Instrumented Data Exchange for Ataxia Study

Inclusion Criteria: * SCA 1, 2, 3, 6, and FA with mutations in the pathogenic range confirmed from genetic testing * SCA: aged 18-75 years * FA: aged 12-30, diagnosed between ages 5-25 * community dwelling * physically/cognitively capable of consenting/assenting and complying with the protocol based on investigator's judgement * able to walk independently 10 yards without an assistive device * able to sit or stand unassisted for 30 seconds * no other neurological or musculoskeletal disorder that could affect mobility * no other history of head injury, vestibular function, stroke, or other disorders that could affect mobility * willing and able to participate in a 2-year study * consent to be video recorded while performing study assessments Exclusion Criteria: * dementia that limits subjects' ability to follow directions * pain that limits mobility * SCA: enrolled in a clinical drug trial