The effects of transcranial direct current stimulation over the ventromedial prefrontal cortex on reactive aggression in intoxicated and sober individuals

Alcohol-related aggression is a widely observed phenomenon that has detrimental effects on both individuals and society, putatively caused by dysfunction in the prefrontal cortex. The ventromedial prefrontal cortex (vmPFC) plays a critical role in representing the reward value of future actions. Emerging research has suggested that transcranial direct current stimulation (tDCS) over the vmPFC can reduce aggression. However, no study has examined whether tDCS can mitigate intoxicated aggression. In this study, 153 healthy participants consumed alcohol or not and completed the anger-infused Ultimatum Game with simultaneous double-blind anodal tDCS or sham over the bilateral vmPFC. For participants in the anodal tDCS condition, intoxicated participants were less aggressive than sober participants when insulted. However, among sober participants, anodal tDCS increased aggression. For participants in the alcohol condition, we observed no differences in aggression between the anodal tDCS and the sham tDCS conditions. These findings provide mixed support for tDCS as a means to attenuate intoxicated aggression.