Correlation 3: Parkinson's Disease

Note the abnormal midbrain on the left, with decreased pigmentation of the substantia nigra in a patient with Parkinson's disease, compared with the normal midbrain with pigmented substantia nigra on the right.

The substantia nigra of the midbrain normally contains many large pigmented neurons which participate in a variety of neural connections that help to control movement. In Parkinson's disease (PD), these pigmented neurons are lost. Almost all cases of PD are termed "idiopathic" PD. The term idiopathic is used when we do not know the cause. Persons with Parkinson's disease are typically middle aged to older adults. They have movement disorders including tremor, difficulty walking, and an expressionless ("mask like") face.