Brain stimulation techniques are reshaping how researchers think about treating addiction. Scientists now use magnetic pulses, sound waves, and electrical signals to target brain circuits damaged by substance use disorders. These approaches are gaining traction, and the early findings are hard to ignore.

The Addiction Policy Forum recently hosted a webinar bringing together three specialists to discuss what the research shows. Dr Redonna Chandler, Scientific Adviser at the Addiction Policy Forum, opened the session. She addressed attendees directly, stressing the urgent need for new approaches given the persistently high relapse rates following residential treatment.

Meet the Brain Stimulation Researchers

Dr Diana M. Martinez is Professor of Psychiatry at Columbia University Irving Medical Centre and Principal Investigator at the New York State Psychiatric Institute. She led the first half of the session with a detailed overview of transcranial magnetic stimulation (TMS). Her work centres on the brain mechanisms driving compulsive drug use and addiction.

Dr James J. Mahoney is Associate Professor and Clinical Neuropsychologist at the University of Virginia School of Medicine. He presented findings from his own clinical trials using focused ultrasound as an adjunctive neuromodulation treatment for opioid and polysubstance use disorder. He also directs the newly established Centre for Neuromodulation Research, Treatment and Technology at UVA, which opened in August 2025.

Both researchers made one point clearly: brain stimulation is not a cure. It works alongside existing treatments, whether medication or behavioural therapy, to reduce the cravings and emotional distress that so often derail recovery.

Why New Tools Are Needed

The numbers tell a sobering story. According to the National Survey on Drug Use and Health, approximately 48.4 million people in the United States received a substance use disorder diagnosis in 2024. Up to 75 per cent relapse within the first weeks after leaving a 28-day residential programme. For substances such as methamphetamine and cocaine, no approved medication treatments currently exist. Neuromodulation treatment, the researchers argued, has real potential to fill some of those gaps.

How Brain Stimulation Works: TMS Explained

TMS is the more established of the two brain stimulation approaches covered in the session. A clinician places a magnetic coil near the scalp. Electrical pulses generate a magnetic field that passes through the skull without resistance. This creates a secondary electrical field in the targeted brain tissue and alters the activity of neural networks linked to mood, impulse control, and craving.

The FDA approved TMS for major depression in 2008. Regulators later cleared it for obsessive-compulsive disorder and smoking cessation. For depression and OCD, roughly a third of patients reach full remission. Between 50 and 60 per cent show a meaningful clinical response. Effects typically last around six months, and clinicians can use booster sessions to extend those benefits further.

TMS for Smoking, Alcohol, and Other Substances

A pivotal multicenter randomised controlled trial published in 2021 tested TMS in tobacco use disorder. Between 17 and 27 per cent of completers stopped smoking. That figure is broadly comparable to nicotine replacement therapy or varenicline alone. One small Canadian study combined TMS with varenicline and reported quit rates of 60 to 80 per cent, suggesting real potential in combination approaches.

For alcohol use disorder, a 2023 meta-analysis in Neuropsychopharmacology reviewed all available studies. Multiple brain stimulation sessions reduced both alcohol craving and actual consumption. Single sessions made no difference. The field still needs a large multi-site randomised controlled trial to confirm these findings.

For cocaine use disorder, researchers have now conducted more than 20 studies. Many show reductions in craving and use. A definitive sham-controlled trial is still needed. Methamphetamine use disorder has fewer studies, but four randomised controlled trials show improved craving after multiple TMS sessions. Cannabis use disorder remains the most resistant. The largest trial to date found no effect on craving and only a modest reduction in days of use per week.

For opioid use disorder, four randomised controlled trials all show that TMS reduces craving compared to sham. Two of those studies also found significant reductions in depressive symptoms, which matters greatly given how often depression and addiction occur together.

Focused Ultrasound: A Neuromodulation Treatment That Goes Deeper

TMS reaches the outer regions of the brain. Focused ultrasound goes further. It targets deep subcortical structures at the heart of the brain’s reward system.

Dr Mahoney’s team focuses on the nucleus accumbens. This small structure plays a central role in compulsive drug-seeking behaviour. It connects with the prefrontal cortex, insula, dorsal striatum, and amygdala. Modulating it can regulate the wider reward circuitry, not just one isolated part.

The procedure uses a helmet fitted with thousands of ultrasound transducers. All of them direct energy from different angles and converge on one precise target. An MRI scanner guides the procedure throughout, monitoring temperature at the target site and detecting unexpected changes in real time.

Early Trial Results

Dr Mahoney’s team started with a four-person pilot study in 2021. They then progressed to a 16-person open-label trial using bilateral, simultaneous brain stimulation of both the left and right nucleus accumbens. Researchers recruited all participants from a residential 28-day treatment programme in Morgantown, West Virginia. All were already on medication for opioid use disorder. Fourteen had primary opioid use disorder. The group also included one person with primary methamphetamine use disorder and one with primary alcohol use disorder.

The results stood out. Cue-induced craving ratings fell sharply after the brain stimulation procedure. They stayed low throughout a 90-day follow-up period. The reductions were not limited to opioids. Craving scores for methamphetamine, cocaine, benzodiazepines, cannabis, alcohol, and nicotine all dropped substantially after a single session. Dr Mahoney credited this to targeting the reward circuit’s central hub, which is not substance-specific.

Urine toxicology results supported the picture. Most participants with primary opioid use disorder tested negative for all substances at every follow-up point across 90 days. Among those who did lapse, researchers noticed something different. Rather than spiralling towards crisis, participants reached out early, re-engaged with support, and returned to treatment quickly.

Participants also reported improvements across daily life. Anxiety fell. Focus improved. Frustration tolerance increased. Engagement with family, work, and education grew. Importantly, no reductions appeared in naturally rewarding activities such as eating or socialising, which matters because the nucleus accumbens also governs everyday pleasure.

Functional MRI scans backed this up. Researchers found reduced connectivity between the nucleus accumbens and both the dorsolateral prefrontal cortex and the posterior cingulate cortex. These changes persisted across the entire follow-up period.

Transparency About Risk

Dr Mahoney was open about a serious adverse event in the subsequent randomised controlled trial. One participant became unarousable following a second sonication during a crossover session. An MRI scan revealed microhaemorrhages both within and outside the nucleus accumbens. The participant recovered progressively over the following weeks but experienced intermittent confusion and memory difficulties.

The team halted the protocol on the same day. Clinical, engineering, neuroradiology, and device manufacturer teams all reviewed the case together. The device operated within its approved specifications. Inertial cavitation with an unusual acoustic signal feedback pattern was the most likely cause. The team introduced several risk mitigations: enhanced acoustic monitoring, real-time power modulation, and increased MRI imaging throughout the procedure. The FDA then approved continuation of the trial. One further participant has since received the treatment with no safety concerns.

What Brain Stimulation Research Looks Like Next

Dr Martinez called for trials combining brain stimulation with existing medications for alcohol use disorder. She also highlighted the lack of dedicated research for patients who live with both addiction and depression. Dr Mahoney pointed to device scalability as the most pressing near-term challenge. The current system requires continuous MRI and a stereotactic head frame. Newer devices under investigation at UVA need neither, which could make this neuromodulation treatment far more accessible.

Researchers are also exploring future applications, including cocaine use disorder, binge eating disorder, PTSD, gambling disorder, depression, anxiety, and treatments for adolescent populations.

The webinar painted a picture of genuine momentum. The science is not ready for widespread clinical use in addiction treatment just yet. But the right questions are now being asked, around dosing, patient selection, combination therapies, and long-term effects. That progress is worth watching closely.

Source: mailchi