Diagnostic Imaging

Inclusion Criteria

- All:
 -- Males or females aged >/- 50 years 
 -- Participants must be able to understand the information provided on purpose and conduct of the clinical study, must be capable of giving fully informed consent in writing, and have read and signed the informed consent prior to study participation 
 - Healthy volunteers for brain imaging: 
 -- Mini-Mental State Examination (MMSE) score of >/= 28
 -- CDR score of zero (0) 
 - Patients for brain imaging: 
 -- Patient fulfills Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) and National Institute of Neurological and Communicative Disorders and Stroke, Alzheimer's Disease and Related Disorders Association (NINCDS-ADRDA) criteria for probable Alzheimer's Disease (AD), which are cognitive deficits such as memory decline and impairment in at least one other cognitive domain (e.g. aphasia, apraxia, agnosia or executive dysfunction) 
 -- Patient has mild to moderate dementia with a dementia score of >/= 20 on the Mini Mental State Examination (MMSE) / with a Clinical Dementia Rating score of 1 or 2 (CDR)

Exclusion Criteria

- All:
 -- No significant disease or drug use 
 - Patients for brain imaging:
 -- Evidence for any other neurological or psychiatric disease 
 - Healthy volunteers for brain imaging: 
 -- Family history of Alzheimer's Disease in a 1st or 2nd degree relative under 75 years of age