Parkinson’s disease (PD) is a type of movement disorder that can affect the ability to perform common, daily activities. It is a chronic and progressive disease, meaning that the symptoms become worse over time. It is characterized by its most common of motor symptoms—tremors (a form of rhythmic shaking), stiffness or rigidity of the muscles, and slowness of movement (called bradykinesia)—but also manifests in non-motor symptoms including sleep problems, constipation, anxiety, depression, and fatigue, among others.

Who does the disease affect?

There are an estimated 1 million people in the U.S. living with Parkinson’s disease and more than 10 million people worldwide. Most people who develop the symptoms of Parkinson’s disease do so sometime after the age of 50, but Parkinson’s disease can affect younger persons as well. Approximately 10% of Parkinson’s diagnoses occur before age 50.

How does Parkinson’s disease affect the brain?

Explaining the Science Behind Parkinson’s Disease

What makes Parkinson’s disease distinctive from other movement disorders is that cell loss occurs in a very specific region of the brain called the substantia nigra (sub-STAN-she-uh NYE-gruh). The nerve cells, or neurons, in this region actually appear dark under a microscope (substantia nigra is Latin for “black substance”).

Those dark neurons produce a specific type of neurotransmitter (a chemical messenger that allows neurons to communicate) called dopamine. The neurotransmitter dopamine helps to regulate movement. This loss of dopamine is the reason that many treatments for Parkinson’s Disease are intended to increase dopamine levels in the brain.

The exact cause of Parkinson’s is still unknown, but there is an enormous amount of research being done to learn more. While there is no definitive test that can be taken to determine whether a person has Parkinson’s disease, movement disorder specialists look for symptoms and use brain imaging technology to accurately diagnose Parkinson’s.

As of today, there is no cure for Parkinson’s disease. But there are many ways in which the disease can be treated to make symptoms more manageable. It’s possible to maintain an active and positive lifestyle through healthy choices, medical assistance, and support from your family, friends, and community.

For more information, visit