Mapping of brain tau deposition in tauopathy by PET with [11C]PBB3

INTERVENTION: PET/MRI/psychological batteries/neurological examinations PET/MRI/psychological batteries/neurological examinations PET/MRI/psychological batteries/neurological examinations PET/MRI/psychological batteries/neurological examinations PET/MRI/psychological batteries/neurological examinations PET/MRI/psychological batteries/neurological examinations CONDITION: Healthy volunteers 20 years of age or older at the time of obtaining consent Patients with mild cognitive impairment (MCI) 20 years of age or older at the time of obtaining consent Patients with Alzheimer's disease (AD) 20 years of age or older at the time of obtaining consent Patients with corticobasal degeneration (CBD) 20 years of age or older at the time of obtaining consent Patients with progressive supranuclear palsy (PSP) 20 years of age or older at the time of obtaining consent Patients with frontotemporal dementia (FTD) 20 years of age or older at the time of obtaining consent Patients with familial Parkinson's disease with the LRRK2 genetic mutation (PARK8) PRIMARY OUTCOME: Distribution volume and binding potential measured by positron emission tomography with [11C]PBB3 ; ‐ Comparison between patients and age‐ and gender‐matched healthy controls INCLUSION CRITERIA: healthy volunteer 1. 20 years of age or older at the time of obtaining consent. For the judgment of whether or not subject cognitive function can be deemed normal. 2. In order to reduce gender bias, subjects will be selected to match the male‐to‐female ratios of the patient groups to the maximum extent possible. 3. Healthy subjects who have the ability to consent to participate in this study, to read and understand the informed consent form. Patients with MCI, AD, CBD, PSP, FTD and PARK8 1. Patients 20 years of age or older at the time of obtaining consent. 2. Patients with MCI and patients with AD: Patients meeting the inclusion criteria in the J‐ADNI core study except for age. However, the range of CDR (Clinical dementia rating) in patients with AD will be 0.5‐2, and the range of MMSE (Mini Mental State Examination) will be 26 points or less, and the acceptable range of drugs that can be used will be partially changed. Patients with CBD