:: Home

National Science Teachers Association
nervous system guide

Parkinson's Disease

Many people associate the tremors and shuffling gate of Parkinson's disease with old age. While this disease of degenerating muscular control is more common in the elderly, it can strike people of any age. Doctors have associated it with repeated injuries (like those a prize fighter might endure) or brain infections. They also know that there is a genetic predisposition to the disease. But most cases of Parkinson's disease remain a mystery to science.

In Parkinson's, the brain gradually loses control of the muscles. Cells in an area of the brain called the substantia nigra die or become impaired; these are the cells that produce a neurotransmitter named dopamine, which coordinates the millions of nerve and muscle cells involved in movement. The first symptoms are often subtle - a movement that becomes different or a mumbling speech. The delicate coordination of opposite muscles which enables a long, smooth stride is often lost. The hands may tremor or the voice quaver. Without treatment, the disease is progressive and devastating.

Some drugs, like L-dopa, can slow the progress of Parkinson's disease. But it becomes less effective over time. Deep brain stimulation with an implanted device somewhat like a pacemaker has had positive results in some patients. But the real cure will come when researchers can pinpoint why the body gradually destroys its own most basic brain functions and can stop the disease in its tracks.

::   Site credits: National Science Teachers Association,
     Medtronic Foundation