Neurotransmitters, are molecules that act as messages in the nervous system.
Dopamine is one of several neurotransmitters.
The dopamine system is roughly divided into the three sources. The ventral tegmental area projects to the frontal lobe of the cortex, and it is associated with Schizophrenia and reward systems. The substantia nigra projects to the striatum, and its failure to produce enough dopamine is correlate with Parkinson's disease; this system affects fine motor control. The basal hypothalamus projects to the neuroendocrine cells, which regulate posterior pituitary functions, including prolactin secretion.
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