Can the brain’s reward circuits fight anorexia?
Scientists are discovering how one of the most lethal psychiatric conditions, anorexia nervosa, develops and it seems that targeting the brain’s reward pathways can kick off the survival instinct.
In 10 seconds? Anorexia tricks sufferers to starve themselves. Research show that childhood immune diseases boost the risk of its development by 36%. However, tweaking the brain’s reward system can turn on the drive to eat. (Read the science)
Why don’t patients with anorexia crave food? Part of the answer lies in how the brain circuitry controlling energy levels interacts with the sense of reward that comes with eating. Anorexia sufferers don’t feel this “reward” and their nervous system suppresses their urge to survive, which can explain the lack of hunger. (Read more about the neurobiology of anorexia)
How come we have such a vague understanding of anorexia? Ethical concerns limit the involvement of live human subjects to study the brain circuits where this debilitating condition is formed. As an alternative, scientists are studying the brain’s reward system underpinning anorexia using an activity-based anorexia model in rodents. (Read more here)
And what have we learnt from it? We know that the release of dopamine, a neurotransmitter in the brain, is responsible for the sense of pleasure. Addictive drugs, for example, hijack this function. Anorexia sufferers, on the other hand, become unable to derive pleasure from eating. Researchers are now able to selectively switch neural circuits on or off and activate the pathway that boosts the feeling of reward. This suppresses anorexia and prevents extreme weight loss in rodents. (Learn more)
Will this lead to a cure for humans? Hopefully. Currently there is no effective treatment to this life-threatening condition. Societal pressure about body image, a lack of understanding from large sections of the public and the proliferation of online communities encouraging starvation and extreme weight loss poses an additional danger.
Are some people especially vulnerable? A recent study of 930,977 Danish children has found that autoimmune and autoinflammatory diseases significantly increased the risk of anorexia, so more knowledge of immune system disturbances could lead to new treatments.
So what is being done to protect young people? Fortunately, national health services and counselling organisations can help mitigate these harmful messages. France has gone as far as punishing people running pro-anorexia websites with fines and prison sentences.
How is anorexia nervosa treated?
It's notoriously difficult and complex task involving doctors, mental health professionals and dietitians. New approaches focus on the positive involvement of families to help teenage sufferers.
Previously professionals blamed controlling parents for the development of anorexia, but lately they have been empowering them to help with the treatment of their children, by helping them to understand the impact of brain circuit dysfunction.
Clinicians however stress that there are no one-size-fits-all therapies.
This research was curated by
Claire Foldi, PhD, Postdoctoral Fellow at Monash University, Melbourne, specialising in neurobiological mechanisms that underlie psychiatric disease.
(Psst, Claire distilled 19 research papers to save you 624.8 min)
