Study Shows Magnetic Forces Help Heal Brain After Strokes

Dec. 14, 2011— -- Three days after her 21st birthday, Jenifer Schuerman had a stroke. When she emerged from her coma in the hospital, she was completely unaware of the left side of her body.

"Initially, there was no left side. It didn't dawn on me that there was another side," said Schuerman, now a 28-year-old student at Arizona State University.

If a family member spoke or a TV set blared from the left side of her bed, Schuerman could only look to the right. Initially, she said she was even unaware that her left side was completely paralyzed. After she could walk again, she constantly ran into walls on her left side.

"It was bizarre because my brain only acknowledged the right side," she said. "It's one of the most frustrating feelings I have ever experienced."

Doctors call the condition hemispatial neglect, and some studies estimate that 20 to 50 percent of stroke patients struggle with this lopsided condition. It happens most often when a stroke damages the right half of the brain.

A group of Italian researchers reported today that using magnets to stimulate the nerve cells of the brain can help remedy the condition. The treatment is called transcranial magnetic stimulation, and happens when doctors place a large electromagnetic coil against the scalp, creating electrical currents in one part of the brain.

"The treatment is based on the theory that hemispatial neglect results when a stroke disrupts the balance between the two hemispheres of the brain. A stroke on one side of the brain causes the other side to become overactive, and the circuits become overloaded," study author Dr. Giacomo Koch of the Santa Lucia Foundation in Rome said in a news release.

Koch and his colleagues studied whether using magnetic stimulation would help rebalance the activity on both sides of the brain. They tested 20 patients with hemispatial neglect, giving magnetic stimulation to 10 patients and a sham treatment to the other 10 patients. After two weeks, the patients who were magnetically stimulated performed 16 percent better on tests measuring their behavioral inattention, and their test scores improved by 23 percent after one month. The patients with the sham treatment showed no improvement.

The study was published today in the journal Neurology.

Even without treatment, patients can recover from hemispatial neglect after a few weeks. But Dr. Randolph Marshall, chief of the stroke division of Columbia University Medical Center in New York City, said the first few weeks of progress after a stroke, which are vital in a patient's overall recovery, can be derailed by the condition.

"The weakness they have from the stroke may be harder to rehabilitate because they can't pay attention to that weak limb," Marshall said. "Recovery will be delayed and potentially less robust if they're unable to participate fully and take advantage of their returning strength."

Other researchers have studied different methods of brain stimulation to speed recovery in stroke patients. British scientists reported in September that mild electrical currents sped up the brain's learning processes, a potentially promising development for impaired stroke survivors. Other researchers have experimented with magnetic stimulation in stroke patients, but doctors say the latest study's results are the most promising evidence so far that the treatment could actually work.

The study was a small one, however, and doctors emphasize that magnetic stimulation needs much more testing to determine whether it's a more effective treatment than the attention and concentration training that many stroke patients receive. And, ultimately, the real test of whether it works won't be found in a laboratory setting.

"The real test is how such an incremental decrease in visuospatial neglect improves functioning in daily activities, such as eating from both sides of the plate, finding people off to the neglected side when they speak and crossing the street safely," said Dr. Bruce Dobkin, director of the Neurologic Rehabilitation and Research Program at the University of California, Los Angeles.