Bottling up emotions can make you more aggressive

The study, by the universities of Texas and Minnesota, can have an important bearing on reducing violence and helping law enforcers and soldiers cope with long hours and stressful situations.

The psychologists found that subjects who were asked to suppress their emotions and show no reaction to notoriously disgusting scenes in the movies "The Meaning of Life" and "Trainspotting", were more aggressive afterwards than subjects who were allowed to show their revulsion.

The research suggests people who 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, according to a Texas statement.

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, psychology professor at Texas.

"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," said Markman.

Subjects in the study included US Army soldiers, cadets at the US Military Academy at West Point and college students.