New research from The University of Texas at Austin and the University of Minnesota has found that bottling up emotions can make people more aggressive.
The study could have important implications for reducing violence and helping people in professions such as law enforcement and the military better cope with long hours and stressful situations.
The psychologists used a pair of classic movie scenes in their research. They found that subjects who were asked to suppress their emotions and show no reaction to a notoriously disgusting scene in the 1983 film "The Meaning of Life" and another in the 1996 film "Trainspotting" were more aggressive afterwards than subjects who were allowed to show their revulsion.
The research reinforces scientists' understanding of the "ego depletion effect," which suggests people who must keep their emotions bottled up - not reacting to a difficult boss at work, for example - are more likely to act aggressively afterwards - by yelling at their children, perhaps.
Subjects in the experiment who were deprived of sleep before watching the scenes reacted no differently than those who were well rested. This suggests that fatigue does not make people more aggressive, as some previous studies have suggested.
"Our research suggests people may become more aggressive after they have to control themselves," says co-author Arthur Markman, a psychology professor at The University of Texas at Austin "Whatever psychological mechanisms are at work when people deal with stress and then have to exercise self control later are not the same thing that happens when you're tired."
The study has been published in the journal Social Psychological and Personality Science.