Eligibility

• Inclusion criteria: Participants must be between the ages of 35 and 80 and meet criteria for either the frontotemporal dementia (FTD) [1], Alzheimer's disease (AD) [2], corticobasal degeneration (CBD) [3], progressive supranuclear palsy (PSP) [4], amyotrophic lateral sclerosis (ALS) [5] or healthy aging [6] group. Participants will need a reliable study partner who has frequent contact with the participant, is available to provide information about the participant, and who can accompany the participant to research visits as needed. Participants must be willing and able to have brain MRIs through the course of the study and have a Mini Mental State Exam (MMSE) score of 15 or greater at time of screening. Anyone not meeting these criteria will need to be approved by the Study Director [7].
• Exclusion criteria: A history of Korsakoff encephalopathy, alcohol abuse or dependence within 5 years of the onset of dementia, substance abuse, head trauma with a loss of consciousness greater than 30 minutes, brain tumor, multiple sclerosis, epilepsy, Parkinson's disease, communicating or non-communicating hydrocephalus, schizophrenia, bipolar affective disorder, intracerebral hemorrhage, B12 deficiency, hypothyroidism, HIV positive, renal failure, liver failure, respiratory failure requiring oxygen, dementia due to a condition other than those described above, cerebral infarct, large white matter lesions, significant systemic medical illness. Current medication likely to affect CNS functions: benzodiazepines more than three times weekly, no diazepam or triazolam but other short-acting benzodiazepines are fine; no amitriptyline or doxepin, SSRIs and other tricyclics are fine; no lithium; no neuroleptics in the phenothiazine or haloperidol families; no narcotics, codeine is fine but cannot be taken for 24 hours prior to cognitive testing; no anticonvulsants outside therapeutic ranges; and no antihistamines taken more than three times weekly, cannot be taken for 24 hours prior to cognitive testing.