Other studies have shown that VNS enhances BDNF release. Extinction training works to restore previous conditions and is one of the most effective ways to treat drug addiction,” Kroener said. In VNS, electrical pulses are sent to the brain through the vagus nerve via a device implanted in the neck. BDNF levels in their brains were elevated after just a single VNS extinction session, and they exhibited reduced drug-seeking behavior. Another experiment in the study indicated that VNS also seems to increase the staying power of the restorative changes to the brain.