Studies utilizing positron emission tomography (PET) have found during tasks that invoke disfluent speech, people who stutter show hypoactivity in cortical areas associated with language processing, such as Broca's area, but hyperactivity in areas associated with motor function.[1] One such study that evaluated the stutter period found that there was over activation in the cerebrum and cerebellum, and relative deactivation of the left hemisphere auditory areas and frontal temporal regions.[2]