Advancing Research and Treatment for Frontotemporal Lobar Degeneration (ARTFL)

1. Inclusion Criteria:Must meet one of the following research diagnostic criteria for a Frontotemporal lobar degeneration (FTLD) syndrome: behavioral variant frontotemporal dementia (bvFTD), primary progressive aphasia (PPA), semantic variant primary progressive aphasia (svPPA), nonfluent variant primary progressive aphasia (nfvPPA), frontotemporal dementia with amyotrophic lateral sclerosis (FTD/ALS), amyotrophic lateral sclerosis alone, corticobasal syndrome (CBS), progressive supranuclear palsy (PSP) or oligosymptomatic PSP (oPSP), or have a strong family history of FTLD syndromes. 2. Between 18 and 85 (inclusive) years of age. 3. Able to walk (with assistance) at the time of enrollment. 4. Have a reliable study partner who can provide an independent evaluation of functioning. 5. Speak English or Spanish 6. Have Mini Mental State Exam (MMSE) scores between 15 - 30 (inclusive). Exclusion Criteria: 1. Known presence of a structural brain lesion (e.g. tumor,cortical infarct) that could reasonably explain symptoms in a symptomatic participant without a known f-FTLD causing mutation. 2. Known presence of an Alzheimer's disease causing mutation in PSEN1, PSEN2 or APP; or neuropathological evidence for Alzheimer's disease as a cause of syndrome (from brain biopsy). 3. A previous history of Korsakoff encephalopathy, severe alcohol dependence (within 5 years of onset of dementia), frequent alcohol or other substance intoxication, or other neurological disorder (such as multiple sclerosis) 4. Evidence through history or laboratory testing of B12 deficiency (B12 \< 95% of local laboratory's normal value), hypothyroidism (TSH \>150% of normal), HIV positive,renal failure (creatinine \> 2), liver failure (ALT or AST \> two times normal), respiratory failure (requiring oxygen), extra-axial brain tumor (with visible compression of the brain parenchyma), large cerebral infarct that could account for clinical syndrome, large confluent white matter lesions (grades 3 or 4, \[107\] significant systemic medical illnesses such as deteriorating cardiovascular disease; 5. Current medication likely to affect CNS functions in the opinion of the site PI: long acting benzodiazepines such as diazepam (short-acting benzodiazepines are OK), non-SSRI antidepressants (SSRIs or trazodone are OK), no lithium, typical neuroleptics as listed in the Manual of Procedures, narcotics (codeine is OK, but hold 24 hours before neuropsychological testing), anticonvulsants (outside of therapeutic ranges), antihistamines (if taking greater than three times per week; hold 24 hours before neuropsychological testing). 6. In the site investigator's opinion, the participant cannot complete sufficient key study procedures, or equivalent assessment of impairment level. 7. For groups where MRI scans are planned procedures, any contraindication for MRI scanning, such as pacemaker or other implanted metals.