Many people believe that addiction to alcohol and other drugs is a weakness or lack of willpower that is primarily a moral or character problem. Contrary to this popular opinion, scientific research, especially in the last 10 years, has convinced experts that addiction is definitely a disease of the brain.
There is a major difference between addiction and simple use or abuse. People who use drugs or drink alcohol too much can still exert control over their behavior. However, once they become addicted, their brains change in such a way that they cannot live without drugs or alcohol. At this point, they have lost the ability to say “No.”
Control is lost because the brain has changed in complex ways. Addictive drugs such as alcohol, nicotine, and cocaine can affect the structure and function of the brain. Just like in an electrical system, drugs can change the circuits in the brain that control emotions and motivation, impairing an addicted person’s power of choice. With repeated heavy use, the structure and shape of brain cells and the connections between them change radically. The brains of addicts are very different than those of non-addicts.
Of course, this doesn’t happen overnight. People begin using alcohol, nicotine or other drugs because these substances make them feel good. These drugs cause an increase in certain neurotransmitters (chemicals that communicate information between brain cells) that, in turn, produce feelings of euphoria and pleasure. Over time, with continued use, addictive drugs cause long-lasting changes in the brain’s pleasure and reward system. Chronic use of a drug to stimulate these neurotransmitters reduces the brain’s natural ability to produce pleasure without the drug. Then, when a person stops using drugs, he no longer can experience pleasure and may feel depressed and anxious. After a while, alcohol and drugs are needed just to feel “normal”.
Why doesn’t everyone who drinks, smokes or uses drugs become addicted? Vulnerability to addiction is affected by many factors. Genetic predisposition appears to be a major predisposing factor particularly with alcohol dependence. Children of alcoholics are 2 to 4 times more likely to become alcoholics or drug addicts and more than 60% of alcoholics have family histories of alcoholism. Genetics may especially play a role in early-onset alcoholism.