Most researchers agree that the key difference between human brains and those of other animals is the size and complexity of our cerebral cortex, the brain’s outer layer of neural tissue. We therefore tend to focus our attention on this area, believing that our unique mental life is due to this masterpiece of evolution.
But we often ignore the bits that are nearly identical between humans and animals, such as the tiny group of brain cells that use the chemical dopamine to communicate with other brain cells.
As I understand it, there are dopamine-related addictive substances such as PCP and cocaine. There are drugs such as Heroin, morphine, and other opiods that bind to an opiod receptor in the brain, totally apart from dopamine.
“The projections from the ventral tegmental area (VTA) are a network of dopaminergic neurons with co-localized postsynaptic glutamate receptors (AMPAR and NMDAR). These cells respond when stimuli indicative of a reward are present. The VTA supports learning and sensitization development and releases DA into the forebrain.[43] These neurons also project and release DA into the nucleus accumbens,[44] through the mesolimbic pathway. Virtually all drugs causing drug addiction increase the dopamine release in the mesolimbic pathway,[45] in addition to their specific effects.”
