Parkinson's disease is a progressively degenerative neurological disorder which affects the control of body movements.
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 per cent of the dopamine-producing cells are damaged, the symptoms of Parkinson's disease appear.
Symptoms result from the progressive degeneration of neuronal cells located in the substantia nigra. This causes a deficiency in the availability of dopamine; a chemical neurotransmitter (messenger) necessary for the production of smooth controlled movements.
The symptoms of Parkinson's disease appear when about 70 per cent of dopamine producing cells cease to function normally. Symptoms develop slowly and gradually progress over years, but are greatly helped by drug treatment.
Information courtesy of Parkinson's Australia.