Prolonged exertion of self-control causes increased sleep-like frontal brain activity and changes in aggressivity and punishment

Impulsive reactions in social interactions may result in poor outcomes. Cognitive states like mental fatigue from extended practice with demanding tasks—especially under sleep restriction—appear to impair self-control and foster impulsive behaviors, including aggression. This study demonstrates that exerting self-control for ~45 minutes increases the propensity to engage in aggressive acts in socially relevant choices, as measured via economic games. These behavioral changes are associated with increased sleep-like (delta) EEG activity within frontal areas implicated in decision-making and impulse control. Local sleep-like slow waves may disengage frontal regions, reducing effective self-control. Results suggest sleep-like activity can emerge in the awake brain on relatively short timescales and measurably impact socially relevant behavior.