TAMPA (The New York Times News Service) -- The latest treatment for depression sounds like something out of science fiction: using an electromagnetic coil to beam pulsations through the skull to stimulate a part of the brain thought to be involved in depression.

Yet doctors using the therapy say the wildest thing about transcranial magnetic stimulation, or TMS, may be its potential to help some of the millions of Americans battling depression.

For patients who don't respond to drugs and counseling, TMS offers an alternative to electric shock therapy, still used to treat depression despite its reputation in popular culture as a barbaric treatment. Today, patients receive general anesthesia before having what doctors now call electroconvulsive therapy, or ECT, so they don't feel any pain when physicians use electric current to cause short seizures in the brain.

Many physicians consider ECT the gold standard treatment for depression that doesn't respond to other remedies. It's considered safe, but side effects can include short-term memory loss.

By contrast, the primary discomfort associated with TMS is a staccato tapping noise, resembling the racket of a woodpecker. Nor does it have ECT's image problem.

"TMS is far higher in acceptability to the patients and a lot less invasive," said Dr. Patrick Marsh, who recently began administering the treatment through the University of South Florida's Neurotherapies Clinic.

"We're targeting a specific area of the brain, as opposed to giving them medication, where you target the entire body," he said. "Or when they are having (electrically induced) seizures, which affect the whole brain."

Supporters of TMS, which has been researched as a possible treatment for depression since the mid 1990s, say it can help about half of patients who weren't helped by previous therapies. But questions linger about its effectiveness, both in the long- and short-term.

Another consideration is cost, which can reach $10,000 and isn't routinely covered by insurance because it is relatively new and its availability limited.

A bit of help, so far

Lindsey Underwood has tried years of counseling and more antidepression medications than he can recall. Still, nothing was helping when the 44-year-old recently found himself in a dark place, unable even to get out of bed and shower.

"I felt like I needed to try something different," said Underwood, who was motivated to get well for his wife and 2-year-old daughter. He thought TMS sounded a little odd, but "a lot less extreme than getting electric shocks."

For the past five weeks, Underwood has come to USF's clinic on Davis Islands almost daily for treatment. Each time, he goes to a windowless, second-floor room to sit in what looks like a dentist's chair, with a head restraint to deliver the 3,000 magnetic pulses per treatment.

Sessions last 37 minutes; Underwood gets 40 pulses in 4 seconds, then 26 seconds of recovery. He says the feeling amounts to a light finger tap on his forehead. Experts say the pulsations spark activity in the prefrontal cortex of the brain, the region associated with hopes, dreams and plans.

"The stimulation produces very small electrical currents, so small that you don't even feel it at all," said Dr. Francisco Fernandez, chair of the department of psychiatry at USF. "People hear the noise of the magnet, just like they hear the noise of the magnet when they're getting a MRI."

USF began offering the treatment in December and is the only provider in the Tampa Bay region, according to Neuronetics, the company that makes the only device federally approved to deliver TMS therapy.

At USF, the treatment costs about $350 per session, Fernandez said, and patients need about 10 to 20 procedures. USF has completed treating nearly 10 patients, only two of whom got insurance to pay for it.

Underwood, who is unemployed, paid out of pocket. The Washington state resident came to Tampa so he could stay with family while receiving the therapy, which is not available near his home. He said the cost is well worth it to him.

"I started having more energy, and thinking more positively a few weeks into it," said Underwood, who continued with anti-depressants and counseling during the therapy. He also started exercising, which can also help alleviate depression. "I do believe it's all things in concert."

Illness is common

Every year, about one in 10 Americans will struggle with a depressive illness .

Most people get better with talk therapy, drugs or a combination, but many do not respond to treatment, doctors say.

Treatment often is trial-and-error, since doctors can't predict what will work for each patient. But they do know that every time a treatment fails, odds increase that the patient won't respond to the next option.

So TMS, which was approved specifically for patients not helped by other treatments, targets those who already have the cards stacked against them.

Clinical trials on TMS have yielded mixed results, and the U.S.

Food and Drug Administration received some criticism when it approved the therapy for use in treatment-resistant depression more than a year ago.

At least some questions may be settled in May, when the results of a five-year study sponsored by the NIH will be published in the Archives of General Psychiatry.

Dr. George Northrup offered TMS from July to October at his private practice in south Tampa. But neither of the two patients he treated had substantial results. Then a private investor backing the service pulled out, so he stopped offering it.

Still, he's cautiously supportive of the therapy.

"The really difficult question becomes when you've been very ill for a long time and financially you're under a lot of pressure, because the cost-benefit analysis can be very complicated," said Northrup .

"It's easily tolerated," he said, pointing out that it doesn't have the side effects of medication. "If you can afford it, shoot, do it."

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