Political polarization study finds liberal and conservative brains have one thing in common

PROVIDENCE, R.I. — There seems to be no end in sight to the political divide splitting America in two right now. While political polarization is not a new phenomenon, researchers say they still know very little about what causes people to see the world through an ideological bias. Now, a team from Brown University reveals liberals and conservatives actually do share some common ground — they all hate uncertainty.

Their study finds the brains of “political partisans” on both sides of the spectrum show an inability to tolerate uncertainty. These individuals also have a need to hold onto predictable beliefs about the world they live in.

Examining a group of liberals and conservatives, researchers discovered watching politically inflammatory debates or news coverage exacerbates each person’s intolerance of the unknown. Liberals began to display more liberal thinking and conservatives moved further to the conservative side. Despite their ideological differences, the team finds the same brain mechanics are driving this behavior.

“This is the first research we know of that has linked intolerance to uncertainty to political polarization on both sides of the aisle,” says study co-author Oriel FeldmanHall, an assistant professor of cognitive, linguistic and psychological sciences at Brown, in a university release. “So whether a person in 2016 was a strongly committed Trump supporter or a strongly committed Clinton supporter, it doesn’t matter. What matters is that an aversion to uncertainty only exacerbates how similarly two conservative brains or two liberal brains respond when consuming political content.”

Political views not to blame for polarized society?

Study authors used fMRI scans to measure brain activity while participants watched three different programs. The 22 conservatives and 22 liberals viewed a neutrally-worded news report on the very polarizing topic of abortion, a fiery political debate segment, and a completely non-political nature show.

After seeing the videos, participants answered questions gauging their understanding and opinions of the different segments. They also completed political and cognitive surveys measuring their intolerance of uncertainty. According to study co-author Jeroen van Baar, the results show political polarization is less about what people think and more about how their brains cope with the world around them.

“We found that polarized perception — ideologically warped perceptions of the same reality — was strongest in people with the lowest tolerance for uncertainty in general,” says van Baar, a former Brown researcher now at Trimbos, the Netherlands Institute of Mental Health and Addiction. “This shows that some of the animosity and misunderstanding we see in society is not due to irreconcilable differences in political beliefs, but instead depends on surprising — and potentially solvable — factors such as the uncertainty people experience in daily life.”

“We used relatively new methods to look at whether a trait like intolerance of uncertainty exacerbates polarization, and to examine if individual differences in patterns of brain activity synchronize to other individuals that hold like-minded beliefs,” FeldmanHall adds.

Birds of a (political) feather flock together

The study also reveals brain activity and neural responses in partisans diverge between liberals and conservatives. Researchers say these differences reflect each side’s subjective interpretation of the content they’re viewing. People who strongly identify as liberals processed political videos in a very similar way to other liberals in the study; a trait called neural synchrony. Study authors discovered the same thing when examining the brains of conservatives.

“If you are a politically polarized person, your brain syncs up with like-minded individuals in your party to perceive political information in the same way,” FeldmanHall explains.

The results also show people displaying a higher level of intolerance for uncertainty are more sensitive to politically polarizing content. Surprisingly, the news report on abortion with a completely neutral tone did not exacerbate the group’s polarized perceptions.

“This suggests that aversion to uncertainty governs how the brain processes political information to form black-and-white interpretations of inflammatory political content,” the researchers explain.

“This is key because it implies that ‘liberal and conservative brains’ are not just different in some stable way, like brain structure or basic functioning, as other researchers have claimed, but instead that ideological differences in brain processes arise from exposure to very particular polarizing material,” van Baar concludes. “This suggests that political partisans may be able to see eye to eye — provided we find the right way to communicate.”

The study appears in the journal PNAS.

Leave a Reply

Your email address will not be published. Required fields are marked *