Effects of alcohol and trait anger on physical aggression in men

According to recent theoretical models, the alcohol-aggression link is predicated on the interaction among many variables, including the drinker's personality. The few studies that investigated effects of personal dispositions on alcohol-related aggression have been inconclusive, possibly because the role of dispositions related to affect were largely ignored. As such, the purpose of this study was to investigate the interactive effect of alcohol and trait anger on physical aggression.

Participants were 136 male social drinkers who reported high, moderate, and low levels of trait anger and were nonrandomly assigned to an "alcohol" or "no-alcohol" control beverage group. Participants competed in an aggression paradigm in which electric shocks were received from and administered at will to a fictitious opponent during a competitive task. Shock intensity, duration, and proportion of highest shock served as indexes of aggression.

Intoxicated participants with moderate trait anger selected higher shock intensity and had a greater proportion of highest shock, compared with their sober counterparts. Within the alcohol group, high- and moderate-anger participants were more aggressive than low-anger participants. Intoxicated participants selected longer shock durations following both low and high provocation, and they evinced a greater increase in shock duration from low to high provocation than their sober counterparts. Independent of beverage group, men who reported a high or moderate level of trait anger displayed more aggression on all measures, compared with those who reported low anger disposition.

The present findings suggest that individuals who report low levels of trait anger may be more resistant to the potentiating effects of alcohol on aggression and that the effects of alcohol on aggression may be most pronounced in men who have a moderate level of trait anger. Furthermore, independent of intoxication, trait anger appears to be a risk factor for physical aggression in men.