Put a powerful magnet against the side of your head and it can interfere with the neurons working underneath. The technique is being used to treat severe depression, but it can also produce some nifty party tricks. In this video, a magnet held to left side of New Scientist editor Roger Highfield's skull interrupts his ability to speak a nursery rhyme. But when Highfield sings the same rhyme, there's no effect. That's because the neurons that control speech and the neurons that control singing are in separate parts of the brain. The magnet disabled Highfield's speech centers, but left his ability to sing untouched.