Screening and Evaluation of Patients With Signs and Symptoms of Alzheimer's Disease

Background: * Individuals who demonstrate symptoms of Alzheimer s disease, such as progressive memory loss, may be eligible to participate in National Institutes of Health research studies. However, other physical and psychological conditions may produce symptoms similar to those of Alzheimer s disease. To determine whether a patient meets the eligibility criteria to participate in a research protocol, researchers must perform a series of diagnostic tests and procedures. * These evaluations are designed to evaluate a participant s general medical condition (for example, blood tests and neurological exams) and to confirm a diagnosis or rule out an individual for consideration. They maximize the safety for participants in studies conducted at the National Institutes of Mental Health. Objective: \- To determine the eligibility of individuals for active Alzheimer s disease protocols. Eligibility: \- Individuals 45 years of age and older who have been having memory problems that have been getting worse with time and have been interfering with everyday life. Design: * Required tests and procedures for various research studies may include the following: * Medical history and physical examination, including a psychiatric evaluation. * Neuropsychological tests to test memory, mood, concentration, and thought processes. * Blood and urine tests. * Imaging studies (X-rays, magnetic resonance imaging (MRI), computerized tomography (CT), positron emission tomography (PET)). * Additional blood samples and MRI data for future use. * After all eligibility assessments are complete, participants may be offered participation in one or more research protocols