Wednesday, January 7, 2009

Neurocircuitry in bulimics

New research in an article on the brain differences in bulimics appears in the January issue of the Archives of General Psychiatry. The study consisted of 40 participants (20 with bulimia who had a median duration of illness of nine years and 20 healthy controls). While undergoing functional magnetic resonance imaging, participants were shown pictures with arrows pointing left and right and were asked to identify which direction the arrows were pointing, regardless of where the arrows were on the screen. This is also known as the Simon Spatial Incompatibility Task.

The results showed the bulimics were faster but less accurate on more difficult trials which indicated impulsivity and less self-regulatory control. During correct trials, those with bulimia had less activity in their frontostriatal region than healthy controls. In incorrect responses, bulimics activated the dorsal anterior cingulate cortex more often. This contrasted from the healthy controls who activated the anterior cingulate cortex while responding correctly more and the striatum during incorrect responses.

The importance of researching the frontostriatal region of the brain is because it regulates both serotonin and dopamine. Research has often implicated serotonin and bulimia, but dopamine hasn't been studied as frequently.

The other interesting question this brings up is what Daniel le Grange, author of the new book Help Your Teen Beat an Eating Disorder asks, "
Does the abnormality occur because someone has bulimia nervosa, or does it contribute to developing it?"

This reminds me of the chicken and egg syndrome which invariably can be different for everyone. Depression and eating disorders is often used as an example. Some will say it was the depression that set off their eating disorder, while others say it was vice versa. I don't know if there is one right answer. But what I do think is that the perceptibility to an eating disorder already exists, whether through genetics or neurocircuitry, and perhaps through engaging in more disorderedness, the brain further changes. I could be completely wrong though too and maybe it's just rewiring from the beginning. More research is already underway looking at adolescent brains whose onset of illness is of less duration than those in this particular study.

6 comments:

Minh said...

Struggling with an eating disorder can cause profound isolation, fear and hopelessness. Because this illness thrives in secret, people with anorexia, bulimia and compulsive overeating hide their behaviours from those closest to them, hoping that no one will notice whilst hoping that someone will.
In order to begin the process of recovery, secrecy must give way to self awareness and honesty, and this can only happen in a safe, structured and caring environment.
Life Works, a UK based treatment centre, is the perfect place to start the process of your recovery.
By contacting Life Works, for a free initial assessment, you can speak with a counsellor that will help you best determine which type of treatment will work best for you.

http://www.lifeworkscommunity.com

Kim said...

I think about this chicken-or-the-egg thing quite a bit, so I enjoyed this post. I believe that I am genetically predisposed to anorexia, and that's it. Yes, it developed at a time of my life when I was particularly anxious/depressed (as I am predisposed to these too), but lots of people have those phases and don't develop eds. I think once you're into the disorder, then the anxiety or depression is compounded more and more, so it's really tough to tell up from down. I know I've felt best (depression and anxiety-wise) when I was at my healthiest weight, so that says something. That's a big motivator for me to get healthier. I don't like feeling down!

Lola Snow said...

I find this whole concept a bit weird when I try and apply it to myself. I have mostly been Bulimic (Impulsive) but also been through long periods of restrictive anorexia (not impulsive). I've also been a purging anorexic and god knows where that comes???

I'd be very curious to see how I scored on this test, and whether I scored differently when practicing different ED behaviours....

Lola x

Tiptoe said...

Kim, I agree that when in the throes of an ED, everything is compounded much more. The incentive to feel better when you're weight is more stable is important. You can get there!

Lola, Good point. This study doesn't talk about any crossover in Ed behaviors, but it would be interesting to see if the outcomes were the same or different.

karen said...

i have tried councelling for a long time, that did not work, i know im not in controll any more, everyday i am sick, im loosing my battle with this eating disorder. im scared

Tiptoe said...

Karen, I'm sorry you are having so much trouble. EDs do take such a toll on our bodies and minds. I encourage you to seek treatment. I don't know your history, but there are other practitioners out there that can be of help. I hope you find the help you need. We all deserve it.