The brains of nonpartisans are different from those who register to vote with a party

The brains of people with no political allegiance are different from those who strongly support one party, major new research shows.

The largest functional neuroimaging study of its kind to date shows nonpartisan voters process risk-related information differently than partisans.

The findings show nonpartisan voters are a distinct group, not just people reluctant to divulge their political preferences.

Experts found functional brain processing differences between partisans and nonpartisans in parts of the brain which help people to socialize and engage with others—the right medial temporal pole, orbitofrontal/medial prefrontal cortex, and right ventrolateral prefrontal cortex. As people completed a simple risk-related decision-making task there were differences in the blood flow to these regions of the brain between the two groups.

Dr. Darren Schreiber, from the University of Exeter, who led the study, said "There is skepticism about the existence of nonpartisan voters, that they are just people who don't want to state their preferences. But we have shown their brain activity is different, even aside from politics. We think this has important implications for political campaigning—nonpartisans need to be considered a third voter group.

"In the U.S. 40 percent of people are thought to be nonpartisan voters. Previous research shows negative campaigning deters them from voting. This exploratory study suggests US politicians need to treat swing voters differently, and positive campaigning may be important in winning their support. While heated rhetoric may appeal to a party's base, it can drive nonpartisans away from politics all together."

The study, published in the Journal of Elections, Public Opinion, and Parties, was conducted by Dr. Schreiber, Gregory A. Fonzo from the University of Texas, Alan N. Simmons and Taru Flagan from the University of California San Diego, Christopher T. Dawes from New York University, and Martin P. Paulus from the Laureate Institute for Brain Research. The team of political scientists, neuroscientists, and psychiatrists scanned the brains of 110 participants in the U.S. with magnetic resonance imaging (MRI) while they completed the task. Some were registered with one of the two main parties and others were not. The differences in brain activity came when people had to choose whether to make a safe or risky decision, suggesting nonpartisan voters engage differently with nonpolitical tasks.

The experts now hope to carry out more research to discover what the differences in brain activity shows about the personalities and social traits of nonpartisan voters.

During the brain scanning the participants, who lived in San Diego County, had to decide between options which would have provided a guaranteed payoff or those that provided a chance for either losses or gains.

After the experiment the researchers matched participants with publicly available voting records to see if they were registered as Republicans or Democrats, or with no party preference. In total 73 were partisan—56 Democrats and 17 Republicans—and 37 were nonpartisan.

The right medial temporal pole, orbitofrontal/medial prefrontal cortex, and right ventrolateral prefrontal cortex have been shown to be important for human social connections in hundreds of brain imaging studies. They help people to connect to their social groups, understand the thoughts of others, and regulate the reactions we have to others.