Fixing Your Brain
When pills fail, electrical implants can mend brains damaged by Parkinson's, stroke, and depression
ATLANTA--Mickey Lawson's brain is talking. The 63-year-old picture framer from Lawrenceville, Ga., is strapped to a surgical table in operating room 15 at Emory University Hospital. He is also trapped in the rigid embrace of Parkinson's disease, which in the past decade has robbed him of speech and muscle control. Yet his brain is quite lively, and in the OR this afternoon in late January, everyone can hear it.
A loud popping begins echoing from a speaker. "You can hear it's pretty active," says neurosurgeon Robert Gross. He is gingerly guiding an electrode--a wire only a few millionths of an inch thick--into Lawson's brain through a nickel-size hole in his skull. It's picking up the sounds of neurons firing electrical impulses, the very stuff of thoughts and commands. Gross has pushed into part of an essential motor circuit that's damaged in Parkinson's. By putting a battery-powered device like a pacemaker in Lawson's chest and hooking it up to an implanted electrode, via a wire under the skin of his neck and scalp, Gross intends to stimulate that circuit and get Lawson moving smoothly again.
His brain feels no pain from the implant. But Lawson does, awake while under a local anesthetic so doctors can ask him about sensations evoked by the electrode. His head is squeezed in a metal brace to keep it from moving, his body racked by spasms from his disease. "Mr. Lawson?"asks an anesthetist, "Are you OK?" He squeezes her hand hard in reply.
This is deep brain stimulation, and Lawson is among the latest of about 30,000 people in the United States to get it. Drugs have failed him, so this is the next step. Lawson hopes to end up like Lucian Kent, 69, who had the procedure last November. "Once they turned the electrode on, it was like a magic wand," says the retired police
officer who lives in Philadelphia, Tenn. "I used to be in a wheelchair. Now I'm walking, and my balance is better. I do water aerobics."
Welcome to the new science of brain repair. Doctors are now using tiny electrical devices to help mend broken brains--and not only those injured by Parkinson's. Neurologists at several hospitals have just started a major trial of a promising implant that can fix brain damage caused by strokes. Last year, the Food and Drug Administration also approved a nerve stimulator to treat serious depression. And at a neuroscience meeting in Washington, D.C., in November, scientists showcased a brand-new implant that allows a quadriplegic to control a remote robotic arm with, literally, his mind. Says Harold Sackheim, a brain stimulation expert at the New York State Psychiatric Institute: "There's a ton of stuff going on."
It's all being pushed by tremendous advances in brain mapping, allowing doctors to target tiny areas, and new implants with computer chips to control them that can fit in these small spaces. "But the big thing is that our understanding of targets has changed," Sackheim says. "The brain is an electrical organ. And there is no more efficient way of getting it to act than by using a tiny electrical current. You can't get drugs, for example, to target just one region. That's why you see all sorts of bad side effects. We're seeing the start of a whole new class of medicine."
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