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Research on How Addiction Shapes the Brain Is Still in Its Infancy



Orlando Sentinel
Sunday, May 01, 2016

Orlando, Fla. — He was 40 years old, a father of three and an Orlando house painter, clean and sober for eight years. One night last summer, he climbed into his truck, stuck a needle in his arm and injected himself with what would be his final dose of heroin.

“The paramedics worked on him for a long time ... and when they declared him dead, he was still clutching his last bag of the drug in his fist,” says Pastor Spence Pfleiderer. “That’s the power of addiction.”

As president and CEO of the Orlando nonprofit treatment program Central Care Mission, Pfleiderer has served seven years on the front lines of the war on drugs, fighting for those whose often-fragile grip on sobriety pits them against an unrelenting foe.

“I tell my guys, ‘One of the easiest things in the world is getting you off drugs,’” he says. “It’s staying off that’s the hard part.”

Despite decades of public awareness ads, the nation still has little to show in the battle to overcome addiction. In fact, the American Society of Addiction Medicine reports a “staggering rise” in the problem, particularly with heroin.

The failure, scientists believe, stems from a misguided mentality that addiction is a moral flaw — and that overcoming it is a matter of willpower. The reality, as brain research now shows, is far more complicated.

Addiction is not only a disease, they say, it can apply both to substances such as drugs and alcohol and to behaviors.

“This is why people just can’t quit: Their brains have been changed,” says Dr. Valerie Westhead, a psychiatrist and chief medical officer for Aspire Health Partners in Central Florida. “And we’ve just really fully understood that within the past five years or so, and I don’t think the understanding is pervasive even among medical professionals. It’s going to take a while.”

Through advances in medical scanning, researchers can now trace the brain’s neurotransmitter activity, energy use and blood flow as it is exposed to addictive substances. They can also see how the brain alters itself as it attempts to maintain normalcy despite overwhelming stimulation — which is why addicts need greater and greater quantities to experience the same result.

The research led the American Psychiatric Association to a 2013 landmark decision to classify “gambling disorder” as the first and so far only condition in a category of behavioral addictions that create the same brain responses, rewards, cravings and tolerance levels that addictive drugs do.

Internet gaming disorder could be added next. It’s officially under consideration, while other behaviors and food are being investigated for possible consideration. Dr. Mark Gold, director of research for the Drug Enforcement Administration Educational Foundation and the retired chairman of the University of Florida College of Medicine’s psychiatry department, says sugar demonstrates strong addictive potential. And even something normally considered healthy, such as exercise, can be addictive, he says.

Westhead agrees. “I think there are a lot of unanswered questions about compulsive exercise and eating disorders,” she says. “We’re just beginning to understand the aspects of behavioral addiction.”

While addiction and physical dependence were once used interchangeably, scientists have shown the process of addiction uniquely targets the brain’s so-called “pleasure centers” by flooding them with dopamine, a neurotransmitter. The more powerful the addictive substance, and the more quickly it reaches those dopamine receptors, the more addictive it is.

“The drug becomes more important than anything else,” says Darrell Stevenson, 54, who has spent the past year in an Orlando residential treatment program, staying clean and working. The recovering cocaine addict once easily blew through $400 of the drug in a weekend.

It cost him a marriage, his relationship with his children and five years in prison when, craving his next high, he grabbed a fistful of cash at a bank.

“I went to cash a check, and the teller was taking too long, so I just reached over the counter,” he says. “I had always worked, I had always paid my bills, I always thought of myself as a good guy. But I couldn’t wait. ... I never want to go back to that.”

Stevenson got clean the hard way — behind bars — but researchers say their work may lead to medical solutions instead of criminal justice ones.

“The progress has been so great that you can detox a heroin addict without giving them heroin, morphine or methadone, and you can then give them another medication that makes them immune to opiates,” Gold says. “They can’t even feel it. So they can’t tell the difference between saline and heroin.”

Of course, as Gold points out, they have to take the medication. And that’s the problem. The main drug used for alcohol and opiate abuse, naltrexone, for years came only in pill form, which must be taken at least three times a week and tends to be expensive, Westhead says. A newer, long-acting injectable form may be more reliable, she says, freeing addicts from the constant cravings that make it nearly impossible to think about anything else.

But why does someone become addicted in the first place?

Dr. Yngvild Olsen, an addiction medicine specialist who leads the public policy committee of the American Society of Addiction Medicine, says roughly half of an individual’s vulnerability to addiction stems from genetics — the way our brains are wired when we’re born. The rest is what happens along the way, including, especially, what happens very early in life.