In Part 1 of this 2 part article we looked at some personality factors. In this, the conclusion, we will move to the biological factors of addiction.
I am pretty embarrassed to say this but I may have misled you on the title of the article. This second part is really more about the biology of addiction and the the vie addiction is a brain disease, rather than inherited genetic traits. I hope you still find it a good read.
The work comes from an interview is an edited transcript of an interview by Bill Moyers with Steven Hyman, M.D., on the brain and its role in addiction. Hyman directed the National Institute of Mental Health. Portions of this interview appear in the CLOSE TO HOME series.
Moyers: What are things like the PET scan and other brain imaging techniques doing for your research?
Hyman: Modern noninvasive neuro-imaging, PET scans, MRIs are very important. They’re allowing us to see the living, thinking, feeling, human brain at work. In the past, there were certain experiments that could only be done on animals. But there are lots of things we can’t ask a rodent or a monkey because they can’t describe their subjective experiences. These techniques allow us to take what we’ve learned from animal models and look at what happens in the human brain. What happens when we experience fear? What happens when we formulate a sentence or remember something? And I have to tell you it is really with a certain amount of awe that I experience some of the results that we’re getting.
Moyers: Can you look at these PET scans, these images, and see this communication taking place?
Hyman: Yes. We can image desire in the brain.
Moyers: What’s the most important thing we’re learning about addiction from brain research?
Hyman: Well, one very important insight is the recognition that in vulnerable individuals, the disease of addiction is produced by chronic administration of the drugs themselves. Drugs of abuse appear to commandeer circuits in the brain that are involved in the control of motivation, which means the addicted person’s will can be impaired.
Moyers: OK, now we’re back to addiction and the brain. So there’s solid evidence that alcohol, tobacco, cocaine, and heroin physically change the brain?
Hyman: There is incontrovertible evidence that these drugs physically change the brain. At all levels, beginning with molecular and chemical changes. In many cases we can actually see changes in the structure of synapses and in the shape of cells. Above all, what we’re seeing are the kinds of changes in the way nerve cells communicate with each other that would impact our subjective life and our behavior.
Moyers: You mean drugs change not only the physical size and shape of the cell but the psychological operation of the brain as well?
Hyman: Yes. The psychological operation of the brain — how we feel about ourselves, what we do — reflects the workings of networks of nerve cells. And these drugs change the way that these networks function. And therefore, they can change our behavior.
Moyers: There’s no natural high quite as high as a drug high?
Hyman: No, because the drugs really do trick the brain. Cocaine and amphetamine put more dopamine in key synapses over a longer period of time in this brain reward pathway than normal. And because they are so rewarding, because they tap right into a circuit that we have in our brains, whose job it is to say something like, “Yes, that was good. Let’s do it again and let’s remember exactly how we did it,” people will take these drugs again and again and again.
Moyers: His body is saying it wants more dopamine, he can’t get it, so he physically gets depressed.
Hyman: In effect, yes. But the addict doesn’t know that that’s what’s happening. What the addict knows, or thinks is correct, is, “I will feel better if I put myself back in this precise context where I felt good and use my drug.” This is the learning side of it, the emotional memory. It may not be true that taking the drug will make him feel better, but that’s what using the drug teaches him. And part of that memory is not only the emotion, but the whole context. The friends that they see when they are using drugs, the paraphernalia, the kind of room they are in or the kind of alley, all become attached to the ritual and the feelings of getting high. They become part of the brain’s “emotional memory.”
Moyers: That’s why AA talks about “people, places, and things.” Avoid the people you used with, avoid the places you used, and avoid the things associated with use like the pipe.
Hyman: That’s absolutely right. Remember, the dopamine in this brain reward circuit is still saying, “That was good, let’s do it again, and let’s remember exactly how we did it.” So there’s this emotional learning that goes on which is in many ways the longest lived change in the brain.
Moyers: Perhaps this is what we mean when we talk about indelible memories.
Hyman: I think that’s right. And one of the things that Alcoholics Anonymous says is that alcoholics are not recovered, they are recovering. I think they’re right because there are many things in the brain that make it likely that once addicted you’re at high risk of relapse and one of the most important is this indelible memory.
We know that when people are detoxified and then they’re back in a situation where they used to use drugs, they may experience certain feelings. In the case of the cocaine user, they might feel a little bit high. Which makes them want more. In the case of the heroin addict, some of them actually feel a little bit of withdrawal, and that makes them want the drug.
A common experience for ex-smokers is that they’ll have a festive meal and be reminded that they used to enjoy a cigarette at such times and they will feel waves of craving. These are cues which are awakening these powerful memories. When something is highly rewarding, we are likely to remember it vividly and also to remember the circumstances under which we encountered it. Even after years of abstinence, people may experience profound cravings and risk relapse if placed in the surroundings of their former drug use.
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I know that I did not answer the question posed definitively. It is your job to take what you need and leave the rest. I, personally, find it fascinating that many of the old beliefs and posits of Alcoholics Anonymous written 70 years ago are now being validated by science. All the AA old timers had going for them was intimate knowledge, keen intuition and good powers of observation. To read this interview in its entirety go to :
Addiction, A Disease:Brain Biology Questions And Answers That Are Easily Understandable. Part 1 of 3
Addiction, A Disease:Brain Biology Questions And Answers That Are Easily Understandable. Part 2 of 3
Addiction, A Disease:Brain Biology Questions And Answers That Are Easily Understandable. Part 3 of 3
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The determination of genetic risk is only a determination of higher risk toward the addiction and not necessarily an indication of future addiction. I think social factors have more effect on addiction than genetic (if there is a genetic addiction).