Role of Dopamine Receptors in Primary Focal Dystonias

Inclusion Criteria:

• Age >20
• Male or Female
• Any race or ethnicity
• Primary focal dystonia (arm or cranial)
• Ability to give informed consent

Exclusion criteria:

• Family history of dystonia
• Pregnancy (confirmed with negative urine pregnancy test in women of child bearing potential), breastfeeding
• Exposure to radiation therapy
• Any MRI contraindications such as foreign metallic implants, pacemaker, and aneurysm clip etc.
• History of cardiac disease, uncontrolled hypertension, abnormal EKG during screening phase
• History of exposure to any drugs affecting dopaminergic systems within the last 6 months (e.g. dopamine receptor blocking agents, cocaine, amphetamine, tetrabenazine, reserpine, L-dopa, dopamine agonists, as they might affect the dopamine receptor binding or endogenous dopamine).
• Active depression (Beck Depression Inventory_II >14)
• Cognitive impairment (Mini-Mental State Score <27)
• CNS active medications such as gabapentin or narcotics, muscle relaxants which might be given for pain in the 3 days prior to study
• History of stroke, seizure, cerebral palsy, generalized dystonia, parkinsonism, inability to hold head still during the scanning time.