Low levels of
dopamine, a brain chemical involved
in controlling movement, cause symptoms of Parkinson's disease. Low levels happen when nerve cells in a part of the brain that makes dopamine break down. The exact cause of this
breakdown isn't known.
Scientists are looking for links between
Parkinson's disease and genetics,
aging, toxins in the environment, and
free radicals. Although
these studies are beginning to provide some answers, experts don't know the
exact cause of the disease.
Parkinson's disease is a movement disorder that progresses slowly. Some people will first notice a sense of weakness, difficulty walking, and stiff muscles. Others may notice a tremor of the head or hands. Parkinson's is a progressive disorder and the symptoms gradually worsen. The general symptoms of Parkinson's disease include:
Slowness of voluntary movements, especially in the initiation of such movements as walking or rolling over in bed
Decreased facial expression, monotonous sp...
Only a small
percentage of people with Parkinson's have a parent, brother, or sister
who has the disease. But abnormal
genes do seem to be a factor in a few families where
early-onset Parkinson's is common.
There are many other causes
of parkinsonism, which is a group of symptoms that includes tremor, muscle
stiffness, slow movement, and unsteady walking. Parkinsonism mimics Parkinson's
disease, but in fact is not Parkinson's disease.