Addiction is a chronic brain disorder and not simply a behavior problem involving alcohol, drugs, gambling or sex, experts contend in a new definition of addiction, one that is not solely related to problematic substance abuse.

The American Society of Addiction Medicine (ASAM) just released this new definition of addiction after a four-year process involving more than 80 experts.

"At its core, addiction isn't just a social problem or a moral problem or a criminal problem. It's a brain problem whose behaviors manifest in all these other areas," said Dr. Michael Miller, past president of ASAM who oversaw the development of the new definition. "Many behaviors driven by addiction are real problems and sometimes criminal acts. But the disease is about brains, not drugs. It's about underlying neurology, not outward actions."

The new definition also describes addiction as a primary disease, meaning that it's not the result of other causes, such as emotional or psychiatric problems. And like cardiovascular disease and diabetes, addiction is recognized as a chronic disease; so it must be treated, managed and monitored over a person's lifetime, the researchers say.

Two decades of advancements in neuroscience convinced ASAM officials that addiction should be redefined by what's going on in the brain. For instance, research has shown that addiction affects the brain's reward circuitry, such that memories of previous experiences with food, sex, alcohol and other drugs trigger cravings and more addictive behaviors. Brain circuitry that governs impulse control and judgment is also altered in the brains of addicts, resulting in the nonsensical pursuit of "rewards," such as alcohol and other drugs.

A long-standing debate has roiled over whether addicts have a choice over their behaviors, said Dr. Raju Hajela, former president of the Canadian Society of Addiction Medicine and chair of the ASAM committee on addiction's new definition.

"The disease creates distortions in thinking, feelings and perceptions, which drive people to behave in ways that are not understandable to others around them," Hajela said in a statement. "Simply put, addiction is not a choice".

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