The way a person’s brain responds to a single disgusting image is enough to reliably predict whether he or she identifies politically as liberal or conservative. As we approach Election Day, the researchers say that the findings reported in the Cell Press journal Current Biology on October 30 come as a reminder of something we all know but probably don’t always do: “Think, don’t just react.”
P. Read Montague of Virginia Tech says he was initially inspired by evidence showing that an individual’s political affiliation is almost as heritable as height. Montague and his colleagues also recognized that those political ideologies summarize many aspects of life—attitudes associated with sex, family, education, and personal autonomy, for instance—and have deep connections to the way our bodies respond to threats of contamination or violence.
To find out just how fundamental those connections are, Montague and his colleagues asked whether functional magnetic resonance images (fMRI) of the brain taken as people passively looked at a series of disgusting, pleasant, and neutral images was enough to give away their political leanings, as measured on a standardized test. (The Wilson Patterson inventory produces a score from 0 to 1, from extremely liberal to extremely conservative.)