Acute Effects of Alcohol on Behavioral Control and Simulated Driving in Frequent and Infrequent Binge Drinkers

Frequent binge drinking is associated with high rates of impaired driving and myriad alcoholrelated accidents. One potential explanation for the correlation between frequent binge drinking and elevated alcohol-related injury risk is that frequent binge drinkers are generally more impulsive, and subsequently more disinhibited by alcohol compared to infrequent binge drinkers. This research proposal will explore this hypothesis and its relevance to impaired driving by examining acute alcohol effects on inhibitory and activational mechanisms of behavioral control, and their relation to simulated driving performance in frequent and infrequent binge drinkers. In Experiment 1, frequent and infrequent binge drinkers will be compared on neurocognitive measures and simulated driving under alcohol and placebo. It is hypothesized that frequent binge drinkers will be more disinhibited by alcohol compared to infrequent binge drinkers. The degree to which the acute impairing effects of alcohol on basic neurocognitive mechanisms contribute to impaired simulated driving also will be examined. Experiment 2 addresses the role of acute tolerance (recovery) as a contributor to alcohol-related injuries. Recent evidence has indicated that acute recovery to the subjective intoxicating effects of alcohol is greater in frequent binge drinkers compared to their lighter drinking counterparts. However, other evidence indicates that acute recovery does not occur for alcohol-induced impairment of inhibitory mechanisms of behavioral control. Thus, the second experiment will examine the dissociation in acute recovery of subjective intoxication and behavioral control in frequent and infrequent binge drinkers. It is predicted that greater recovery in subjective intoxication, yet no recovery in inhibitory control and driving, in frequent binge drinkers may account for the greater accident risk in this demographic group.