Nitish V. Thakor, director of the Laboratory for Neuroengineering at Johns Hopkins University, embraces the fundamental scientific challenge of mapping electrical activity in the human brain. But what gets him out of bed in the morning, he says, are the clinical applications. He hopes the brain-machine interfaces he’s developing in collaboration with colleagues at the Hopkins School of Medicine will one day let paralyzed patients control robotic limbs with their brainwaves.