blog.bioethics.net

Addiction through the lens of neuroscience

Newsweek's cover article this week looks at how neuroscience is prompting researchers to develop new medications and vaccines to treat addiction:

The emerging paradigm views addiction as a chronic, relapsing brain disorder to be managed with all the tools at medicine's disposal. The addict's brain is malfunctioning, as surely as the pancreas in someone with diabetes. In both cases, "lifestyle choices" may be contributing factors, but no one regards that as a reason to withhold insulin from a diabetic. "We are making unprecedented advances in understanding the biology of addiction," says David Rosenblum, a public-health professor and addiction expert at Boston University. "And that is finally starting to push the thinking from 'moral failing' to 'legitimate illness'."

In laboratories run and funded by the National Institute on Drug Abuse (NIDA), fMRI and PET scans are forcing that infuriating organ, the addicted brain, to yield up its secrets. Geneticists have found the first few (of what is likely to be many) gene variants that predispose people to addiction, helping explain why only about one person in 10 who tries an addictive drug actually becomes hooked on it. Neuroscientists are mapping the intricate network of triggers and feedback loops that are set in motion by the taste—or, for that matter, the sight or thought—of a beer or a cigarette; they have learned to identify the signal that an alcoholic is about to pour a drink even before he's aware of it himself, and trace the impulse back to its origins in the primitive midbrain. And they are learning to interrupt and control these processes at numerous points along the way. Among more than 200 compounds being developed or tested by NIDA are ones that block the intoxicating effects of drugs, including vaccines that train the body's own immune system to bar them from the brain. Other compounds have the amazing ability to intervene in the cortex in the last milliseconds before the impulse to reach for a glass translates into action. To the extent that "willpower" is a meaningful concept at all, the era of willpower-in-a-pill may be just over the horizon. "The future is clear," says Nora Volkow, the director of NIDA. "In 10 years we will be treating addiction as a disease, and that means with medicine."

As you would expect, the research on a cocaine vaccine comes up:

The cocaine vaccine, developed by Thomas Kosten of Baylor College of Medicine, could be on the market as early as 2010. It would have to be given three or four times a year, but presumably not for life, says Kosten. While the vaccine is being studied in people who are already addicted to cocaine, it could eventually be used on others. "You could vaccinate high-risk teens until they matured to an age of better decision-making," Kosten says. He acknowledges the obvious civil-liberties issues this raises. "Lawyers certainly want to argue with us on the ethics of it," he says, "but parent groups and pediatricians have been receptive to the idea."

So, who makes the decisions about which teens are "high risk"? And would the teens have a say in whether they get the anti-cocaine jab? What about for the still-in-development nicotine vaccine?

There's plenty to think about in this article, including a bit in the middle about research into using pharmaceuticals to restore an addict's "free will."

-Greg Dahlmann