Parkinson's Disease Definition
Definition
Parkinson's disease (PD) is a progressive movement disorder that causes:
- Muscle rigidity
- Tremor at rest
- Slowing down of movements (bradykinesia)
- Difficulty moving and gait instability
It is caused by a loss of nerve cells in the brain. This includes loss in an area called the substantia nigra . The loss decreases the amount of dopamine in the brain. Low dopamine results in PD symptoms.
Substantia Nigra—Yellow Section
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