Bulimia symptoms reduced with electrical brain stimulation
Bulimia nervosa, or simply bulimia, is both an eating disorder and mental health condition.
Bulimia is characterized by behaviors such as controlling weight by severely restricting the amount of food consumed, followed by binge eating and, lastly, forced vomiting to remove the food from the body. This vicious behavior cycle becomes compulsive over time and is similar to that of addiction.
Bulimia typically emerges in adolescence and is much more likely to develop in women. It is thought that 1-2 per cent of women have bulimia at some stage in their life. The disorder is associated with multiple medical complications and up to 4 per cent of people with bulimia die prematurely from the disorder.
Previous studies published by the Eating Disorders Research Group at King's found that repetitive transcranial magnetic stimulation (rTMS), already an approved treatment for depression in the US, was effective in reducing food craving in people with bulimia.
This new study examined the use of transcranial direct current stimulation (tDCS), a less expensive and more portable form of brain stimulation. tDCS uses electrodes placed on the head to stimulate specific parts of the brain, which could improve cognitive function in areas related to reward processing and self-control.
The study included two men and 37 women with bulimia who underwent 20-minute sessions of transcranial direct current stimulation to an area of the brain involved with reward processing and self-regulation. There was also one sham session where the electrode stimulation lasted only 30 seconds.
Participants then reported their desire to binge eat, fear of weight gain, general mood and frequency of bulimic behaviors in the 24 hours following treatment, the researchers said.
The patients reported a reduction in bulimia symptoms after brain stimulation.
"Our study suggests that a noninvasive brain stimulation technique suppresses the urge to binge eat and reduces the severity of other common symptoms in people with bulimia nervosa, at least temporarily," says Maria Kekic, first author of the study.
'Although these are modest, early findings, there is a clear improvement in symptoms and decision-making abilities following just one session of tDCS. With a larger sample and multiple sessions of treatment over a longer period of time, it is likely that the effects would be even stronger. This is something we're now looking to explore in future studies.'
The advantage of tDCS is that it’s much less expensive and more portable than other brain stimulation techniques, which raises the possibility of one day offering treatment that could be self-administered at home by patients with bulimia. This could either be as an addition to existing psychological therapies or as a standalone, alternative approach.