Dopaminergic pathways

Dopaminergic pathways are neural pathways in the brain which transmit the neurotransmitter dopamine from one region of the brain to another. There are eight dopaminergic pathways, but the four major ones are:
 * mesolimbic pathway
 * mesocortical pathway
 * nigrostriatal pathway
 * tuberoinfundibular pathway

The mesolimbic pathway transmits dopamine from the ventral tegmental area (VTA) to the nucleus accumbens. The VTA is located in the midbrain, and the nucleus accumbens in the limbic system. The "meso-" prefix in the word "mesolimbic" refers to the midbrain, or "middle brain", since "meso" means "middle" in Greek.

The mesocortical pathway transmits dopamine from the VTA to the frontal cortex. The "meso-" prefix in "mesocortical" refers to the VTA which is located in the midbrain, and "cortical" refers to the cortex. Malfunctions of the mesocortical pathway are associated with schizophrenia.

The nigrostriatal pathway transmits dopamine from the substantia nigra to the striatum. This pathway is associated with motor control, and degeneration of this pathway is related to Parkinson's disease.

The tuberoinfundibular pathway transmits dopamine from the hypothalamus to the pituitary gland. This pathway influences the secretion of certain hormones, including prolactin. "Infundibular" in the word "tuberoinfundibular" refers to the infundibulum out of which the pituitary gland develops.

The neurons of the dopaminergic pathways have axons which run the entire length of the pathway. The neuron's soma produces the dopamine, which is then transmitted via the projecting axons to their synaptic destinations.

Reference

 * The Reward Circuit. Part of "The Brain From Top To Bottom".  The content of this page is copylefted and has been used in this article.