substantia nigra of the midbrain and its dopaminergic neurons in normal state and in parkinson's disease, 3d

substantia nigra midbrain 3d brain illustration system anatomical medicine anatomy black concept conceptual degeneration medical dementia destruction isolated development neurology disease disorder dopaminergic inflammation nervous model multiple atrophy parkinson nerve cell neurodegeneration neurodegenerative neurological neuron neuronal neurone alzheimer pars compacta huntington progressive wooden chest syndrome substance basal ganglia levodopa