Parkinson disease is a movement problem of the brain and spinal cord. It worsens over time. Hallmark problems are shaking, stiffness, balance problems, and slowed movements.

The Central Nervous System

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Parkinson disease happens when there is a breakdown of nerve cells in part of the brain. It is not known why this happens. It may be due to genes, the environment, or both. The nerve cells cannot make dopamine, a chemical that helps regulate movement.


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Last reviewed November 2019 by EBSCO Medical Review Board Rimas Lukas, MD  Last Updated: 1/26/2021