Thanks to a growing body of research, addiction is now understood as an acquired disease of the brain. But it’s a finding that many still have trouble wrapping their minds around.
And who can blame them? To those on the outside of the illness, addiction seems pretty straightforward: A person indulges too much in a substance that boosts their mood and doesn’t want to stop.
The reality, however, is that what can seem like moral weakness is actually a brain that has lost the ability to make good choices. It’s a neurobiological process that generally breaks down into three stages that overlap and fuel each other, according to an examination of the disease model of addiction published in The New England Journal of Medicine.
The overview — put together by a group of addiction experts headed by lead author Nora D. Volkow, MD, director of the National Institute on Drug Abuse — was published in the hope that it would help the public and policymakers better visualize the addictive process and, as a result, make them more willing to support a national response that moves away from judgment and toward more positive, science-based approaches to prevention and treatment.
The report emphasizes that not everyone who tries drugs becomes addicted, just as not everyone is at the same risk of developing a disease such as diabetes. Genetic, environmental and development factors all play a role. But in those who are vulnerable, addiction generally evolves like this:
Stage 1: Binge and Intoxication
Remember the story of Pavlov’s dogs, which were made to salivate at the sound of a dinner bell? In essence, the same is going on here.
When a person takes an addictive drug, a surge of dopamine is released and the brain’s receptors register it as a reward. With continued use, the brain’s dopamine cells start firing in anticipation of receiving the drug. The brain has learned to associate the reward with the environmental stimuli at the time, and that means all the cues of drug use — where you were, whom you were with, how you were feeling, the smell and look of the drug — can trigger powerful cravings and prompt a binge. It’s why hanging around those you did drugs with or walking past your favorite bar can be so dangerous to those trying to quit.
This conditioning becomes so ingrained that even in a person with years of successful recovery, cues can arise to trigger drug-seeking behavior.
Stage 2: Withdrawal and Negative Affect
As drug use continues, a disturbing thing happens: The brain adapts by resetting its reward system, dulling the ability of the person to experience pleasure from the drug or from the other things in life that used to motivate them, such as relationships and activities.
Not only that, drug use causes changes in brain circuitry that set in motion an overactive “anti-reward” system — boosting the person’s reactivity to stress and prompting negative feelings when the drug is withdrawn.
Eventually, the person is no longer using the drug to get high but to simply stave off cravings and the pain of withdrawal. It sets up a vicious cycle: The more the drug is used, the worse the cravings and withdrawal will be, which pushes the person to use more of the drug.
Stage 3: Preoccupation and Anticipation
As the addiction progresses, the person becomes more and more obsessed with their drug, even though their world may be crashing down around them and even though they may be desperate to stop.
The problem is this: Addiction not only affects reward circuits, it messes up signaling in the parts of the brain involved in executive functions such as self-regulation, decision-making and the ability to monitor error. Without these to rely upon, the desire to stop often becomes no match for the desire to use.
Addiction Treatment Advances
Despite the grim portrait, the report ends on an upbeat note, explaining that prevention programs that teach people self-regulation and social skills and help them understand their risks can be a powerful force in keeping them from taking that first pill or drink.
For those already struggling with a substance, a variety of evidence-based treatment approaches are being used successfully to help people reclaim their lives. These treatments recognize that the brain changes with addiction and more must be done than simply expect the addicted person to white-knuckle their way to recovery. They include:
- Multiple medications — including buprenorphine, naltrexone and others — that can help control cravings and symptoms of withdrawal, as well as help prevent relapse while brain circuitry has a chance to return to healthy function.
- Psychotherapies such as cognitive behavioral therapy (CBT) that can teach healthier ways of thinking and behaving.
- Behavioral interventions that teach ways to deal with stress and drug-related cues, and manage the negative feelings that can so often lead back to drug use.
A key reminder in the report is that waiting does nothing for addiction other than allowing it to proceed from one stage to the next and become more entrenched. “If early voluntary drug use goes undetected and unchecked, the resulting changes in the brain can ultimately erode a person’s ability to control the impulse to take addictive drugs,” it summed up. The sooner the person who is struggling with drugs or alcohol reaches out for help, in other words, the greater the chances that he or she will join the estimated 23 million people across the nation in successful recovery.
“Neurobiologic Advances from the Brain Disease Model of Addiction”
Nora D. Volkow, M.D., George F. Koob, Ph.D., and A. Thomas McLellan, Ph.D.
N Engl J Med 2016; 374:363-371 January 28, 2016 DOI: 10.1056/NEJMra1511480