Imaging Biomarkers in Parkinson's Disease - Parkinson's disease
(PD) causes slow movement, stiffness, and tremor. It results
from the loss of a brain chemical called dopamine. PD gets worse
over time, but researchers do not fully understand why the brain
cells that produce dopamine stop working or die in people with
PD. This study will use different ways of imaging the brain and
brain chemicals to look at PD. It will compare brain imaging in
people who definitely have PD to people who might have PD and to
people without signs of PD. It will provide more information how
the brain in people with PD changes over time. - To understand
the changes that occur in the brains of people with Parkinson's
disease. - Individuals at least 18 years of age who have
definite or possible Parkinson's disease. - Healthy volunteers
at least 18 years of age. - Participants will have a screening
visit with a physical exam and medical history. Blood and urine
samples will be collected. - Participants will visit the
National Institut