THE SOBER TRUTH: Debunking the Bad Science Behind 12-Step Programs and the Rehab Industry. By Lance Dodes, M.D., and Zachary Dodes. Beacon Press. 179 pages. $26.95.

Did you know that the most widely accepted treatments for alcohol and drug addiction, Alcoholics Anonymous and similar programs, rest on the flimsiest of scientific evidence? I didn't. That and more are what psychiatrist Dr. Lance Dodes and son Zachary Dodes claim in this polemical and deeply flawed book about the nature and treatment of addiction.

It was Alcoholics Anonymous, of course, that developed the famous 12 steps, in which an addict admits to being powerless, submits to a higher power and recognizes all manner of personal failings. Enormously popular with the public and the medical establishment, AA became the gold standard for treating alcoholism.

The group claims that up to 75 percent of its members maintain abstinence, but since it does not conduct outcome studies or publish its dropout rates, it is hard to gauge its true efficacy. And the authors are highly skeptical of its claims; they note, for example, that a randomized clinical trial in The New England Journal of Medicine in 1991 showed that patients assigned to AA did less well than those treated in hospitals, and that a 2006 Cochrane review concluded that the program's effectiveness was unclear and needed further study. They suggest that it might help only a subset of those who walk through the door.

Even if one grants that AA and 12-step programs are helpful only to those patients who adhere to them, surely that is better than nothing. But the Dodeses' indictment goes much further: They tell readers that the public has been misinformed by the biological research community, and that addiction cannot be understood in terms of altered neurobiology, but as a pure psychological compulsion that helps addicts deal with feelings of helplessness.

The evidence for this theory?

One anecdote of a patient named Marion whose rage at having to cater to her demanding husband led her straight to the medicine cabinet; and a citation of Dodes' own paper in a psychoanalytic journal, which is a theoretical discussion of two more patient anecdotes.

"The Sober Truth" asserts that addiction can be treated with psychodynamic psychotherapy, which focuses on unconscious feelings and thoughts.

While there is some scientific data for cognitive behavior therapy in addiction, there is little to no evidence that psychodynamic therapy is effective for any type of drug abuse. The authors' claim of efficacy for their own treatment, in the absence of credible data, is the very flaw for which they criticize AA.

This simplistic and unitary model for addiction ignores much of clinical reality: drug abuse driven by novelty and sensation-seeking, which is typical of adolescents; and the high prevalence of substance abuse in patients with depression and anxiety disorders, most likely a result of efforts to self-medicate.

(Moreover, readers will not learn from this book that there are effective biological treatments that help decrease drug craving and reduce relapse.)

But the book's most glaring deficiency is the authors' dismissive attitude and misunderstanding about the role of neuroscience in addiction. Most people who experiment with drugs do not become addicted.

Why? In part because there are important biological differences between those who fall to addiction and those who don't.

Several brain-imaging studies of people addicted to drugs suggest that they have fewer dopamine receptors in the brain's reward pathway than do nonaddicts. Dopamine is critical to the experience of pleasure and reward, so addicts may simply have a lower baseline level of happiness than other people. Other studies comparing the response of addicts and control subjects to an infusion of stimulant show that the addicts with low levels of dopamine receptors found it pleasurable while those in the control group disliked it.

These kinds of studies clearly show that neurobiology plays an important role in vulnerability to addiction, even if they cannot tell us its ultimate cause.

Still, addiction is one of the most puzzling and fascinating human behaviors, one that reflects a complex interplay among genes, biology, psychology and environment. Those looking for a scientifically accurate and nuanced understanding of addiction and its treatment will not find it in this book.