Resetting the Brain

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Using a slightly different approach, Dr. Alvaro Pascual-Leone at Harvard Medical School is beginning to see improvements in his stroke patients' speech. Instead of boosting activity in the compensating areas of the brain, Pascual-Leone is trying to disrupt the neural pathways that block recovery. "What the brain tries to do as a first-line response is to shut down activity in damaged areas," he explains. That gives the neurons that are only slightly damaged a chance to recover before coming back online. But in some stroke patients, the inhibitory network never lets up. By weakening those neurons with magnetic stimulation, Pascual-Leone thinks he can give the recovery process a gentle boost.

These scientists are the first to admit that they are treating a dizzyingly complex organ--the human brain--with not much more than educated guesswork. But when you hear the gratitude in Martha's voice as she talks about what it's like to get her life back after so many years of deep depression, it seems a risk worth taking. --With reporting by Alice Park/ New York