Science-- there's something for everyone

Friday, April 13, 2012

Holding something makes people think other people are holding it too


There’s an old saying that if you’re a hammer, every problem is a nail.  In other words, our perceptions and abilities color how we view the world around us.  In a rather chilling validation of this aphorism, Jessica Witt of Purdue University and James Brockmole of the University of Notre Dame have found that wielding a gun makes people think other people are doing likewise.

To test this, the researchers showed 34 student volunteers a variety of scenes, some of which included a person holding a gun (though not aimed at the screen) and some of which included someone holding a neutral object. The volunteers held either a WII gun or a foam ball and were instructed to raise the object if they thought the person in the image held a gun and lower it if the person did not hold a gun (these directions were reversed in other trials). The students were more likely to think they saw a gun even when one was not present if they themselves were holding a gun.

In a second experiment, 38 volunteers viewed images of people wearing ski masks and brandishing either a gun or a shoe directly at the camera. This time, each volunteer went through all the images while holding the gun and repeated the exercise holding the foam ball (or vice versa). Again, people were biased to see a gun while holding a gun themselves.

In another experiment, 40 student volunteers were run through the same images as in the first experiment, all while holding the foam ball.  This time, a real but non-functional pistol was placed next to the computer monitor of half the participants. To be clear, at no point did the subjects handle the guns. Having the gun in full view did not bias participants to see more guns in the images.

These data suggest that it’s the physical handling of the gun that makes people more likely to think other people have guns as well. But does this apply to objects other than guns?  I’m glad you asked.  In the final experiment, 44 volunteers were shown the shoe vs. gun images from experiment two, but this time they were holding either a ball or a shoe.  Surprisingly, holding a shoe made people more likely to see a shoe! It turns out that there’s nothing special about guns that elicits this reaction.  We just have a tendency to think other people are carrying whatever we’re carrying.  Most of the time, this inclination is benign, but it can have tragic consequences when firearms are involved.