May being mental health month, I thought it timely to discuss one of the most costly mental health issues we face today: addiction.

Addiction exacts a huge toll on our society. In purely monetary terms, the National Institute of Drug Abuse estimates that addiction to alcohol, tobacco, and illegal drugs costs the U.S. $559 billion a year. This price tag results from increased health care costs, decreased productivity, and crime, and does not even include the cost of prescription drug abuse, which is on the rise. And as anyone who has experienced addiction up-close can attest, the personal costs of addiction are enormous. Addiction destroys families and lives.

If we want to fight addiction, it almost goes without saying that we need to understand it: what causes it, how it operates, and how it can be prevented. To this end, neuroscientists have made incredible strides in recent decades in their understanding of the biological mechanisms underlying addiction (see here for a recent example). Along with this new understanding has come a new view of what addiction is. Many neuroscientists now subscribe to the view that addiction is a disease of the brain. According to the “brain disease” model, addicts who start using (for whatever reason) have a very difficult time kicking the habit because use of the abused substance causes chemical changes in the brain. Once these changes occur, the behavior is no longer voluntary but a result of abnormal physiology.

This view of addiction-as brain-disease has successfully found its way into mainstream thought—go to almost any informational website and you will see this framing (replete with evocative language describing how addiction “hijacks” the brain). But what exactly does it mean to say that addiction is a disease of the brain? It certainly might help us develop more effective treatments, as we capitalize on our growing understanding of the precise neural mechanisms at play. But does it also suggest that an addicted criminal defendant should be excused from the legal consequences of her drug-seeking behavior because she couldn’t help herself? Or that an otherwise qualifying recipient should not be denied government entitlements because of substance abuse, since the abuse results from addiction and is therefore not his “fault”? As we can see from these two simple examples, the way we characterize addiction not only has consequences for treatment, but also for the civil, criminal, and administrative legal systems.

Enter an alternative interpretation of what addiction is. This alternative model does not deny that the brain plays an important role in addiction—nor could it, because as every neuroscientist understands, the brain plays an important role in every human behavior. Instead, the model argues for an expanded role for the social and environmental factors that contribute to addictive behaviors.

An example often used to support this more holistic view of addiction is the case of Vietnam veterans. Although many soldiers in Vietnam used heroin extensively during their time in service, most of these men used very occasionally or not at all on their return to the U.S. This contradicts the pure brain disease model—if the veterans were able to quit on their return it means that their brains were not completely “hijacked” by the chemical—and suggests a larger role for environmental factors in ongoing addictive behaviors.

Championed by researchers like Gene Heyman and Bruce K. Alexander for years, this more holistic view of addiction is gaining increased attention as more researchers begin questioning the brain disease model. A recent piece in the Lancet Psychiatry reviews the scientific evidence and argues that support for the brain disease model is not as strong as commonly thought. It goes on to assert that the “brain disease” stance of the National Institute on Drug Abuse has neither prompted more effective treatments nor resulted in meaningful positive policy reform.

Personally, I welcome this debate. Though advances in neuroscience over the past three decades have rightly prompted us to appreciate more fully the role our brains have to play in a range of moods and behaviors (including mood and behavioral disorders), it is now time for us to move beyond the simple truism that “every behavior originates in the brain.” Although this is unquestionably correct, it ignores the myriad other proximate and ultimate causes of behavior rooted in complex interactions of environment, society, evolution, and biology. It also may prompt us to close our eyes to treatment or prevention options that do not involve neural intervention—options that in some cases may be as simple (or as complex) as improving a person’s impoverished environment.