Addiction: The Battle for Brain Control

substance abuse addiction disease model

Maybe you’ve been there…you’ve had friends or loved ones who chronically drink a few too many, or who somehow still rely on that pain medication they were given post-surgery—and wasn’t that procedure eight months ago? You’ve heard it before—their plans to kick the habit. This time, they insist, they’ll really do it. But increasingly, you’re concerned about their long-term health, alarmed that their habit seems to dominate their life. And finally, you’ve lost your cool and demanded, “Why can’t you just get your act together and quit?”For observers, it can be tempting to simply attribute such unhealthy habits to some moral failing, some weakness of character. But that explanation, addiction experts say, wouldn’t begin to capture the whole picture. That’s because what you’re witnessing is likely much more than a series of poor choices or weak moments. The situation may be a true battle with addiction, a chemical phenomenon that addictive substances cause in the brain, and depending on how firmly it takes hold, character strengths like willpower can be rendered all but useless.

“Disease model” 
Doesn’t Blame the Addict

As far back as the 1950s, the American Medical Association named addiction a disease, and this so-called “disease model” of addiction, rather than a moral view that blames the addict, is the prevailing view today, according to Rick Gressard, a professor of addictions counseling at The College of William & Mary, with 35 years’ experience in the field. He is also faculty director of New Leaf Clinic, a clinic for students at the college with issues related to substance abuse. “Practically speaking,” he says, “the disease model is probably our best way of looking at addiction.”
Understanding the mechanism of addiction requires keeping in mind two factors, Gressard says. The first is neuroadaptation, or the adaptability of the brain, which has been shown to be constantly changing and exceedingly adaptable to new circumstances. The second is what is known as the brain’s reward pathway. As a survival mechanism, Gressard says, the brain seems to naturally draw us to substances or activities that help keep us healthy. These trigger the release of dopamine, a chemical neurotransmitter, from a part of the brain stem known as the “pleasure center.” This surge of dopamine creates a feeling of well-being.

Dr. John Colaluca, medical director at The Farley Center at Williamsburg Place, which runs both outpatient and residential programs for patients struggling with drug or alcohol abuse, explains it this way: “The aim of the normally functioning human brain is to acquire food, shelter, sex, water, air—all things that, with a certain amount of dopamine release, register as being pleasurable. These things register as good, and for my survival.”

What addictive substances do, however, is hijack the brain’s normal reward pathway, also acting on the brain’s pleasure center receptors and creating a comparable jolt of dopamine. The result? That unhealthy, potentially dangerous substances create an enjoyable feeling that users want to feel as often as possible.

Dopamine:
 The True Addictive Chemical

That’s why, contrary to the customary thinking about substance abuse, “the main addictive chemical isn’t really the one a person is using,” Colaluca says. “It’s actually dopamine.”

All addictive substances—Colaluca names examples such as alcohol, amphetamines, the anti-anxiety medication Xanax, pain medications known as opiates—create this feel-good release of dopamine. And Gressard adds that certain activities, such as gambling and sex, can become addictive because they also produce this effect. And when the brain has increased access to dopamine that outside sources help generate, it gradually adapts, producing less on its own and becoming hungry for the dopamine produced by addictive substances. The result, Gressard says, is that “first you have to keep using a drug to feel good, and then, you have to keep using the drug just to feel normal, and not feel bad. Why do people crave [what they’re addicted to]? Because their brain is screaming, ‘Give me dopamine!’ 
It’s a vicious cycle.”

Most importantly, says Colaluca, substance abuse and its effect on brain chemistry “change the brain’s priority system, and it now becomes more important [for example] to acquire heroin, and more important to use heroin, than it is to have a place to live.”

An addiction’s chemical takeover of the brain can have powerful ramifications for an addicted person’s behavior and life choices, which will be explored in the continuation of this series in next month’s issue.

About the author

Beth Shamaiengar

Beth Shamaiengar is a contributing editor at Health Journal. She holds a Bachelor’s degree in Journalism from the University of North Carolina at Chapel Hill and, before joining the Health Journal, became an award-winning writer and editor during 11 years with other publications. She also spent nearly a decade volunteering in PTA leadership roles in local schools, building her skills in marketing, event planning, project management and communicating with a variety of audiences. She also enjoys supporting the arts, writing poetry, and spending time with her husband, two sons, and two cats.