Cardenas et al. (2013). This study sought to isolate the influence of alcohol consumption on WM microstructure in the absence of co-occurring substance use or behavioural disorders. To this end, the authors included AU youth (defined as youth with AUDs; N = 50, ages 14–19) as well as age- and gender-matched non-AU youth (controls; N = 50). Compared with non-AU youth, AU youth did not show a pattern of overall lower FA, decreased FA in WM tracts of the limbic system, or higher MD. Rather, AU youth showed increased FA within WM limbic tracts (e.g., forinix, stria terminalis), but increased FA was not associated with any AU measures. The authors highlighted the different developmental pattern of FA (increased rather than decreased) in this sample of AU youth. Because greater FA in limbic regions was not associated with AU measures the authors posited that these differences may represent a precursor or biomarker of later AU. As the WM tracts with greater FA in this study connect with the septal nuclei, which are involved in reward/reinforcement, the authors suggest that drinking behaviour may be reinforced in youth who have higher FA, and potentially greater myelination in these regions.
