左边是Parkinson病人中脑黑质色素减少，右边对应的是正常中脑。与其他症状相比，临床上Parkinson病休息时出现很明显的球滚样颤抖、面具样面容以及齿轮样四肢僵硬。
The loss of pigmentation in the substantia nigra of the midbrain at the left in a patient with Parkinson's disease is contrasted with a normal midbrain at the right. Parkinson's disease is marked clinically by a "pill-rolling" tremor at rest, mask-like facies, and cogwheel rigidity of limbs, among other findings.