WEDNESDAY, Dec. 14 (HealthDay News) -- Stroke patients suffering
from a condition that prevents them from sensing or reacting to
anything happening to their left -- whether it's noticing food on a
plate or recognizing a person sitting to that side -- may recover
faster with magnetic stimulation to the nerve cells in their brain,
Italian researchers report.
This inability to process and perceive stimuli on the left side
of the body, called hemispatial neglect, is common after a stroke
occurring on the right side of the brain, affecting up to 50
percent of patients. The researchers say that the current treatment
of attention and concentration training through computer and
pencil-and-paper tasks is not useful.
"This problem also affects motor function," explained lead researcher Dr. Giacomo Koch, from the Santa Lucia Foundation in Rome. "It is important to treat not only to speed up cognitive recovery, but also motor recovery."
Most patients recover spontaneously after about a year, he
noted. The study was published in the Dec. 13 online edition of
Neurology.
In the study, Koch's team randomly assigned 20 patients with
hemispatial neglect either to a sham treatment or to 10 sessions of
magnetic stimulation over two weeks. All 20 patients also received
conventional treatment. Patients were given tests to measure their
ability to process information on the neglected side of the
body.
In the technique, called transcranial magnetic stimulation, a
large electromagnetic coil is placed against the patient's scalp
creating electrical currents that stimulate nerve cells.
The researchers found that patients who received the magnetic
stimulation had a 16 percent improvement on the tests by the end of
two weeks and a 23 percent improvement two weeks later. The test
scores of patients who received the sham treatment did not
improve.
The condition produces overstimulation in the left side of the
brain, Koch said. Overactive brain circuits returned to normal in
patients who received stimulation, but did not in those who got the
sham treatment, the researchers found.
Dr. Randolph Marshall, chief of the stroke division at Columbia
University Medical Center in New York City and co-author of an
accompanying journal editorial, said that "scientific advances in
our understanding of brain function are allowing us to develop
effective ways of improving outcomes in patients who lose function
as a consequence of stroke."
"As our population ages, the total number of strokes will rise over the next 10 to 20 years," he said. "Work like this is crucial to help improve outcomes of stroke victims."
The brain works to a large degree by balancing excitation
between the two hemispheres, Marshall said.
"A good example is directing one's attention to one side or the other. With stroke in one side of the brain, the balance between the two cerebral hemispheres is thrown off, and the stroke victim cannot attend to one side of space," he explained.
"Magnetic stimulation, in combination with physical therapy, reduces the over-excitability in the side of the brain opposite to where the stroke occurred," Marshall added.
"What is important in this article is that the authors were able to demonstrate both the improvement in directed attention, and the underlying electrophysiology that allowed it to happen," he said.
Another expert, Dr. Larry Goldstein, director of the Duke Stroke
Center, expressed some caution about the findings.
"This is an interesting preliminary study," he said. "Whether this results in a clinically meaningful improvement in ways that affect daily activities, and whether it is generalizable in other settings. requires further study," Goldstein said.
More information
For more about stroke, visit the
U.S. National Stroke Association.