Experts often blame substance abuse by teens and young adults on peer pressure and the stresses of moving from youth to adulthood. A new study, however, argues that young people's vulnerability to drug abuse stems in large part from biological rather than sociological factors.
R. Andrew Chambers and colleagues note that teens and young adults experiment with and become addicted to drugs and alcohol far more often than older adults, and that adult substance abuse generally begins in the teen or early adult years. In addition, they point out, early onset of substance abuse predicts greater severity. The researchers say scientific evidence shows that sociocultural factors cannot fully account for these patterns, which are seen across cultures and are true for both males and females.
The researchers believe that this enhanced vulnerability of adolescents and young adults to substance abuse stems from developmental changes in the brain circuitry underlying motivation, impulsivity, and addictive behavior. Reviewing more than 140 studies on adolescent brain development and related research, the researchers conclude that "particular sets of brain circuits involved in the development of addictions are the same ones that are rapidly undergoing change during adolescence. Normally, these processes cause adolescents to be more driven than children or adults to have new experiences. But these conditions also reflect a less mature neurological system of inhibition, which leads to impulsive actions and risky behaviors, including experimentation and abuse of addictive drugs."
Developmental changes that can increase vulnerability to substance abuse, the researchers say, include:
"Developmental neurocircuitry of motivation in adolescence: a critical period of addiction vulnerability," R. Andrew Chambers, Jane R. Taylor, and Marc N. Potenza, American Journal of Psychiatry, Vol. 160, No. 6, June 2003, 1041-52. Address: R. Andrew Chambers, Connecticut Mental Health Center, 34 Park Street Third Floor, New Haven, CT 06508, robert.chambers@yale.edu.
"Adolescents are neurologically more vulnerable to addictions," press release, Yale University, June 18, 2003.