A pilot clinical trial involving two patients with loss-of-control binge eating disorder (BED) has shown the potential of a small device that detects brain activity associated with food cravings in a critical brain region and responds by electrically stimulating that region, according to the researchers.
The study, reported in a paper published today in Nature Medicine, monitored the two patients for six months while an implanted device similar to those used to treat drug-resistant epilepsy watched activity in the nucleus accumbens, a portion of the brain.
The processing of pleasure and reward occurs in the nucleus accumbens, which has also been linked to addiction. The gadget automatically stimulated the nucleus accumbens whenever it detected signals that had previously been shown to predict food cravings. This disrupted the signals that were associated with cravings. The patients reported significantly fewer binge episodes and weight loss after six months of therapy.
The study’s senior author, Casey Halpern, MD, an associate professor of neurosurgery and director 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.”
At least a couple million Americans are thought to be affected by BED, which is regarded as the most prevalent eating disorder in the country. It frequently involves binge-eating episodes without the bulimia-like purging, and is frequently linked to obesity. The person who is bingeing feels as though they are losing control over their food, so they eat past when they normally feel full.
Cravings for certain preferred meals occur before BED episodes. In a 2018 study using mouse and human studies, Halpern and colleagues discovered evidence that specific low-frequency electrical activity in the nucleus accumbens emerges only prior to these cravings—but not prior to regular, non-binge eating.
In order to stop this craving-related activity whenever it happened, the researchers activated the nucleus accumbens in mice. They discovered that the mice consumed substantially less of a delectable, high-calorie diet than they otherwise would have.
The scientists employed a gadget that is marketed and licenced for treating drug-resistant epilepsy to record signals from the mice’s brain and stimulate them. Wires connecting it to the nucleus accumbens in either hemisphere of the brain are surgically implanted beneath the scalp.
The new study served as a pilot experiment using humans to evaluate the same tool and tactic. The brain-stimulation devices were installed to each of the two BED patients who were extremely obese by Halpern’s team, and the devices’ signals were monitored for six months.
Fast food and candy were frequent items on the buffets served to the patients in the laboratory, but for the most part, they were at home going about their daily lives. When the patients were at home, they self-reported the times of their episodes, and the researchers were able to record the patients’ binge-eating episodes in the lab. The researchers found that, similar to their earlier research, the nucleus accumbens produced a characteristic low-frequency signal just before to the patients’ initial bites of their binge meals.
In the following phase of the trial, anytime the low-frequency signals associated with desire occurred, the brain stimulation devices automatically provided high-frequency electrical stimulation to the nucleus accumbens.
The patients saw significant decreases in their sensations of being out of control and the frequency of their bingeing episodes throughout this six-month period. They also each shed more than 11 pounds. One of the individuals made such significant progress that she ceased to meet the criteria for binge-eating disorder. There didn’t seem to be any noticeable negative side effects.
According to Camarin Rolle, PhD, a postdoctoral researcher with Halpern’s team and the study’s co-lead author, “This was a great display of how translational science can function in the best of instances.”