Dystonia Genotype-Phenotype Correlation

General Exclusion (both Dystonia and Control groups):

* Metal in any part of the body (including metal injury to the eye) OR carrying a medical device incompatible with MRI (e.g., metal implants such as surgical clips or pacemakers) OR positive screening per UTSW MRI screening form
* Claustrophobia
* Non-fluent English
* Weight incompatible with MRI safety
* History of head trauma with neurological sequelae, including multiple concussions and/or history of stroke
* Pregnancy
* Serious medical illness or history of serious medical illness, including cancer that was treated with radiation or chemotherapy, heart attack, or a known history of HIV-1 + status
* Subjects with Hepatitis C (by Hepatitis C+ titer)
* Subjects with insulin dependent diabetes mellitus (IDDM)
* Severe respiratory compromise
* In the opinion of the investigator, not able to safely participate in this study

Inclusion Criteria:

* Dystonia group

Previous diagnosis of dystonia which include but is not limited to:

* cervical dystonia (50 subjects)
* blepharospasm (25 subjects)
* limb dystonia (50 subjects)
* spasmodic dysphonia (25 subjects)
* segmental dystonia
* multi-focal dystonia
* Any childhood-onset dystonia (25 subjects) Age \> 11 years

  * Control group:

No prior dystonia diagnosis (175 subjects) Age \> 11 years

Exclusion Criteria:

* Dystonia group Prior history of or concurrent neurological or psychiatric diagnosis - depression and/or anxiety accepted Current use of non-dystonia neuroactive medications - SSRI/medication for depression and/or anxiety accepted Current use of cervical brace designed for dystonia treatment Prior structural brain injury

Control group:

History of or current neurological or psychiatric diagnosis - depression and/or anxiety accepted, but must not be in active phase Current use of any neuroactive medication, SSRI/medication for depression and/or anxiety accepted