A device that detects food craving-related activity in a key region of the brain and responds with electrical stimulation has shown promise in pilot clinical trial in two patients with loss-of-control binge eating disorder (BED).
In the trial, researchers at Perelman School of Medicine at the University of Pennsylvania followed two patients for six months, during which time the implanted device monitored activity in the nucleus accumbens region of the brain.
This area is involved in processing pleasure and rewards and has been linked to addiction.
Whenever the device sensed signals that had been found to predict food cravings in previous studies, it automatically stimulated that region to disrupt the craving-related signal.
The research found that over six months, the patients reported fewer binge episodes and also lost weight.
Study senior author Casey Halpern, MD, an associate professor of Neurosurgery and chief of Stereotactic and Functional Neurosurgery at Penn Medicine and the Corporal Michael J. Crescenz Veterans Affairs Medical Center, said:
“This was an early feasibility study in which we were primarily assessing safety, but certainly the robust clinical benefits these patients reported to us are really impressive and exciting.”
BED is typically associated with obesity and features frequent binge-eating episodes without the purging of bulimia.
The affected individual has a sense of loss of control over their eating habits, continuing to eat beyond the usual point of feeling sated.
A 2018 study with experiments on mice and humans found evidence that low-frequency electrical activity arises in the nucleus accumbens just before cravings but not before normal, non-binge eating.
The researchers stimulated the nucleus accumbens in mice to disrupt this activity and learned that the mice ate significantly less of a tasty, high-calorie food they otherwise would have gorged themselves upon.
The device the team used to record signals from and stimulate the brains of the mice is widely used and approved for the treatment of drug-resistant epilepsy.
The device is surgically placed beneath the scalp, with wires running through the skull to the nucleus accumbens in each hemisphere of the brain.
In the new study, Halpern’s team fitted two severely obese BED patients with the brain-stimulation devices and recorded signals from the devices for six months.
Sometimes, the patients were in the laboratory, where they were presented with buffets of their favourite foods, with fast-food and sweets among the more common items.
But the patients were mostly at home going about their daily routines.
The scientists observed that a distinctive low-frequency signal in the nucleus accumbens appeared in the seconds before the patients’ first bites of their binge meals – just like in their prior study,
In the next phase, the brain-stimulation devices automatically delivered high-frequency electrical stimulation to the target region whenever the low-frequency craving-associated signals occurred.
During this six-month period, the patients reported sharp reductions in feelings of loss-of-control, and in the frequencies of their bingeing episodes—each also lost more than 11 pounds.
One of the subjects improved so much that she no longer met criteria for binge-eating disorder by the end of the study. There also appeared to be no significant adverse side-effects.
“This was a beautiful demonstration of how translational science can work in the best of cases,” said study co-lead author Camarin Rolle, PhD, a postdoctoral researcher with Halpern’s group.
The scientists have continued to follow the subjects for a further six months, and have begun enrolling new patients for a larger study.
They note that, in principle, the same treatment approach could be applied to other loss-of-control-related disorders, such as bulimia.
