Below are definitions for key terms used in this book.
alpha-synuclein: A protein that is misfolded, or altered, in people who have Parkinson’s disease. The misfolded protein forms clumps in nerve cells and likely contributes to nerve cell death.
dopamine: A chemical that is released from nerve cells in areas of the brain that are affected by Parkinson’s.
levodopa: A drug that is converted into dopamine and is a highly effective medication for Parkinson’s disease.
Lewy bodies: The clumps of misfolded alpha-synuclein and other proteins that are found in the brains of individuals with Parkinson’s disease.
LRRK2: A specific gene that codes, or gives building instructions, for a protein in the brain and other parts of the body. Mutations in this gene are the most common genetic cause of Parkinson’s disease.
mitochondria: The energy-producing parts of cells, which are damaged in Parkinson’s and by some pesticides.
MPTP: An accidental chemical by-product of a street formulation of synthetic heroin. MPTP kills dopamine-producing nerve cells and has caused parkinsonism in some users of heroin.
neurotransmitter: A chemical that is released from nerve cell endings and enables communication between cells.
parkinsonism: A general term for any syndrome that causes tremors, slowed movements, stiffness, and imbalance. This condition has many causes, including Parkinson’s disease, certain medications, and other diseases.
pesticide: Any substance used to prevent, destroy, repel, or mitigate any pest, including herbicides (for weeds), insecticides (for insects), and fungicides (for fungi) among other chemicals.
substantia nigra: A Latin phrase that literally means “black substance.” It refers to a small region of the brain that contains pigmented dopamine-producing nerve cells, which are damaged in people who have Parkinson’s disease.