CRI听力:High Frequency Magnetic Stimulation to Cure Anorexia Vervosa

The sound you hear is from repetitive transcranial magnetic stimulation, or rTMS.

Put simply it's a high frequency magnetic field that is sent through the skull. A twitch in the fingers of a student volunteer shows that the target part of the brain is being reached. These connections are vital for reaching a special part of the brain, which controls the experience of craving, an important trigger for bingeing.

Kat Damezer was at school doing exams when she became anorexic. During a family holiday to Tibet she caught a virus and became very ill, losing a considerable amount of weight. She remembers how serious the illness was.

"I saw my spine in the mirror and was quite scared because I could see all the bones protruding. That was the only point when I thought, oh it doesn't look too good. Apart from that I knew I wasn't attractive to other people, but it was unacceptable for me to look any other way really."

Doctors say anorexics are the greatest danger to themselves. They are intensely controlled, focused and able to use many deceptions to cover the fact that they're not eating.

Professor Ulrike Schmidt is leading investigations into potential treatments at the Institute of Psychiatry and she believes anorexia has a long history reaching back to the middle ages.

According to Schmidt anorexia is extremely difficult to treat with psychotherapy. She says early treatment is vital because the behavior becomes more entrenched which is why suicide rates among anorexics are high.

"Sufferers are totally consumed by thoughts of food, fear of food and avoiding food. It stops them sleeping, it preoccupies all their waking hours and they constantly try to resist it because they're so terrified. They, typically after a period of time, have lots of physical disabilities, the bones crumble, osteoporosis develops, people have problems with all their internal organs. When you have anorexia nervosa you stop menstruating because you can't have children if you are acutely underweight."

Dr Frederique Van den Eynde is part of a team which is investigating whether rTMS stimulation may one day be used to treat people with eating disorders, particularly anorexia nervosa.

Any systematic treatment is a long way off, but Van den Eynde says they're making progress.

"We found that one session of Trans Cranial Magnetic Stimulation as we deliver it may reduce craving in people with bulimia nervosa, food cravings. In people with anorexia nervosa we found that this increases their sense of fullness and fatness when they're exposed to foods and also it reduces their anxiety."

This sort of brain stimulation is already being used to treat depression, but it's not yet an accepted therapy for food disorders.

For CRI, I am Li Dong.