Anyone who looks at the Addiction blogs on the Psychology Today website recognizes there are widely disseminated but vastly different views about the very nature of addiction. When I give lectures about addiction, I am sometimes asked, "With all these opinions, how can I tell who is right?" It turns out that there is a surprisingly straightforward way to figure this out.
To set the stage: As I've discussed and illustrated in this blog and my books on addiction, addiction is a psychological symptom like other common symptoms that we call compulsions. While physical dependence is quite real, it cannot explain the clinical picture of addiction: the recurrence of addictive behavior years after physical dependence has faded, the frequent substitution of non-drug addictions for drug addictions, and so forth.
The major alternate view, presented by neurobiologists, is that addiction is a "chronic brain disease" caused by taking drugs that change the brain in a way that makes people excessively seek more drugs.
Now, when two sides debate, we judge which side to believe based on their expertise - their knowledge and experience of the issue at hand. If a chef debates a nuclear engineer about nuclear physics, we believe the engineer. If the topic shifts to the best way to cook a duck, we believe the chef.
We also want to know whether each side has studied the other's position. Generally speaking, if Side A doesn't know the basis for Side B's viewpoint, we should dismiss Side A for basing its conclusions only on its own perspective. How believable are they if they aren't aware of the errors or limitations others have identified?
On the subject of addiction, let us first consider the question of expertise. Neurobiologists who study drug effects on the brain have devoted their professional lives to studying just that. They have both training and experience in the anatomy and physiology of brains, and their work largely consists of conducting laboratory experimentation on animal brains (mostly rats). It is therefore reasonable to believe what they say about how these animal brains work and how they are affected by drugs. But these scientists typically have little or no experience treating people, and their training is not mainly devoted to human psychology. (Even those neurobiologists who are psychiatrists have chosen this career path largely in place of clinical work with patients.) This has resulted in a fundamental problem with the neurobiological theory: it takes findings with rats and generalizes them to humans. It is a leap that would never be made by people who have training and experience with addictions in people.
To those familiar with addiction in human beings, it is obvious that the "addictive" behavior observed in rats is nothing like the behavior of people with addictions. When rats have long-term exposure to opiates, they increase seeking behavior in response to cues associated with the drugs, just as in Pavlov's famous dogs. But the changes in rats' brains that lead them to automatically seek drugs when exposed to cues either do not occur in humans, or if they do occur, do not produce addictive behavior. As I have described elsewhere in this blog, a massive body of evidence has proven that exposing people to drugs for long periods does not turn them into addicts as the "chronic brain disease" theory would predict. And addiction in humans looks very little like rat behavior in a number of other important ways:
Let's now consider the question of expertise on the psychological side of the debate: people who treat human beings with addiction. For myself, I have trained extensively in human psychology, first as a psychiatrist and then as a psychoanalyst. I have devoted my career to treating people, as director of major addiction treatment programs involving thousands of people where I treated and supervised the treatment of many of them myself, and in my individual psychotherapy practice for over 35 years. I have written many academic papers and books about the psychology of addiction. This is the training and experience behind my views about human addiction.
But what about the other big criterion we use to evaluate an argument: understanding the other side's facts and logic? Although my interest is in human psychology, I read the neurobiological literature. In 2009 I published an academic paper on the respective roles of neurobiology and psychology, referencing and describing the neurobiological view and explaining where it is applicable and where it falls short.
It is possible that some of the leading neurobiologists have read the psychological literature, but I can tell you that I have not found any sophisticated consideration of the psychology of addiction in any of the neurobiological addiction literature (and I am a reviewer for more than one addiction journal). What passes for psychological insight (if it appears at all) is questionnaires about general traits like "interest in risky activities." This absence of sophistication quite simply makes it impossible for the authors to recognize or meaningfully engage the psychology behind addictive behavior.
So, who is right? I offer this rule of thumb: for questions about how drugs affect brains and where in the brains drugs act, believe the scientists who study those issues. For understanding addiction in humans, believe those who have experience and training with humans. If still in doubt, remember that human addictive behavior is vastly different from the behavior called "addiction" in rats which is the basis for the neurobiological view.
One final point. Some authors like to split the difference and say addiction (in humans) is both psychological and neurobiological in origin. This approach tends to make everyone feel good. However, since the "chronic brain disease" idea doesn't apply to people, it isn't good science to include it in the explanation.