The recent death of Amy Winehouse has once again raised the question of why some people get addicted to alcohol and/or drugs and others don’t. Many people experiment with illicit drugs and even more people drink alcohol on a regular basis, but only a small percentage become addicted. So why do some succumb while others do not?
It’s long been known that genetics and environment play a big role in the risk for addiction. What is less known is that addiction may be a developmental brain disorder. Dr Nora Volkow, director of the National Institute on Drug Abuse, has undertaken brain imaging studies, which show that people who are addicted to cocaine, heroine, and alcohol have fewer dopamine receptors in the brain’s reward pathways than non-addicts. When given a stimulant, study participants with a high number of D2 receptors found the stimulant repugnant while those with low receptor levels (addicts) found it pleasurable. Although needing replication, Volkow’s findings also suggest that abstaining from drugs may increase—and may even normalize in time—the number of D2 brain receptors in addicts.