Although addiction has genetic, epigenetic, and environmental influences, it cannot be solely defined by any of these approaches. A new research article has showed how addiction is best described as an example of neural plasticity in the form of the brain’s ability to change and adapt to external stimuli. In other words, addiction is not just a patterned response; instead, the very process of becoming addicted actually rewires and changes the neural patterns of the addict’s brain.

Neuroscientist George Koob, director of the National Institute on Alcohol Abuse and Alcoholism in Bethesda, illustrated the concept well. “A lot of people think addiction is what happens when someone finds a drug to be the most rewarding thing they’ve ever experienced," Koob said. "But drug abuse is not just feeling good about drugs. Your brain is changed when you misuse drugs. It is changed in ways that perpetuate the problem.”

Such changes occur on both a physical and a mental level. Triggers are a neural response to sense stimuli. When an addict smells an odor associated with the addiction, they begin craving. Many addicts mention how the act of scoring would result in a need to go to the bathroom. By knowing the drug was coming, the brain reacted by fostering an almost physical purge of the body to clear the way.

Addiction also changes how the brain processes other rewards like money or sweets or sex, decreasing their relative value when compared to the power of the addiction. The neural plasticity adjusts and creates a hierarchy in terms of what is needed.

Once addiction takes over, connections between brain cells and between different areas of the brain strengthen and weaken.  The very act of taking the drug results in an immediate shift in the brain through neural plasticity.

“[There is] a whole series of plastic changes to those receptors, to the brain cells that connect with them," Koob said. "The more you do it, the more it becomes ingrained and permanent.”

The best explanation for addiction is that the brain is adapting to a new environment through neural plasticity. Such an adaptation takes place on many levels and impacts many behaviors, whether it is learning, reward, or emotional processing. As a result, in order to treat addiction effectively, it must be addressed from a multitude of angles and perspectives.