Bleary-eyed, the pilot stares at the instruments while sipping stale coffee. The cup is nearly empty, as is the radar screen. So, he realizes, are the airplane's fuel tanks, not to mention his own energy reserves. Another cup certainly won't help much. His co-pilot dozes beside him, having already flown several legs of their long mission to deliver sorely needed humanitarian aid to the other side of the world. The pilot considers, then rejects popping a pep pill. Uppers make him jumpy, a bad feeling to have during the tricky nighttime aerial-refueling maneuver he will soon have to execute. Suddenly the radar shows a blip orbiting up ahead. Scanning the cloudy sky for the tanker's navigation lights, the pilot knows he has to get focused fast. He flips a switch. A "rat-a-tat-tat" sound, like that of a staple gun, echoes through his helmet, and fatigue abruptly flees his mind. Clear-headed for the first time in what seems days, the pilot almost immediately spies lights flashing in the murky distance. He nudges the co-pilot, who absently toggles his own switch as he stifles a yawn. Muffled snapping noises follow. Fully awake, the aviators steer for the flying gas station circling overhead.
In the scenario above, sharp sounds emerge when electromagnets inside the helmets generate magnetic fields to excite particular parts of the pilots' brains--areas that govern tiredness and wakefulness. Neuroscientists developing this novel noninvasive technique call it transcranial magnetic stimulation (TMS). TMS employs head-mounted wire coils that send strong but very short magnetic pulses directly into specific brain regions, thus safely and painlessly inducing tiny electric currents in a person's neural circuitry.
This article was originally published with the title Stimulating the Brain.