"The teen brain is a work in progress, making it more vulnerable than the mature brain to the physical effects of drugs. The potential for developing substance abuse and dependence is substantially greater when an individual’s first exposure to alcohol, nicotine and illicit drugs occurs during adolescence than in adulthood."

Source

Steinberg, L., Distinguished University Professor and Laura H. Carnell Professor of Psychology, Department of Psychology, Temple University and author of "You and Your Adolescent: The Essential guide for ages 10 to 25" (personal communication, June 9, 2011), as quoted in "Adolescent Substance Use: America’s #1 Public Health Problem," The National Center on Addiction and Substance Abuse at Columbia University (New York, NY: National Center on Addiction and Substance Abuse at Columbia University, June 2011), p. 13.
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