Parkinson’s occurs when certain nerve cells (neurons) in a part of the brain called the substantia nigra die or become impaired. Normally, these cells produce a vital chemical known as dopamine. Dopamine allows smooth, coordinated function of the body’s muscles and movement. When approximately 70% of the dopamine-producing cells are damaged, the symptoms of Parkinson disease appear. Parkinson’s is progressive, which means it gets worse over time. But usually this happens slowly, over a period of many years. And there are good treatments that can help you live a full life.
The disease is named after the English doctor James Parkinson, who published the first detailed description in An Essay on the Shaking Palsy in 1817. Several major organizations promote research and improvement of quality of life of those with the disease and their families. Public awareness campaigns include Parkinson’s disease day (on the birthday of James Parkinson, April 11) and the use of a red tulip as the symbol of the disease. People with Parkinsonism who have increased the public’s awareness include actor Michael J. Fox, Olympic cyclist Davis Phinney and professional boxer Muhammad Ali.