CAMP LEJEUNE, N.C. — The explosion of practice mortars sent Army Spc. Kade Williams into panic attacks, and nightmares plagued his sleep. The ravages of post-traumatic stress had left the veteran of the war in Afghanistan vulnerable, and he was desperate for help.

But sitting silently on the floor with his eyes closed while listening to a soft-spoken instructor tell him to find a focal point by pressing on his lower stomach as guitar music hums in the background? That seemed a bit far-out.

Until he tried it.

"I will be the first one to admit that I was wrong," Williams said.

Warriors have long used such practices to improve concentration and relaxation — dating back more than 1,000 years to the techniques of the samurai. Here at coastal Camp Lejeune, 100 miles inland at the Army's Fort Bragg and at several bases in California, such meditation now comes with a name: Warrior Mind Training.

The course is catching on in military circles as a way not only to treat post-traumatic stress and traumatic brain injuries, but to improve focus and better prepare soldiers and Marines for the rigors of combat. It also can improve shooting range performance and raise training test scores, said Sarah Ernst, a senior Warrior Mind instructor.

At North Carolina's Camp Lejeune, the Marine Corps' main base on the East Coast, the courses are offered through the post naval hospital's "Back on Track" program, which helps wounded sailors and Marines with mental-health issues.

"This is a way to turn off your thoughts and get razor-sharp attention. We kind of work out the muscles, before our troops ever see action, so that they have the mental skill set to stay focused in the heat of battle — and to be able to leave the horrors of war behind when it's time to come home," Ernst said.

"Our motto is, 'Take the war to the enemy, but leave the battle on the battlefield.' "

Ernst started practicing relaxation techniques at Georgetown University 15 years ago. After the Sept. 11, 2001, terrorist attacks and the beginnings of the wars in Iraq and Afghanistan, Ernst read news stories about the rising number of soldiers with post-traumatic stress disorder or those committing suicide.

Using what she learned at Georgetown — such as the ability to relax and manages stress — Ernst said she developed a program specifically for the military. Although it sounds similar to common meditation and relaxation techniques, such as yoga, Ernst said Warrior Mind Training also encompasses ancient training techniques used by samurai, including an emphasis on living in the moment. Ernst said the samurai handled the carnage on the battlefield by only focusing on it during the fight.

"At the end of the day, a yellow ribbon bumper sticker is not going to cut it," she said. "If this is something that will help some of our soldiers, we should do it."

She and three other instructors started the Warrior Mind Training program at Camp Lejeune and Camp Pendleton, Calif. The program is free to service members and funded by the instructors.

It has grown to two courses a week at Camp Lejeune and Fort Bragg, and three a week at Camp Pendleton.

Petty Officer 1st Class Adam Credle learned about the classes from a flier. Credle, a Camp Lejeune-based instructor who trains his fellow Coast Guardsmen to operate speed boats, thought the classes might help him concentrate.

"Being able to focus on the here and now is pretty relevant when the boat is going 40 knots, because you are talking about a catastrophe if something goes wrong," Credle said.

Credle's first class took him into an exercise room at a gym on Camp Lejeune. Ernst, in jeans and a black blazer, sat at the front next to her iPod and speakers. She told the students to place two fingers just under their bellybutton, close their eyes and concentrate on that spot. Use the music, she said, as a focal point to clear the mind of all other thoughts.

Credle and three other students closed their eyes. For the next few minutes, the only sound was guitarist Joe Satriani's fingers dancing across his strings. Slowly, Credle's mind cleared.

Silence. Quiet. But only for a moment. Thoughts about the song and what he had to do the next day crept back into Credle's head. He quickly forced them out, then they flooded back in.

Ernst said it takes time to consistently reach a quiet place, but even being clear for a moment or two can have a significant shift on the day's mind-set. When she finally clears her mind, a huge toothy smile is plastered across her face.