Dopamine is a neurotransmitter, one of those chemicals that is responsible for transmitting signals in between the nerve cells (neurons) of the brain. Very few neurons actually make dopamine. Some, in a part of the brain called the substantia nigra, are the cells that die during Parkinsons disease. The functions of others, located in a part of the brain called the ventral tegmental area (VTA), are less well defined and are the major source of the aforementioned controversy (and the focus of this post). When dopamine neurons become activated, they release dopamine.