who initiated drinking at ages 15-17. However, a recent brain imaging study reported a reduced volume of prefrontal white matter in association with AUD among 15-to-17-year-old girls but not boys (Medina et al., 2008), a finding that did support the gender-specific association found in this study. A better understanding of any possible neurotoxic effects of adolescent drinking clearly requires much additional research, including studies with samples large enough to reliably test for gender differences. Any direct pharmacological effect specific to early alcohol use also appears unlikely, because similar risks associated with early use have been reported for tobacco and cannabis (Kandel et al., 2007; Lynskey et al., 2006) and because early initiation of drinking was shown to increase the odds of drug rather than alcohol dependence in one prospective study (King and Chassin, 2007).
