Separating a real stutter from a fake one

What happens in the brain when someone stutters? New Zealand researchers trying to find out hooked up 11 volunteers to an MRI and made them fail on purpose, asking them to read a word but repeat the first letter multiple times. They found their brains lit up with the extra effort involved, clearly separating the task from an involuntary stutter. The researchers say their findings could help when treating people with speech difficulties who use voluntary coping mechanisms in their speech.