When considering the added value of assessing AO and delay, these constructs may be particularly informative to neurodevelopmental research documenting the negative effects of alcohol on structural and functional brain development during emerging adulthood. Neuroimaging research has found that binge drinking during adolescence leads to impairments in memory, academic performance, attention, decision making, and reasoning (e.g., Alfonso-Loeches and Guerri, 2011; Crego et al., 2009; Squeglia et al., 2011). The independent effects of AO and delay in the current study are consistent with the notion that adolescent drinking exerts incrementally negative effects on brain development with increasing levels of consumption. Of note, we did not find interactions between AO and delay in the prediction of heavy drinking or problems during senior year of college. This result argues against a “critical period” of vulnerability to the neurotoxic effects of alcohol limited to early adolescence, suggesting instead that vulnerability may persist throughout emerging adulthood. Assessing AO and delay in future neuroimaging studies may help to parse out what negative effects are linked to an early AO versus a quick progression to heavy drinking.
