Addiction: Could it be a big lie?

Go ahead. Judge drug addicts. Call them selfish. A Harvard psychologist gives you permission.

You do not have to be mean to them, he says. Just do not treat them as if they have some sort of, you know, illness.

Gene M. Heyman's book Addiction: A Disorder of Choice comes out this week. Like several other books released this decade, it disparages the overwhelming scientific consensus that addiction is an involuntary disease. Supporters of the overwhelming scientific consensus are not amused.

"His argument crashes and burns," says Tony George, the head of addiction psychiatry at the University of Toronto. "I don't think there's too many self-respecting scholars in the addiction field who would agree with him. I'm shocked that Harvard University Press would publish that."

"These guys – I don't know, academia, they just kind of take what they want, and they don't care about the truth, or what the studies show," says Norman Miller, a professor of medicine at Michigan State University.

"What aspect of disease," says Norman Hoffman, a psychology professor at Western Carolina University, "does he not understand?"

Heyman, a Harvard lecturer in psychology, did not expect to be lauded by the medical-scientific establishment. His book indicts its members. Appealing to an eclectic mix of studies and examples – Philip Roth's impotent alter ego Nathan Zuckerman makes a brief appearance – he attempts to persuade us that we have been persistently deceived by so-called addiction experts who do not understand addiction.

If hardly a controversial topic to those other than the small group of dissidents who want it to be, the semantic disease-or-not debate has important practical implications. How addiction is viewed affects how addicts are treated, by the public and by medical professionals, and how government allocates resources to deal with the problem. Heyman, who says he was once reluctant to share his conclusions, now makes his case forcefully.

Can humans be genetically predisposed to addiction? Sure, he writes, but this does not mean addicts' drug use is not a voluntary behaviour. Are addicts self-destructive? Of course, he writes, but this does not mean they do not respond to the costs and benefits associated with their decisions, even when addiction has changed their brains. Is addiction a chronic, lifelong disorder? No, he concludes. Most experts, he argues, do not understand just how many addicts quit for good.

Addiction draws heavily on behavioural economics, a field that fuses psychology with economic theory to predict human behaviour. The book is complex.

It is fundamentally based, however, on that last, simple point: Addicts quit. Clinical experts believe addiction cannot be permanently conquered, Heyman writes, because they tend to study only addicts who have entered treatment programs. People who never enter treatment – more than three-quarters of all addicts, according to most estimates – relapse far less frequently than those who do, since people in treatment more frequently have additional medical and psychiatric problems.

Miller says Heyman has misinterpreted the data to which he points. George says studies of non-treatment-seeking people contradict Heyman's conclusions. Says Hoffman about those conclusions: "Yeah, so?"

Many addicts, Hoffman agrees, can indeed quit of their own volition. But some people live long lives with cancer. This is not proof that cancer is not a disease, he says, merely that some people suffer from more severe cases of diseases than others.

"If you compare Type 2 diabetes to Type 1 diabetes, one is much more virulent, more difficult to control. But we call them the same; we call them both diabetes," he says. "Since we're talking about a plethora of genes involved in addiction, we may also be looking here at a variety of illnesses that we're labelling the same but are really very different."

Heyman concurs with the expert consensus on the nature of addicts' thinking at the time of a relapse. The addict, he writes, does not choose to be an addict; he or she merely chooses to use the drug one more time, nothing more, and thus ends up an addict unintentionally.

The question is why the addict chooses to use the drug one more time. "The evidence from neuroimaging, animal studies, genetic association studies, clinical trials, is overwhelming," says George: The addicted brain is a changed brain. It is simply incapable of resisting a desired drug. But Heyman argues that addicts with sufficient self-control can organize their lives so that they are not directly confronted with an abstain-or-succumb decision.

People who have stronger incentives to remain clean, such as a good job, are more likely to make better lifestyle choices, Heyman writes. This is not contentious. But he also argues that the inability to resist potentially harmful situations is a product of others' opinions, fear of punishment, and "values"; it is a product of a cost-benefit analysis.

He does not dispute that drug use alters the brain. He does not dispute that some people have genes that make them more susceptible to addiction. He disputes that the person who is predisposed to addiction and the person whose brain has been altered are not able to ponder the consequences of their actions. In other words, he disputes that biological factors make addicts' decisions compulsive.

This is where the experts he maligns begin to grumble again. In the changed brains of many addicts, says George, the capacity for voluntary behaviour with regard to drugs has been overwhelmed. It is as if the brakes that might allow them to stop before using have ceased functioning.

While addicts may not ignore the consequences of their actions, many – even people with families, good jobs and a lot to lose – are unable to make those consequences the basis for their actions.

"Where (Heyman) loses the argument," George says, "is that there are clearly both biological and environmental or contextual factors involved, but he's basically saying that the context and the environment are everything and the biology is irrelevant. Well, what we know about the brain, and the brain on drugs, is startling."

Heyman knows he is a heretic. The book jacket on Addiction calls his thoughts "radical"; in the book, he writes that "most people believe the disease interpretation of addiction is the scientific, enlightened, and humane perspective." Changing minds will be difficult.

Then again, some people manage to quit drugs.