Sawing open someone’s skull for research purposes is a no-no, but brain scientists have found the next best thing. By projecting an electrical charge through the skull, they can now flick neurons on and off without ever breaking the skin.
The technique, known as transcranial magnetic stimulation, or TMS, uses a $30,000 contraption to fire a powerful magnetic pulse into the cranium, creating an electric charge that activates brain cells. That’s enough for some eye-catching parlor tricks: a zap above the temples makes muscles twitch involuntarily; one over the back of the head makes you see sparks. But the real magic begins when TMS pulses are fired in rapid succession. Depending on the frequency, repetitive TMS has long-term sensitizing or inhibitory effects, in principle allowing doctors to “rewire” the brain.
That has researchers reaching for their magnets. Doctors already use the technique to treat depression, stimulating areas of the brain that process moods; a large-scale clinical trial reports to the FDA next spring. And it doesn’t stop there: TMS can be used to speed up thought processes, boost creativity and even turn off the voices in schizophrenics’ heads. The military is interested in using the technique to turn off fatigue in soldiers. But forget about building your own orgasmatron: the brain’s pleasure centers are too deeply buried to be targeted by TMS.