Trait modulation of alcohol-induced laboratory aggression.

Modest alcohol and aggressive trait effects on laboratory-induced aggression among men have been reported with some consistency in the literature. Relationships between aggressive personality traits and laboratory-induced aggression appear to become less consistent under the influence of alcohol. Several research teams have found suggestions that the effects of alcohol on laboratory aggression may be reduced or even reversed among individuals with aggressive personality traits. This study examined the effects of alcohol on the aggressive responding on the Point Subtraction Aggression Paradigm (PSAP) of eight undergraduate men who generated evidence on the Million Clinical Multiaxial Inventory-II (MCMI-II) of sadistic-aggressive personality disorder features. This sample was compared with a group of 18 undergraduate male peers without MCMI-II elevations described in a previous study. Neither alcohol ingestion (0.8 ml/kg) nor aggressive personality traits predicted laboratory behavior in isolation, but alcohol was found to selectively attenuate (d = 0.75) PSAP responding for the sadistic-aggressive as opposed to the control subjects (i.e., a significant aggressive trait by alcohol interaction). The possible value of this counterintuitive response tendency in identifying men at elevated risk for alcohol-related aggression was discussed. Large, immediate reductions in laboratory-based aggressive responding while under the influence of alcohol might provide a paradoxical high risk indicator that has not been previously identified.