Parkinsons disease is a degenerative disease of the brain as a result of which brain neurons are unable to produce dopamine when dopamine reduces in the brain it causes the emergence of symptoms of parkinsons parkinsons is a progressive disease though the rate of deterioration may vary in different individuals. Parkinsons is a disease of the nerve cells the brains neurons start to break down and die which can lead to a reduction in the amount of dopamine in the body when levels of dopamine decrease the brain activity becomes abnormal and you cant control your bodys functions and actions as well. Parkinsons disease is a progressive neurological disorder the first signs are problems with movement smooth and coordinated muscle movements of the body are made possible by a substance in the. What you need to know what is parkinson disease pd pd is a long term movement disorder the brain cells that control movement start to die and cause changes in how you move feel and act