Chronic Inhibition of Aggressive Behavior Induces Behavioral Change in Mice

Suppression of anger is more common than its expression among Asian individuals. Emotional suppression is considered an unhealthy emotional regulation. Most studies on emotional suppression have concluded that suppression adversely affects social outcomes, with approximately 5% of the world's population suffering from emotional disorders. However, anger suppression has not received academic attention, and details of the effects of chronic anger suppression on the central nervous system remain unclear. In this study, we performed the resident–intruder test to investigate the effect of chronic suppression of aggressive behavior in mice using a behavioral test battery and to clarify whether suppression of this aggressive behavior is stressful for mice. Mice chronically inhibited aggressive behavior and lost weight. Mice with inhibited aggressive behavior showed a reduced percentage of immobility time during the tail suspension test as well as no changes in activity, anxiety-like behavior, muscle strength, or temperature sensitivity. This study provides scientific evidence for the effects of chronic aggressive behavior inhibition on the body and central nervous system.