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What are the symptoms of Parkinson's disease?
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The main symptom of Parkinson's disease is tremor, which is a shaking or quivering of the limbs. Other common symptoms include rigidity, slowness of movement (bradykinesia), difficulty with balance and walking (postural instability), stiffness in the neck, jaw, and back muscles (rigidity), and problems with speech and swallowing (dysphagia).