Linking Sleep and Aggression: Examining the Role of Response Inhibition and Emotional Processing

Although sleep loss is theorized to increase aggression risk, knowledge regarding the sleep-aggression relationship, or explanatory psychological processes, is limited. This study examined whether recent sleep duration predicted subsequent laboratory aggression, and whether neurocognitive indices of attentional and motor inhibition and negative emotional processing explained the sleep-aggression relationship. Participants (n=141) wore Fitbit Flex devices and kept a sleep diary for three days. Event-related potentials were measured during an Emotional-Linguistic Go/No-Go task, followed by a laboratory aggression paradigm. Results of mixed-model repeated measures ANOVAs linked shorter sleep duration with reduced motor inhibition processing during negative and neutral word blocks, and greater aggression. However, neurocognitive indices did not explain the sleep-aggression link. This is the first evidence that naturally occurring sleep loss predicts increases in laboratory aggression across the task and suggests that shorter sleepers are more vulnerable to rash action in negative and neutral contexts. Implications of these findings for understanding aggression will be discussed.