Our movements are controlled by nerve cells (neurons) in the brain which pass messages to one another, and to the rest of the body, using chemicals called neurotransmitters. An area of the brain called the substantia nigra produces one of the neurotransmitters that controls movement: dopamine. In people with Parkinson’s, 70-80% of dopamine-producing cells gradually deteriorate and are lost – this is called neurodegeneration.
The loss of dopamine-producing neurons results in low levels of dopamine in the part of the brain that controls movement and balance. When nerve cells do not pass on brain messages properly, movement is no longer controlled smoothly and the symptoms of Parkinson’s appear.
While dopamine is the main neurotransmitter involved, others are also affected. This may explain why simply replacing dopamine does not necessarily cause improvement. It may also help to explain why so many people with Parkinson’s also experience non-motor symptoms.
As yet there is no cure for Parkinson’s, but there are many things you can do to positively influence the course of the disease and enhance your quality of life. Maintaining a positive approach seems to slow down the progression of symptoms and helps you to stay in control.
Parkinson’s is life-altering, but not life-threatening. Some of the more advanced symptoms may make you more vulnerable to infection, but for most people, Parkinson’s will not significantly reduce life expectancy.