Tony didn’t know what to expect when he walked into the Brain Treatment Center in San Diego, California, last spring. The former Navy SEAL only knew that he needed help. His service in Iraq and Afghanistan was taking a heavy toll on his mental and physical wellbeing. He had trouble concentrating, remembering, and was given to explosive bursts of anger. “If somebody cut me off driving, I was ready to kill ’em at the drop of a hat,” he said. And after he got into a fistfight on the side of a California road, his son looking on from the car, he decided he was willing to try anything — even an experimental therapy that created an electromagnetic field around his brain.

What Tony and several other former U.S. Special Operations Forces personnel received at the Newport Brain Research Laboratory, located at the Center, was a new treatment for brain disorders, one that might just revolutionize brain-based medicine. Though the FDA clinical trials to judge its efficacy and risks are ongoing, the technique could help humanity deal with a constellation of its most common mental disorders — depression, anxiety, aggressiveness, attention deficit, and others—and do so without drugs. And if its underpinning theory proves correct, it could be among the biggest breakthroughs in the treatment of mental health since the invention of the EEG a century ago.

At the lab, Tony (whose name has been changed to protect his identity) met Dr. Erik Won, president and CEO of the Newport Brain Research Laboratory, the company that’s innovating Magnetic EEG/ECG-guided Resonant Therapy, or MeRT. Won’s team strapped cardiac sensors on Tony and placed an electroencephalography cap on his skull to measure his brain’s baseline electrical activity. Then came the actual therapy. Placing a flashlight-sized device by Tony’s skull, they induced an electromagnetic field that senta small burst of current to his brain. Over the course of 20 minutes, they moved the device around his cranium, delivering jolts that, at their most aggressive, felt like a firm finger tapping.

For Tony, MeRT’s effects were obvious and immediate. He walked out of the first session to a world made new. “Everything looked different,” he told me. “My bike looked super shiny.”

He began to receive MeRT five times a week— each session lasting about an hour, with waiting room time — and quickly noticed a change in his energy. “I was super boosted,” he said. His mood changed as well.

Today, he admits that he still has moments of frustration but says that anger is no longer his “go-to emotion.” He’s developed the ability to cope. He still wants help with his memory, but his life is very different. He’s taken up abstract painting and welding, two hobbies he had no interest in at all before the therapy. He’s put in a new kitchen. Most importantly, his sleep is very different: better.

Tony’s experience was similar to those of five other special-operations veterans who spoke with Defense One. All took part in a double-blind randomized clinical trial that sought to determine how well MeRT treats Persistent Post-Concussion Symptoms and Post-Traumatic Stress Disorder, or PTSD. Five out of the six were former Navy SEALS.

In many ways, SEALS represent the perfect test group for experimental brain treatment. They enter the service in superb health and then embark on a course of training that heightens mental and physical strength and alertness. Then comes their actual jobs, which involve a lot of “breaching”: getting into a place that the enemy is trying to keep you out of. It could be a compound in Abbottabad, Pakistan—or every single door in that compound. Breaching is so central to SEAL work that it’s earned them the nickname “door kickers.” But it often involves not so much kicking as explosives at closer-than-comfortable range. “I got blown up a lot in training,” says Tony, and a lot afterwards as well. Put those two factors together and you have a population with a high functioning baseline but with a lot of incidents of persistent post-concussive syndrome, often on top of heavy combat-related PTSD and other forms of trauma.

One by one, these former SEALs found their way to Won’s lab. One — let’s call him Bill — sought to cure his debilitating headaches. Another, Ted, a SEAL trainer, had no severe symptoms but wanted to see whether the therapy could improve his natural physical state and performance. A fourth, Jim, also a former SEAL, suffered from severe inability to concentrate, memory problems, and low affect, which was destroying his work performance. “I was forcing myself to act normal,” Jim said. “I didn’t feel like I was good at anything.”

Yet another, a former member of the Air Force Security Forces named Cathy, had encountered blasts and a “constant sound of gunfire” during her deployments to Iraq and Afghanistan. She suffered from memory problems, depression, anger, bouts of confusion, and migraines so severe she had to build a darkroom in her house.

Like Cathy, the rest had difficulty sleeping. Even Ted, who had no severe PTSD-related problems, reported that he “slept like crap,” before the treatment began.

All said that they saw big improvements after a course of therapy that ran five days a week for about four weeks. Bill reported that his headaches were gone, as did Cathy, who said her depression and mood disorders had lessened considerably. Jim’s memory and concentration improved so dramatically that he had begun pursuing a second master’s degree and won a spot on his college’s football team. Ted said he was feeling “20 years younger” physically and found himself better able to keep pace with the younger SEALS he was training. All of it, they say, was a result of small, precisely delivered, pops of electricity to the brain. Jim said the lab had also successfully treated back and limb pain by targeting the peripheral nervous system with the same technique.