Police officers with the ability to juggle a number of different tasks at once may be less likely to shoot unarmed people, according to research by psychologists at Georgia State University. Police officers taking part in the study took a test of their working memory capacity and were then shown a video of a policeman being shot. During the video their stress levels were measured by monitoring their heart rate and how much they were sweating. The officers were then shown pictures, for a fraction of a second, of people holding a gun or a harmless object like a mobile phone. They were given a choice of pressing either a 'shoot' or don't shoot' button. Among those officers who felt more stress when they watched the video of a policeman getting shot lower levels of working memory capacity - what we use when we try and do a number of things at once - increased the likelihood of shooting unarmed people.
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