political attention

There was a fascinating study just published by a team from the University of Nebraska.  What they did was flash pictures of politically charged individuals (e.g. Bill Clinton, George Bush) on both sides of the aisle to people with strong political orientations.  Then they measured both galvanic skin response (physiological arousal) and visual attention. 

What they found is really interesting.  The liberal subjects had a stronger physiological response and longer visual attention for the pictures of people they liked (e.g. Clinton).  On the other hand, conservatives had stronger physiological response and longer visual attention for people they don’t like (e.g. Clinton again).  They used a variety of people in the images, so it wasn’t Clinton himself that caused the reaction.

They promote a hypothesis for why this happened that I would like your opinion on.  I am not sure if I buy it, although it sounds reasonable.  The conservative mentality is about protecting us from out-group threats (anti-immigration, strong military) and in-group threats (people with non-traditional values or behaviors).  So their attention is naturally fixated on things they don’t like.  On the other hand, the liberal mentality is about improving the world for out-groups (foreign aid) and in-groups (minority rights).

What do you think?  The actual physical responses are statistically significant, but they are really speculating about the explanation.  Could it be?