INCREASED DOPAMINE ACTIVITY ASSOCIATED WITH STUTTERING

POSITRON emission tomography using 6-FDOPA as a marker of presynaptic dopaminergic activity was used to investigate the role of the dopamine system in stuttering. Three patients with moderate to severe developm ental stuttering were compared with six normal controls. Stuttering su bjects showed significantly higher 6-FDOPA uptake than normal controls in medial prefrontal cortex, deep orbital cortex, insular cortex, ext ended amygdala, auditory cortex and caudate tail. Elevated 6-FDOPA upt ake in ventral limbic cortical and subcortical regions is compatible w ith the hypothesis that stuttering is associated with an overactive pr esynaptic dopamine system in brain regions that modulate verbalization .