Anorexia is a habit, study says
People with anorexia nervosa choose choose low-fat, low-calorie food out of habit, a new study says. When they choose what to eat, they activate a part of the brain for habitual behavior, making it hard for them to quit.
The study was done by researchers at Columbia University Medical Center, New York State Psychiatric Institute, the Mortimer B. Zuckerman Mind Brain Behavior Institute, and New York University was published in Nature Neuroscience.
The researchers used functional magnetic resonance imaging–which tracks activity in the brain in real time–to monitor 21 women with anorexia nervosa and 21 healthy individuals while they made a series of choices about what food to eat.
Individuals with anorexia nervosa consistently chose fewer high-fat foods. The brain regions they used to make those choices were also different: for individuals with anorexia nervosa, choices about what to eat were associated with activation in the dorsal striatum, a brain region known to be related to habitual control of actions.
Furthermore, activation in fronto-striatal brain circuits during the experiment predicted how many calories they chose to consume in a meal the following day. These are the first data linking abnormalities in brain activity with the salient behavioral disturbance of anorexia nervosa, restrictive food choice.
These findings open up entirely new avenues for treatment development and understanding of disease mechanisms. “We are already developing a new psychotherapy intervention built on principles of habit reversal that helps patients with anorexia nervosa change maladaptive behaviors,” says Joanna Steinglass, MD, one of the lead authors and associate professor of clinical psychiatry at Columbia University Medical Center. “As we improve our understanding of brain mechanisms, new medication targets may emerge as well.”
