Science Says: What makes something truly addictive

Now that the world's leading public health group says too much Minecraft can be an addiction, could overindulging in chocolate, exercise, even sex, be next? The short answer is probably not. The new "gaming disorder" classification from the World Health Organization revives a debate in the medical community about whether behaviors can cause the same kind of addictive illness as drugs. The strictest definition of addiction refers to a disease resulting from changes in brain chemistry caused by compulsive use of drugs or alcohol. The definition includes excessive use that damages health, relationships, jobs and other parts of normal life. Brain research supports that definition, and some imaging studies have suggested that excessive gaming might affect the brain in similar ways. Under a looser definition, addiction is considered "a disease of extreme behavior. Any behavior carried to extreme that consumes you and keeps you from doing what you should be doing becomes an addiction as far as life is concerned," said Dr. Walter Ling, a UCLA psychiatrist. In its widely used manual for diagnosing mental illness, the American Psychiatric Association calls excessive video gaming a "condition" but not a formal diagnosis or disease, and says more research is needed to determine if it qualifies as an addiction.

Drugs and the Brain

Certain drugs including opioids and alcohol can over-activate the brain's reward circuit. That's the system that under normal circumstances is activated when people engage in "behaviors conducive to survival" including eating and drinking water when thirsty, explained Dr. Andrew Saxon, chairman of the association's addiction psychiatry council. The brain chemical dopamine regulates these behaviors, but narcotic drugs can flood the brain with dopamine, encouraging repeated use and making drug use more rewarding that healthy behaviors, Saxon said. Eventually increasing amounts are needed to get the same effect, and brain changes lead to an inability to control use.

What about other substances?

Caffeine is a stimulant and also activates the brain's reward system, but to a much lesser degree than addictive drugs. The "reward" can make people feel more alert, and frequent users can develop mild withdrawal symptoms when they stop, including headaches and tiredness. Caffeine-containing chocolate may produce similar effects. Neither substance causes the kinds of life problems found in drug addiction, although some coffee drinkers develop a tolerance to caffeine and need to drink more to get the same "buzz" or sense of alertness. The World Health Organization recognizes caffeine "dependence" as a disorder; the American Psychiatric Association does not and says more research is needed. "The term 'addiction' is tossed around pretty commonly, like 'chocoholic' or saying you're addicted to reality TV," said IHPI member Dr. Ellen Selkie, a University of Michigan physician who studies teens' use of digital technology. But addiction means an inability to control use "to the point where you're failing at life," she said.