Parkinson's disease is a gradually progressive degenerative disorder of the central nervous system. Parkinson's disease belongs to a group of conditions called movement disorders. There are 4 characteristic problems caused by Parkinson's disease, including tremor at rest, balance problems, stiffness, and slowness of movement.

The Central Nervous System

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Parkinson's disease occurs when areas of the brain, including an area called the substantia nigra, is slowly destroyed. The exact reason for this destruction is not completely known. In some people, it may be related to genetics, environment, or a combination of both. The end result is a deprivation in the brain of an important neurochemical, called dopamine. Dopamine helps regulate movement, and its loss leads to increased tone, rigidity, and slowness of movement. Lack of dopamine results in the symptoms associated with Parkinson's disease.