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Which two parts make up the substantia nigra?
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The substantia nigra is composed of two distinct parts: the pars reticulata and the pars compacta.12
These two regions serve different functions within the brain:
* Pars compacta: Contains cells that synthesize dopamine and project to the caudate nucleus or the putamen.1
* Pars reticulata: Acts as part of the output system of the corpus striatum by projecting fibers to the thalamus.12