Parkinson's Disease is characterized by which of the following?

• A. Degeneration of basal ganglia in the brain and dopamine deficiency.
• B. Generalized brain degeneration causing mental deterioration.
• C. Demyelination of peripheral nerves.
• D. Inflammation of the meninges.

Answer: (A)

Parkinson's disease centers on movement control circuits in the brain. It results from the loss of dopamine-producing neurons in the substantia nigra, a component of the basal ganglia. Dopamine helps fine-tune movement, so when it’s deficient, the cortico-basal ganglia-thalamo-cortical loops become imbalanced, leading to the classic motor signs: tremor at rest, rigidity, slowed movement (bradykinesia), and a shuffling gait with a stooped posture. This combination—degeneration of the basal ganglia with dopamine deficiency—best fits the description. The other options describe conditions that affect different parts or aspects of the nervous system: generalized brain degeneration with mental deterioration points to dementias, demyelination of peripheral nerves occurs in diseases like multiple sclerosis, and meningitis is inflammation of the meninges.