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Drugs like opioids and alcohol can over-activate the brain’s reward circuit- the system that under normal circumstances is activated when people engage in “behaviors conducive to survival” including eating food and drinking water, 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, increasing amounts are needed to get the same effect, and the brain changes lead to inability to control use.
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 sense of alertness. The World Health Organization recognizes caffeine “dependence” as a disorder.
The only behavior classified as an addiction in the American Psychiatric Association’s diagnostic manual is compulsive gambling. To be diagnosed, gamblers must have several symptoms including repeatedly gambling increasing amounts of money, lying to hide gambling activity, feeling irritable or restless when trying to stop, and losing jobs or relationships because of gambling.
Research suggests excessive gambling can affect the brain in ways similar to addictive drugs. Some excessive gamblers, gamers and sex “addicts” have other psychiatric conditions, including anxiety, attention deficit disorder and depression, and some mental health specialists believe their compulsive behaviors are merely symptoms of those diseases rather than addictions.
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