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Doctors Say Electric Pulses Aided Brain-Damaged Man

ATLANTA, Oct. 15 — A team of neuroscientists reported Sunday that they had restored some movement and speech to a severely brain-damaged man by stimulating his brain with pulses of electric current.

The 38-year-old man, who had been barely conscious for six years, gradually regained the use of his left arm and began to utter coherent words for the first time since his injury in an assault, the doctors said.

Before surgery to implant two wire electrodes deep in his brain, he could respond to questions and commands occasionally, by moving his thumb or nodding, but was otherwise virtually mute and unable to move.

Experts said the case, presented at the annual meeting of the Society for Neuroscience in Atlanta, could revive interest in electrical stimulation for the estimated 100,000 to 200,000 Americans subsisting in states of partial consciousness.

But they added that it was far from clear how many would benefit, and that there were knotty ethical questions about operating on patients who could not give their consent.

Doctors have long used the implant surgery, known as deep brain stimulation, to treat the rigidity and tremors of Parkinson’s disease. They have also tried it in the past two decades on a handful of brain-damaged people, including Terri Schiavo, the Florida woman who died last year after her feeding tube was removed amid a national debate over her care.

But in those patients, the treatment was usually performed too soon after the injury to rule out spontaneous improvements, and in most cases, including Ms. Schiavo’s, it made no difference at all. The new case provides the first convincing evidence that the surgery can be helpful for some patients.

“I think this case suggests that this surgery probably will be one of the choices of treatment we can give to certain patients who have some chance of recovery, “ said Dr. James L. Bernat, a professor of neurology at Dartmouth Medical School, who was not involved in the case.

Dr. Bernat said he did not expect the treatment to help brain-damaged patients who had been totally unresponsive for more than a year. But for those who become occasionally or partly responsive after an injury, he said, “I think we should be aggressive and do whatever it takes” to induce improvement.

The research team, from NewYork-Presbyterian/Weill Cornell, the JFK Johnson Rehabilitation Institute in Edison, N.J., and the Cleveland Clinic Foundation, chose the patient as a test case for several reasons. He was partly conscious. His condition had been stable for years. And imaging tests showed that widely distributed language circuits running through his prefrontal cortex — the thinking, purposeful region of the brain — were intact.

Brain injuries from blows to the head, like the injury this man suffered, typically sever nerve connections widely throughout the brain but can leave some circuits still functional when stimulated.

The doctors threaded two wires through the man’s skull and into a subcortical area called the thalamus, which acts as a switching center for circuits that support arousal, attention and emotion, among other functions. The wires were connected to a pacemakerlike unit, implanted under the man’s collarbone.

Soon after the operation, and after the device was turned on to adjust the stimulation dose, the patient began to speak words, identifying pictures in a battery of tests, and became gradually more attentive. Some members of the research team then tracked the man’s abilities over four weeks while the current was turned on, and four weeks when it was off, without knowing when the device was activated.

They found a “consistent trend of improved verbal and behavioral responsiveness during the on condition,” said Dr. Nicholas D. Schiff, a neurologist at Cornell who was the lead author of the study, in an informal presentation of the work to other scientists on Sunday.

“He could be more independent chewing and swallowing,” and needed less help to eat, Dr. Schiff said.

Dr. Michele Tagliati, who runs the brain stimulation program for movement disorders at Mount Sinai School of Medicine in New York, said that no one knew how the stimulation affected brain circuits but that targeting the thalamus was a natural choice.

“If you want to restart the engine, so to speak, that is where you would go,” Dr. Tagliati said in a phone interview. “It’s a fascinating case.”

He said he had decided against recommending the surgery in the past for a severely brain-damaged patient after reviewing mixed results from previous studies in Japan and France. The new research, if replicated, could make the operation more attractive for some patients, he said.

Neuroscientists interviewed on Sunday said the operation also raised many ethical questions. Brain-damaged patients cannot give their consent to the surgery, and there is no way to predict the outcome.

The 38-year-old man, though improved, is still unable to say what he thinks about the surgery or to describe his own conscious state, said doctors not involved with the study who are familiar with the case.

The researchers withheld the patient’s name to protect his privacy. They said they had received consent for the operation from a family member legally authorized to give it.

“Given the legacy of psychosurgery, and that states of unconsciousness, like the vegetative state, can be so contentious, we have to be very concerned about ethical issues” like informed consent, said Dr. Joseph J. Fins, chief of medical ethics at Cornell and an author of the study. Dr. Fins added that any ethical framework to guide such treatment should not only affirm qualified patients’ right to care, but also “preserve their right to refuse it.”

A patient who regained decision-making ability with the surgery could very well decide not to continue treatment, he said.

But for all the hopes and questions it raises, experts said, this case represents a culmination of years of growing knowledge about brain imaging, rehabilitation techniques, stimulation surgery, and data from animal studies revealing which circuits are important for arousal.

“Even though this is a first step, it is of utmost importance, because is shows that this therapeutic approach is worth studying,” said Dr. Steven Laureys, a neurologist at the University of Liège in Belgium. “I can only hope that further cases will confirm this result, because if that would fail, we would see this whole idea go back into the fridge for a long time.”

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