Hope for Alzheimer's? Deep Brain Stimulation

Electrical Currents in the Brain May Help Patients Locate Lost Memories

By JOHN McKENZIE
ABC News Correspondent

Jan. 30, 2008—

Researchers report what they say is a world first: By implanting a device in a man's brain, they have improved his memory. The discovery, published today in the Journal of Neurology, raises the possibility of using this technique to treat Alzheimer's patients.

Surgeons made this accidental discovery while a 50-year-old-male patient was undergoing "deep brain stimulation," as part of an experimental treatment for obesity.

With the patient under local anesthesia, but fully awake, surgeons traveled into the deepest recesses of the brain, moving gingerly at a quarter of an inch an hour, listening to electrical "pulses," as millions of brain cells communicated with each other.

"The language of the brain is electricity," said Dr. Ali Rezai, of the Cleveland Clinic. "By applying electrical currents, we can actually shut down different parts of the brain, or activate different parts of the brain."

Surgeons treating the obese patient hoped that adding electrical signals to his brain would regulate his appetite.

But amazingly, in the midst of the operation, something completely unexpected happened. The patient suddenly reported a flood of intricately detailed memories from an incident decades ago.

Dr. Andres Lozano, of Toronto Western Hospital, said, "He reported he was in a park, that he was with his friends. He recognized the people and what they were saying. When we increased the stimulation, the details filled in."

That was just the beginning. Over the next year, researchers discovered that the man, who initially had normal memory before the operation, now scored significantly higher on memory and learning tests when the current was turned on.

"This is the first time anyone has had electrodes implanted in the brain which have been shown to improve memory," Lozano. "We are stimulating memory circuits in the brain."

With this discovery, researchers can study the possibilities of using the technique with Alzheimer's patients. Preliminary results look promising, but it will take several more years of testing to know for certain whether a mild electrical current can spark memories, locked away by this devastating disease.

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