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Background Low levels of alcohol responses (low LRs) are genetically influenced phenotypes that are identified before alcohol dependence and predict future heavy drinking and alcohol problems. A recent paper described 13 LR-related blood oxygen level-dependent ( BOLD) response contrast patterns observed during an emotional face recognition task that might reflect cognitive processes contributing to LR and that might themselves predict adverse alcohol outcomes ( Paulus et al., Biol Psychiatry 2012; 72: 848). This paper evaluates the predictive implications of those functional magnetic resonance imaging (f MRI) patterns. Methods Of 120 subjects from Paulus and colleagues (2012), 114 (57 low and high LRs; ~50% females) were interviewed 5 years later at age 25. Correlations between baseline f MRI patterns and alcohol-related outcomes were evaluated, and regression analyses were used to determine if BOLD response contrasts incremented over LR in predicting outcomes. Results Baseline f MRI patterns in 5 of 13 baseline regions of interest correlated with adverse outcomes. Such patterns in insular regions, particularly the left anterior insula, and the right frontal gyrus, added to LR in predicting alcohol problems. The relationships remained robust when exact binomial procedures were used, but, reflecting the small sample size, it was not possible to adequately consider Bonferroni corrections. Conclusions The data suggest that f MRI BOLD response contrasts predicted heavier drinking and alcohol problems 5 years later, even after considering baseline low LRs. Future work will focus on whether f MRI results can predict outcomes in larger samples and among young nondrinkers, as well as how the imaging results increase understanding of the processes through which LR operates. [ABSTRACT FROM AUTHOR]

Background: The low level of response (LR) or sensitivity to alcohol is genetically influenced and predicts heavy drinking and alcohol problems. Functional magnetic resonance imaging (fMRI) studies using cognitive tasks suggest that subjects with a low-LR process cognitive information differently after placebo and alcohol than those with a high LR, but no studies have evaluated whether similar LR group differences are seen during an emotional processing task. Methods: The fMRI data were gathered from 116 nonalcoholic subjects (60 women) after oral placebo or approximately .7 mL/kg of ethanol while performing a modified emotional faces processing task. These included 58 low- and high-LR pairs matched on demography and aspects of substance use. Results: Blood alcohol levels and task performance were similar across LR groups, but low-LR subjects consumed approximately .8 drinks more/occasion. Thirteen brain regions (mostly the middle and inferior frontal gyri, cingulate, and insula) showed significant LR group or LR × placebo/alcohol condition interactions for emotional (mostly happy) faces relative to non-face trials. Low-LR subjects generally showed decreasing blood-oxygen level-dependent response contrasts across placebo to alcohol, whereas high LR showed increasing contrasts from placebo to alcohol, even after controlling for drinking quantities and alcohol-related changes in cerebral blood flow. Conclusions: Thus, LR group fMRI differences are as prominent during an emotional face task as during cognitive paradigms. Low-LR individuals processed both types of information in a manner that might contribute to an impaired ability to recognize modest levels of alcohol intoxication in a range of life situations. [ABSTRACT FROM AUTHOR]