progressive central nervous system degeneration or parkinson's disease

substantia nigra dementia parkinsons disease neurodegenerative depression psychiatry migraine motor neuron multiple sclerosis nerve cell nervous elderly system network stroke alzheimer neurology medicine schizophrenia palsy parkinson autism brain brainstorm cerebral mental shaking conceptual anxiety medical disorder dopaminergic epilepsy impulse bipolar mind sciatica anatomy senior patient health care diagnosis disability treatment memory sick