A disorder of the central nervous system that affects movement, often including tremors. Nerve cell damage in the brain causes dopamine levels to drop, leading to the symptoms of Parkinson’s. It often starts with a tremor in one hand. Other symptoms are slow movement (bradykinesia), stiffness and loss of balance. People are diagnosed with Parkinson’s at an average age of 60, anything younger than 50 is considered young-onset Parkinson’s, or YOPD.
