Parkinson’s disease (PD) is a neurodegenerative brain disorder. A disease in which there is a progressive loss of structure or function of neurons, including death of neurons.
Normally, there are brain cells (neurons) in the human brain that produce dopamine. These neurons concentrate in a particular area of the brain, called the substantia nigra. Dopamine is a chemical that relays messages between the substantia nigra and other parts of the brain to control movements of the human body. Dopamine helps humans to have smooth coordinated muscle movements.
When approximately 60 to 80% of the dopamine-producing cells are damaged, and do not produce enough dopamine, the motor symptoms of Parkinson’s disease appear. This process of impairment of brain cells is called neurodegeneration.
Parkinsonism is an inclusive term, which means that the patient has symptoms similar to Parkinson’s disease (like tremor, rigidity, slowness of movements and balance problems), although a doctor is not sure whether those symptoms are due to neurodegeneration of dopamine neurons in the substantia nigra. A number of patients with Parkinsonism do not have PD. Only 85% of all Parkinsonian syndromes are due to Parkinson’s disease. Certain medications, vascular problems, and other neurodegenerative diseases can cause the symptoms similar to Parkinson’s disease.
- Drug-induced Parkinsonism
- Progressive Supranuclear Palsy (PSP)
- Corticobasal Degeneration (CBD)
- Multiple System Atrophy (MSA)
- Vascular Parkinsonism
- Dementia with Lewy bodies (DLB)
Featured Image Source: http://www.webmd.com/parkinsons-disease/ss/slideshow-parkinsons-overview