What is Parkinson’s Disease Parkinson’s Disease or PD is a common and progressive brain disorder that results from degeneration of nerve cells in the portion of the midbrain that controls body movements. Occurring mostly in older adults that are over sixty years of age, the disease is characterized by gradual, progressive muscle rigidity, tremors and clumsiness. When Parkinson’s disease occurs, degenerative changes are found in an area of the brain known as the substantia nigra, which produces dopamine, a chemical substance that enables people to move normally and smoothly. Parkinson's disease is characterized by a severe shortage of dopamine. It is this deficiency that causes the symptoms of the disease. Parkinson's disease was first formally described in "An Essay on the Shaking Palsy," published in 1817 by a London physician named James Parkinson, but it has probably existed for many thousands of years. Its symptoms and potential therapies were mentioned in the Ayurveda, the system of medicine practiced in India as early as 5000 BC, and in the first Chinese medical text, Nei Jing, which appeared 2500 years ago. Symptoms of Parkinson’s DiseaseThere are several things to look out for as far as determining if one has Parkinson’s disease. Usually the first symptom is a tremor of a limb (trembling or shaking) especially when the body is at rest, not moving. The tremor usually begins at one side of the body, more frequently in one hand. Other common symptoms include a general muscle stiffness and slow movement, rigid limbs, an awkward or shuffling walk, and a stooped posture. People that are affected with Parkinson’s disease often show reduced facial expression or a complete loss of it and their voices change. It becomes soft. Their intellectual ability doesn’t change until the advanced stages of the disease, when it slowly deteriorates.Causes of Parkinson’s diseaseThe actual cause ...