 In single-word-recognition tasks, people who do not stutter showed cortical activation first in occipital areas, then in left inferior-frontal regions such as Broca's area, and finally, in motor and premotor cortices.The people who stutter also first had cortical activation in the occipital areas but the left inferior-frontal regions were activated only after the motor and premotor cortices were activated.During speech production, people who stutter show overactivity in the anterior insula, cerebellum and bilateral midbrain.