Parkinson's Disease

What Is It?

Parkinson's disease (PD) is a disease of the central nervous system. It causes problems with body motions, including:

  • Tremor (shakiness)

  • Rigidity (muscle stiffness)

  • Slowed body movements

  • Unstable posture

  • Difficulty walking

PD develops when certain nerve cells (neurons) in the brain die. These are neurons that produce a chemical called dopamine. Dopamine helps relay messages between areas of the brain that control body movement.

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