What is Parkinson’s Disease?
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About Parkinson’s
What is Parkinson’s Disease?
Parkinson’s disease is a neurogenerative disorder that primarily affects movement. It develops gradually, sometimes beginning with a tremor in a single hand that is barely noticeable. However, while tremors are common, the disorder can cause stiffness, walking difficulties, etc.

The Role of Dopamine
When specific nerve cells (neurons) in the brain gradually degenerate or die, Parkinson’s disease results. The loss of neurons that make the neurotransmitter dopamine is the cause of many of the symptoms. Dopamine acts as a chemical messenger between brain cells to coordinate smooth and balanced muscle movement. Reduced dopamine causes aberrant brain activity, which impairs movement and results in other Parkinson’s disease symptoms.
What is Neurodegeneration?
The progressive loss of dopamine-producing neurons’ structure or function, including their death, is referred to as neurodegeneration. In Parkinson’s Disease, neurodegeneration primarily affects a region of the brain called the substantia nigra, that plays an important role in movement.
As neurodegeneration progresses, symptoms of Parkinson’s Disease emerge and worsen over time. One of the major causes of neurodegeneration is the presence of Lewy bodies (clumps of protein such as α-synuclein) in the brain cells. These clumps cause the death of dopamine-producing neurons and disrupt normal brain functions.


How Parkinson’s Affects the Brain
In Parkinson’s disease, the loss of dopamine-producing neurons mainly occurs in a region of the brain called the substantia nigra, part of a larger network known as the basal ganglia, which is responsible for controlling movement. As dopamine levels drop, communication between brain regions becomes disrupted, especially those involved in planning and executing voluntary movements.
But Parkinson’s doesn’t stop there. As the disease progresses, other areas of the brain—such as the cortex, brainstem, and limbic system—may also be affected. This wider impact helps explain symptoms that go beyond movement, like mood changes, sleep disturbances, and cognitive difficulties.
The exact mechanism of these widespread changes is still being studied, but it now known that abnormal protein accumulation of protein alpha-synuclein and chronic cellular stress as key contributors. These brain-level changes are what eventually lead to the complex set of symptoms experienced by people living with Parkinson’s.
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