I was wrong.

For years, my advice to people seeking guidance about addiction was to avoid trying to explain it except in the simplest of terms: It is a chronic illness, a drug is a drug is a drug, and no matter the cause, the only way to address it is with professional treatment and personal responsibility on the patient's part.

I still believe those things. But this week, I came to a new understanding of the complexities of addiction to alcohol and other drugs. I listened to scores of scientists, researchers, scholars and government leaders discuss the science of addiction at the College on Problems of Drug Dependence symposium in Puerto Rico. And what I discovered is that a lot of them know more about how my brain worked (or didn't) on drugs than I ever did. No wonder I lived to get high and then got high to live even when those drugs were killing me in the 1980s.

"The brain is a complex organ, and when drugs of abuse are introduced into that organ, those dynamics become even more complex," said Dr. Nora Volkow, director of the National Institute on Drug Abuse. "It is a never-ending challenge and an opportunity, as well, to understand how these drugs affect the brain and how we can better treat the disease in this context."

Brain science may be of no interest to parents whose children are addicted or even to addicts and alcoholics whose baffling inability to "just say no" is destroying their lives. But I believe it is time to harness what these experts know in order to validate addiction's power and to explain what it is better and what to do about it.

Dear Mr. Moyers: Like you, there was a time in my life that getting high was fun. It isn't anymore. Now I can't seem to stop except when I run out of money after a long binge. Payday approaches, I get "thirsty," and all I think about is getting high. Do it or not do it; the mental anguish is excruciating. So I always end up going back to the dope dealer, and it starts all over again and ends the same way: I hate myself and my life. I'm a smart person with a lot of grit. But forget it when it comes to dope. Why can't I get off this stuff? It's killing me. — Tom N. in Denver

Dear Tom: The phenomenon of craving is a classic characteristic of drug addiction. Yet it still is misunderstood. To people like us, it seems to emanate from a place deep within our souls, an insatiable appetite fueled by a sharp euphoric recall to climb back to the high point of our most recent buzz. But in fact, it really comes from specific spots in our brains where nerve receptors altered by cocaine misfire in an automated effort to release a substance called dopamine. No amount of willpower alone can counter this activity. The good news is that brain function usually returns to normal after a short time to deliver regular jolts of dopamine. Treatment programs and some doctors now are using newly developed pharmaceutical therapies to help alleviate cravings. Group therapy, counseling and exercise are helpful tools, too. Avoid people, places and things that might be triggers, and most importantly, don't try to go it alone.

Dear Mr. Moyers: If alcohol is a depressant, why do I love to drink it so much? It always makes me feel good. Even when I drink too much and get sick or black out or get the shakes, I always return to the wine bottle. What is happening to me? Am I going crazy? — Susan K. in Stillwater, Minn.

Dear Susan: Indeed, alcohol is a depressive drug. In the brain, it actually reduces the production of a naturally occurring neurotransmitter, or chemical that connects nerve signals. The result is a decrease in physical and mental activity that makes you feel relaxed at first. But as you note, invariably it gets worse, especially for people who drink alcoholically and cannot stop despite the consequences. You are only crazy if you do not seek help.

William C. Moyers is the vice president of external affairs for the Hazelden Foundation and the author of "Broken," a best-selling memoir. The paperback edition was released in August 2007. Please send your questions to William Moyers at William@WilliamMoyers.com. To find out more about William Moyers and read his past columns, visit the Creators Syndicate Web page at www.creators.com.

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