A short excerpt:
...insights into the ventral (limbic) and dorsal (cognitive) neural circuit dysfunction, perhaps related to altered serotonin and dopamine (DA) metabolism, may help explain why individuals with anorexia often report that dieting reduces their anxiety while eating increases it and why they worry about long-term consequences but seem impervious to immediate gratification and unable to live in the moment.The article isn't simple--the magazine is aimed at psychiatrists, not otherwise clueless neuroscience geeks like yours truly--but it's written very clearly, and Google helped me figure out what terms I didn't know. If you ever want a good handout on up-to-date information on anorexia for medical professionals, this would be a good one to print and keep on hand.
Many women diet in this culture, but relatively few (0.5%) have anorexia, Kaye told Psychiatric Times. “Why is that? Well, you pretty much have to have a certain temperament and personality in childhood to be vulnerable for . . . an eating disorder,” said Kaye. “Not everyone who develops anorexia has all these traits in childhood, but most have one or more of them,” he said. “These traits include harm avoidance, anxiety, behavioral inhibition, difficulty with set shifting [easily moving from one mental set to another], a tendency to focus on details rather than the big picture, and perfectionism.” Even after recovery, these personality and temperament traits persist, pointing to underlying neurobiological factors.
...Kaye said that evidence from imaging studies suggests that disturbances in the serotonergic system might contribute to vulnerability for restricted eating and behavioral inhibition as well as a bias toward anxiety, particularly excessive concern with consequences. Meanwhile, DA dysfunction, particularly in striatal circuits, may contribute to altered reward, decision making, stereotypic motor movements, and decreased food ingestion.