Age dependent neural correlates of inhibition and control mechanisms in moderate to heavy drinkers

BACKGROUND: Long-term, heavy alcohol consumption has been associated with impairments in control over alcohol use, but whether this extends to other areas of cognitive and behavioral control such as response inhibition remains unclear. Understanding individual differences in the neural correlates of response inhibition will provide further insight into the neurobiology of heavy drinking. The current study investigated response inhibition in a large sample of moderate to heavy drinkers METHODS: One hundred fifty-three individuals completed a stop signal task while undergoing functional magnetic resonance imaging. Multiple regression analyses focused on blood oxygen level-dependent (BOLD) response contrasts of correct inhibition and failed inhibition as dependent variables and included age, sex, and hazardous drinking (as measured by the Alcohol Use Disorders Identification Test (AUDIT)), and their interactions, as independent variables RESULTS: Age was negatively associated with BOLD response in lateral inferior and middle frontal gyri, anterior cingulate cortex, and inferior parietal lobe for both successful inhibition and failed inhibition contrasts. In addition, there was a significant age × AUDIT interaction in the successful inhibition contrast in the left middle frontal gyrus, with significant negative correlations between AUDIT and BOLD response in older participants, and a significant positive correlation between AUDIT and BOLD response in younger participants CONCLUSIONS: Age appears to be a particularly important factor in predicting BOLD response and may be a critical variable to include in future studies of heavy drinking and alcohol use disorder, particularly those that assess cognitive function. Finally, the age × AUDIT interaction observed in the current study may represent evidence for accelerated aging effects of alcohol on cognitive function.