Is addiction a brain disease?

A blog reader recently sent me this message:

First, it still seems like the act of drinking, smoking or doing other drugs is behavior and over time this behavior can lead to real health problems. Even by your own analogy, if someone were predisposed to heart disease because their father and grandfather had heart attacks because they smoked, never exercised and were overweight does not mean that you will have a heart attack especially if you exercise, eat properly and don't smoke. So, because someone is predisposed does not mean they are diseased. It would seem reasonable to suggest that addiction is a behavior that taken to the extreme over time can lead to very real organ and organ system impairment. This distinction I think is important because doctors that subscribe to the disease model and who state that addiction is a chronic progressive brain disease which you have clearly pointed out is not necessarily the case, imply this then with addiction is general. The person addicted to the Internet has a brain disease? The person addicted to their relationship has a brain disease? Studies on addiction are mainly about drinking which makes sense because substances do effect the brain. But, if I was a chronic Blackberry user, would I be damaging my brain and need rehab? The answers to these questions would be a great follow up to your response which you stated would require further responses any way.

There is a lot of confusion about the concept of a disease, especially when it comes to behavior. I think the primary problem is that we are not used to thinking of the brain as an organ, and we don't usually associate behavioral disturbances with brain dysfunction. A second problem is that of biological reductionism, where certain classes of phenomena (e.g., genomics, cell function, neurotransmission, etc.) are considered more real or important than other classes, such as thinking, feeling or behaving. We are used to thinking that if we are retaining too much fluid there might be something wrong with our kidneys, or if we have trouble breathing there might be something wrong with our lungs. We have no trouble believing that a brain tumor can produce seizures or paralysis. However, when it comes to more functional disturbances of the brain, our brains can't handle the idea. We think the mind and will are disembodied, existing in the ether out there somewhere, not attached to flesh and blood.

But this isn't true. Our minds, our wills, our thoughts, our feelings and our behavior all involve and depend upon proper function in the physical brain. For example, try thinking, feeling or doing something without a brain. It doesn't get you very far. Does this mean that these things are just biological machinations of this organ inside our heads? No, not at all. Does it mean that we are simply computer-controlled organisms living out our programmed lives? No. Does this mean that existential meaning, relationships, and spiritual striving are merely chimera? No, absolutely not. That's just it: Just because we require a brain for those things (and we do) does not mean that they are simply reducible to brain activity. To conclude so is to fall victim to biological reductionism.

I have been thinking about and studying these things for many years, and this is one of the toughest things I have ever struggled with. Here is my conclusion: one can study a living being at a multitude of levels, from genes to cells to organs to individual organisms to collections of living organisms such as a hive or city. Each level of analysis is valid in its own rite. None are fundamentally more valid than another, and they all influence each other constantly. These are systems of parts where the system is more than the sum of its parts, it is its own thing. A person, for example, or more than a collection of organs. A heart is more than a collection of cells, etc.

So, is addiction a brain disease? Well, addiction is a disorder of behavior so clearly the brain is involved. Are compulsive gambling, sexual activity or shopping brain diseases? They involve disordered behavior, so yes, the brain is involved. Are panic attacks or schizophrenia or depression brain diseases? Again the answer is that the brain is involved, and it must be dysfunctional in some ways for the disordered behavior to occur (by definition.) BUT, are they only and simplistically brain diseases? No they are not. Does brain involvement imply that they are pre-determined, not alterable, and not amenable to social influences, psychotherapy, will and effort or medication? No it does not.

You see, taken to its extreme, all disordered behavior involves the brain. Not only that, but the definition of “disordered behavior” is heavily culturally determined. For example, in Saudi Arabia drinking alcohol at all is “disordered” (except among the royalty), while cannabis or opiate use is much more normative. The opposite holds true for North America. Compulsive sexuality in the US might be considered normal male behavior in many other cultures. Drunkenness is almost a requirement in some Asian business environments whereas it has increasingly become stigmatized in the US. Another prime example is the gradual disapproval and stigmatization of smoking tobacco in the US. What was once a symbol of sophistication has become a symbol of lower class behavior, of “inferior” people who can't quit smoking and put on Lycra for their bike ride or run after eating granola and yogurt for breakfast. Now, the same is happening for obesity.

So the bottom line is that disordered behavior necessarily involves the brain because it cannot otherwise be possible. Ergo, the brain is disordered if behavior is disordered. However, brains can become disordered by hostile environments, extreme stress and many other outside influences. To say that disordered behavior is only the product of an individually “diseased” brain is to blame the victim in many cases. One cannot separate the internal environment, the brain, and the external environment. They are all part of the same organic system. Biological reductionism is therefore inherently politically reactionary: it places the problem squarely in a disordered individual, perhaps genetically inferior, while ignoring larger social influences that have substantial effects on individuals and therefore individual brains. More on this to come.