Understanding Addiction as a Brain Disease

Addiction is more than frequent drug use. Recent scientific research provides strong evidence that drugs not only interfere with normal brain functioning but also have long-term effects on brain metabolism and activity. Those addicted to drugs experience compulsive drug craving and cannot quit by themselves. Treatment is necessary to end this compulsive behavior.

Repeated use of a drug results in chemical and molecular alterations in the brain, and such changes have become equated with drug dependence. Although a person can initially be introduced into using drugs because of genetic, psychological, and socio cultural factors, once a drug is taken, the drug-taking behavior itself may promote continued drug-seeking behavior via the changes caused in the brain.

Continuous drug use leads to a cascade of intracellular events that changes the excitability of cells and ultimately alters neuronal circuit activity. These alterations are believed to elicit changes that provoke acute positive reinforcing effects because of drug interactions with individual transmitter systems within the general reward circuitry of the brain (i.e., the limbic system). Long-term drug effects include tolerance, sensitization, dependence, and withdrawal. Because these changes in reward circuitry are neuro adaptations, drug addiction may be defined as a brain disease.

It is as if there is a switch in the brain that turns on at some point during a person’s drug-taking behavior. This switch flips on at different points for different drugs and different individuals, but once it is on, it fundamentally changes the user from a drug user/ abuser to a drug addict.