Parkinson's disease is a degenerative nervous system disorder affecting movement and belongs to a group of conditions called motor system disorders.
It affects an area of the brain known as the basal ganglia which is responsible for regulating movement and coordination. Chemical neurotransmitters send signals to and from the basal ganglia. One of the main neurotransmitters involved is dopamine.
Parkinson's disease causes the degeneration of nerve cells in the basal ganglia which causes decreased production of dopamine.
The most noticeable characteristic of Parkinson's disease is tremors or shaking when standing, sitting or lying still.
Parkinson’s disease is both chronic and progressive, meaning that it worsens over time. It may eventually affect other aspects of brain function as the illness worsens.
In general, dopamine does not significantly affect life expectancy. Parkinson's disease usually does not affect intellect, however some patients do develop dementia.
Revised and reviewed by Prof Carr February 2015. Reviewed by Dr Andrew Rose-Innes, MD, Department of Neurology, Yale University School of Medicine, New Haven.
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