Sometimes these diseases develop gradually over time. Some children with interstitial lung disease have other medical conditions such as heart disease, joint disease (arthritis), blood disorders such as sickle cell anemia, cancer, or chronic inflammatory bowel disease (such as Crohnâs or Ulcerative Colitis).
Peripheral neuropathy. I was diagnosed with Parkinson's one year ago. In December started having severe pain in my left leg. My primary care doctor just ordered a nerve study which confirms peripheral neuropathy.
In brief: A lot! Whole chapters in neuroanatomy are dedicated to the substantia nigra, but a short answer would be: it is indirectly involved with our muscle control including eye movement, and also the reward seeking/addictive, and learning aspects to our brain. When this part of the brain is damaged it causes parkinson's disease.