PROVIDENCE, R.I. [Brown University] — When people with extreme political views see politically charged content, their brains process the information in the same way — even when their views are at the opposite end of the ideological spectrum.
That’s according to a new study led by psychological and cognitive researchers and published in the Journal of Personality and Social Psychology. The research provides psychological evidence for the theory of horseshoe politics, which holds that the views of people at the far left and far right of the political spectrum resemble each other more closely than they do people with moderate views.
“Our study showed that the brains of highly conservative and highly liberal individuals are processing the same charged political content in ways that are even more similar than people in their own political parties with more moderate beliefs,” said study author Oriel FeldmanHall, a professor of cognitive and psychological sciences at Brown University affiliated with the University’s Carney Institute for Brain Science.
A total of 44 people — half on the right side of the political spectrum and half on the left — participated in experiments led by Daantje de Bruin, a Ph.D. student in FeldmanHall’s lab. The participants represented a range of ideologically extreme attitudes, with most being on the more extreme end. All were shown a video while they were inside an MRI scanner so the researchers could collect and analyze brain images and data on electrical activity on the skin based on their response.
The team found that participants with more extreme views showed heightened neural activity to politically charged content in brain regions implicated in emotional processing, including the amygdala, periaqueductal grey and posterior superior temporal sulcus. Those who shared an extreme perspective — even when they did not share an ideology — exhibited increased neural synchronization in a brain region involved in social cognition and perspective-taking while consuming political content. For those on the most extreme ends of the ideological spectrum, the effect was further enhanced by politically inflammatory language.
Unlike extreme ideologues who exhibited the most synchronized neural responses, politically moderate participants showed diverse responses to political content and did not have as intense reactions to inflammatory language.
“Together, our findings suggest that sharing an intense emotional response to political content helps explain why those at the far ends of the political spectrum come to view the world through a shared, extreme lens,” de Bruin said, adding that future research would focus on the relationship between emotion and extreme political beliefs.
The researchers acknowledged that their experiments represented just a small subset of political content, which warrants caution in generalizing the findings to all types of political content. They also noted that the study was conducted in the United States, and ideological extremity might be defined or experienced differently across other cultures and political systems.
Previous research by the same team explored how political ideology is associated with how people process political content in the brain. De Bruin said the new study, which involved the same participants, was inspired by political polarization in the current moment, in which people in societies around the world seem to be moving more toward the far ends of the political spectrum.
“It’s been established that political ideology can drive neural synchrony, but we can now also see that shared extremism, even from people with opposite ideologies, can also lead to similar brain responses,” de Bruin said.
FeldmanHall said that a better understanding of the mechanisms underlying more extreme views provides a starting point for how to encourage a more balanced perspective and promote common ground.
“When someone is so entrenched in their own extreme beliefs, it can be hard to think about how others might see the world,” FeldmanHall said. “I think it might be shocking to know that the way that their brain is processing information is very similar to someone who is on the other side of the spectrum, and who holds ideological beliefs that are diametrically opposed to theirs. And in that sense, it might be a useful way of making a vast political divide a little smaller.”