This disease causes the person problems with carrying out movement. In 1817, Parkinson's Disease was thought to be a psychosomatic illness. Though James Parkinson wrote a paper proving otherwise. Parkinson's Disease is usually caused by the dying of the brain cells. These brain cells that are affected produce a chemical called dopamine.
Dopamine is the chemical that carries 'messages' from one nerve to the other.
The lack of dopamine affects the various muscle control that we used without thinking about. The first noticeable signs are tremors, unsteadiness, stiffness, and the decrease in movement. Some of these symptoms happen more often than others. Trembling hands usually occur when the person with Parkinson's Disease is resting or when there is a minimum movement. The person might have problems walking or with their balance.