Researchers have demonstrated for the first time that a noninvasive brain stimulation technique may dampen brain activity in response to drug cues in chronic alcohol or cocaine users.
A team from the Medical University of South Carolina has found that transcranial magnetic stimulation (TMS)—which targets magnetic stimulation to the ventromedial prefrontal cortex, circuitry critical for drug-taking behaviors——could help cut down on cravings for cocaine and alcohol for dependent users.
“Here, for the first time, we demonstrate that a new non-invasive brain stimulation technique may be the first tool available to fill this critical void in addiction treatment development,” senior author Colleen Hanlon, PhD, said in a statement.
While researchers have long known that addiction is largely a brain disease, they have not developed a neural circuit-based treatment for substance dependence or the brain functions involved in the disorder.
Elevated brain activity in response to drug cues—commonly called cue reactivity—occurs with many types of drugs, including nicotine, alcohol, marijuana, and cocaine. Cue reactivity also predicts relapse in addiction, so treatment approaches targeting the neural circuitry related to cue reactivity may directly affect cue-induced relapse in patients.
“Therefore, these results have a tremendous potential to impact both basic discovery neuroscience as well as targeted clinical treatment development for substance dependence,” Hanlon said.
The researchers based their conclusions on a study that included 25 people with cocaine-use disorder and a second study that focused on 24 people with alcohol-use disorder. Each participant received one TMS that was then compared to a fake session that mimicked the experience of receiving TMS without the actual brain stimulation.
The researchers found that when alcohol users viewed imaged of alcohol-related cues—like a liquor bottle—the single TMS session significantly reduced their drug cue reactivity. The same also proved true for cocaine users who viewed imaged of cocaine-related cues.
“Since cue reactivity has previously been associated with abstinence, these studies suggest a common mechanism for treatment effects across disorders, with fMRI serving as a promising neural readout of treatment effects,” Cameron Carter, MD, Editor of Biological Psychiatry: Cognitive Neuroscience and Neuroimaging, said in a statement.
Despite the promising results, it remains unclear if the changes in brain activity observed in the studies will ultimately translate to reduced drug and alcohol use, as the participants did not report any changes in their drug or alcohol cravings after TMS.
The researchers believe that repeated TMS sessions could be required to see changes in self-reported cravings. They now hope to conduct a clinical trial involving multiple TMS session for cocaine users.
According to Hanlon, elevated cue-reactivity is a core symptom in several other diseases, including post-traumatic stress disorder, generalized anxiety disorder, traumatic brain injury, smoking, and obesity.
The study was published in Elsevier.
