Parkinson's disease

n. Parkinson's disease is a disease of the nervous system characterized by trembling arms and legs, jaw tremors, muscle rigidity, unsteady balance, general slowing of voluntary movement, and sometimes speech impairments. Parkinson's disease is marked by the death of certain nerve brain cells. These cells are responsible for the production of dopamine, and the death of these cells results in reduced supplies of dopamine and subsequent loss of muscle control. Unfortunately, as these nerve cells continue to die off, the symptoms of Parkinson's disease worsen over time.

The precise cause of the atrophy and death of these cells is unknown, but researchers have proposed that a combination of genetic predispositions, mutations, and environmental toxins may be responsible for the onset of the disease. Researchers have noted that the disease is often mistaken as part of the normal aging process or may be misinterpreted as being symptomatic of other diseases. It often takes several years for an individual to develop new symptoms that might alert doctors that the patient is experiencing something more profound than the normal aging and loss of motor skills. The uncertainty of cause and delayed diagnosis add to the difficulty in understanding the onset, development, and treatment of the disease. Additionally, the disease does not present uniformly across individuals. The onset can be either sudden or slow, and the typical symptoms of motor difficulties are sometimes accompanied by symptoms of anxiety, depression, or impaired reasoning. Occasionally, persons with Parkinson's disease later develop dementia.

Currently, Parkinson's disease can often be distinguished from other possible diagnoses on the basis of the patient's response to drug treatments. Persons with Parkinson's disease often respond more positively to the prescribed medications than do persons experiencing symptoms due to other causes. While none of the drugs provides a cure for Parkinson's disease, it has been possible for doctors to control the symptoms and slow decline. – TJM