<P> The substantia nigra is a basal ganglia structure located in the midbrain that plays an important role in reward and movement . Substantia nigra is Latin for `` black substance '' , reflecting the fact that parts of the substantia nigra appear darker than neighboring areas due to high levels of neuromelanin in dopaminergic neurons . It was discovered in 1784 by Félix Vicq - d'Azyr , and Samuel Thomas von Sömmerring alluded to this structure in 1791 . Parkinson 's disease is characterized by the loss of dopaminergic neurons in the substantia nigra pars compacta . </P>
the midbrain includes the substantia nigra which is responsible for what
reward and movement