How did you become interested in drug addiction research?
The first time I was confronted by the face of mental illness on the street was after I left the rural, small town in Texas I grew up in and moved to Baltimore, to attend Johns Hopkins University. I decided to increasingly focus my studies on behavioral processes that relate to mental illness because I really was profoundly affected by seeing people struggling with their addictions and their mental disorders.
At some point, an addict decides, ‘I’ve got to stop using drugs. It’s killing me. It’s ruining my life.’ At that point they are motivated to quit, and yet they are unable to stop. This is mind-blowing to me. We assume we have control over our own behaviors. Yet these people have somehow become trapped. The question is why?
How do you study drug addiction?
About 15 years ago, I started looking into how the normal brain resists reward using rats and vervet monkeys. We’re all attracted to rewards — be they flavorful foods or the latest technology on the shelf — but we resist some of them because they aren’t good for us, or there’s a long-term cost associated with them. We now know there are circuits in the brain that help us resist reward. We think these “resist” circuits may be linchpins for addictions. If we could turn these circuits back on in people who are addicted to drugs, we might be able to translate their motivation to quit into effective abstinence.
What most excites you about this area of research?
It is very exciting to be on the cusp of addressing what I would consider being an enormous unmet need. If you are addicted to cocaine or methamphetamine, there are zero medications that are currently approved in the United States to treat you. Advances in brain imaging and genetics give us the opportunity to make headway toward this unmet need moreso than ever before.
Why do you need to study animals in order to understand drug addiction in humans?
The methodologies that are available for understanding the brain in the living human are limited. There’s only so much a brain scanner can tell us. There’s only so much genetics can tell us. If we’re going to make any progress toward tying biological understanding from human subjects into treatments, we need the intermediate animal studies that help us understand what’s a cause, what’s an effect, which processes relate to behavioral outcomes and which ones don’t. This is the crucial piece of the puzzle animal studies provide to addiction research.
Animal rights activists have attacked and threatened you because some of your research involves the use of non-human primates. What motivates you to continue your research?
As a neuroscientist, non-human primates will always be an important part of our research because there’s no escaping the fact that when it comes to the brain, the rodent models have their limitations. I believe we have the opportunity to improve people’s quality of life dramatically. If we can make 50 percent of all addicts’ lives 50 percent better, that’s an immeasurable impact. So I feel comfortable with the ethical principles that support my work.
But, I have a different question: What about the ethics of inaction? I would like the people who question the ethics of research to explain why it’s ethically justifiable to withhold research that would crucially advance the human condition. How do you explain to people whose suffering could potentially be alleviated by such research that they are not worthy of it? When I think about the ethics of inaction, then I have to continue. I think the cost of doing nothing when you can do something is unacceptable.
What do you think is the most common misperception people have about animals in research?
You’ll often hear the concept that computer models or cell-based models that don’t involve living animals can give us all the information that living systems can, and that is simply incorrect. Today, in order to understand something as complex as the brain, we need to study the living brain, either in humans or in animals directly. The brain still amounts to the most complex machine in the world. We cannot model something we don’t understand.
There will be alternatives for all animal research someday, but not today.