Imaging Genetics of Laryngeal Dystonia

Inclusion criteria: 1. Males and females of diverse racial and ethnic background, with age across the lifespan; 2. Laryngeal Dystonia patients * phenotype: adductor or abductor * genotype: familial or sporadic 3. Voice Tremor patients * essential or * dystonic 4. Muscle tension dysphonia patients 5. Unaffected relatives of laryngeal dystonia patients with * familial laryngeal dystonia * early-onset laryngeal dystonia (onset at ≤ 35 y.o.) * typical onset laryngeal dystonia (onset at ≥ 40 y.o.) 6. Native English speakers. 7. Right-handedness. 8. Normal cognitive status. Exclusion criteria: 1. Subjects who are incapable of giving informed consent. 2. Pregnant or breastfeeding women until a time when they are no longer pregnant or breastfeeding. 3. Subjects with past or present medical history of (a) major neurological problems, such as stroke, movement disorders (other than LD and VT in the patient groups), brain tumors, traumatic brain injury with loss of consciousness, ataxias, myopathies, myasthenia gravis, demyelinating diseases, alcoholism, drug dependence; (b) psychiatric problems, such as schizophrenia, bipolar depression, obsessive-compulsive disorder; (c) laryn¬geal problems, such as vocal fold paralysis, paresis, vocal fold nodules and polyps, carcinoma, chronic laryngitis. 4. Patients who are not symptomatic due to treatment with botulinum toxin injections into the laryngeal muscles. 5. Subjects who receive medication(s) affecting the central nervous system. 6. Subjects with a history of major brain and/or laryngeal surgery. 7. Subjects who have tattoos, ferromagnetic objects in their bodies that cannot be removed for imaging study participation.