Onstage at the Renée and Henry Segerstrom Concert Hall in Costa Mesa, an older couple assumes a ballroom dance position. A tango begins, and the man, wearing a porkpie hat and suit, leads. The woman, wearing a floral dress, follows gracefully.

Judging by the ease and fluidity of their movements, one would never know that Nancy Dufault, 72, has Parkinson's disease. When she is dancing, moving in time with her husband, Bob, she experiences a brief respite from symptoms.

"She asked me to write a tango," says Mike Garson, a classically trained pianist who played with David Bowie for nearly 40 years. Garson composed the piece to which the couple is dancing. "When she dances, her tremors are less."

Garson, in collaboration with Nancy Dufault's doctor, Orange County-based neurosurgeon Christopher Duma, created the evening's music with the goal of using it as a form of therapy. "The Symphonic Suite for Healing" concert includes 11 movements in addition to the tango. The compositions were developed to explore the healing power of music.

The idea for the show, says Garson, was his own. "I've always felt that music heals people. Anyone who plays music knows it. I'm just calling attention to it."

"The Symphonic Suite for Healing" was born when Garson and Duma met at a function several years ago. Duma, a musician himself, was fascinated with the idea that music could have healing properties: stroke victims might move more easily, Alzheimer's patients might recall old memories.

The two decided to collaborate, and Duma's Foundation for Neurosciences, Stroke and Recovery commissioned Garson to put together 30 pieces of music. Duma enlisted his patients to listen to them and report back on how they felt.

"I can listen to [certain music] and feel healed," says Duma, and it turned out that his patients felt the same way.

Duma had nearly 100 people listen to three pieces of music each. They then reported back on how they felt — whether angry or calm, more relaxed or more agitated. The results, he says, were remarkable. Music triggered the memories of Alzheimer's patients. And Parkinson's sufferers could better accomplish a physical test to put pegs in holes while listening to the music.

"There's tension in music," says Duma, "and then it resolves. When you have these tension releases, they hit us in our brain, and they make us feel good. We can play with that in the future. This is just the tip of the iceberg."

That the tests were successful, says Garson, comes as no surprise.

"The testing satisfies the scientific community and doctors," he says, "but for me, it's like, 'Well, now you're waking up to something we've known for 500 or a thousand years.'"

Using music as a means of therapy isn't new. According to the American Music Therapy Assn., it has been used in healing and medicine since the late 1700s, and the profession began in earnest in the early 1900s.

Christine Deelo, a Los Angeles-based music therapist, says music can have a positive, calming effect on patients. "I've used music with patients in the hospital coming out of surgery or going into surgery, and it not only blocks out other stimuli in the hospital, you can use the music to help them relax."

But Garson wasn't as interested in the science while composing the "Symphonic Suite." In fact, he says, once he had the idea, the pieces began to flow through him without much of a thought as to what they could accomplish.

"Once you set the intention, you don't have to keep saying to yourself, 'I'm healing, I'm healing,'" he says. "That would be nuts."

Instead, Garson wrote what he was feeling at the time, without any particular illness in mind — although, he adds, part of what inspired him was the effect music has had on his autistic grandson. "He was very anxious for about four or five years, and when I put him on my lap and started playing the piano, he started to relax in a way that I had never seen. He sort of sank into the music."

Science has a long way to go in understanding how music works on the brain. A handful of studies have used MRIs to observe the brain's reaction to music, but it still isn't clear what exactly the mechanisms are for its tangible physical effects on patients with degenerative diseases.

Duma believes that Parkinson's may offer a window into the answer — the illness affects the basal ganglia, the area of the brain responsible in part for controlling fluid movement. When Parkinson's patients become more relaxed, their symptoms often ease.

"There is a huge interaction between emotion and problems with movement," Duma says. "The same goes for dancing and Parkinson's."

Both Garson and Duma hope that more testing can be done.

"What is it about that music that helps?" Duma asks. "Is it the resolution of chords? Is it a certain tempo? We need more help and time with finding out that type of thing."

But, he says, he foresees a future in which music could be used like any other medicine.

"Why can't I, in the future, prescribe for someone who has high blood pressure listening to music three times a day instead of taking their high blood pressure [medication] three times a day?" he says. "We are really missing out on things."

health@latimes.com