Neuropsychological correlates of risky alcohol use by young adults

Traits of impulsivity, reward sensitivity and disinhibition have been linked to risky alcohol use in young adults, suggesting that inherent deficiencies in frontal lobe function increase alcohol-related risk. A community sample of young adult social drinkers (n = 47) was divided into low risk, hazardous, and harmful drinkers based on the Alcohol Use Disorders Identification Test (AUDIT) scores. MANCOVA controlling for age and gender revealed a significant effect of the AUDIT group on three well-known neuropsychological tests of frontal lobe functioning: the Wisconsin Card Sorting Test (WCST), the Iowa Gambling Task (IGT) and the Tower Test, F(8, 32) = 2.72, p = .02, observed power = .86. Individual effects were significant for IGT, F(2, 18) = 4.21, p = .03, and for the Tower Test, F(2, 18) = 5.15, p = .02. WCST perseverative errors approached significance (p < .10). These neuropsychological tests can distinguish patients with focal lesions of the frontal lobes from those with lesions of posterior regions as well as from controls, thus our results in a non-clinical sample are striking. As participants were social drinkers who reported never being treated for any alcohol or drug related problem, with no history of head injury or neuropsychological or psychological disorder, findings are consistent with our hypothesis that some of the executive function deficits reported in alcoholic samples may reflect premorbid traits rather than sequelae of chronic alcoholism. Such premorbid deficits are likely to predispose to risky alcohol use via mediating traits such as impulsiveness, disinhibition and reward sensitivity.