Whether you are right-wing or left-wing, or neither. But how can we transcend the partisan divide when we consume the same political content but interpret it (at least some of us) through our own biased lenses?
Researchers from UC Berkeley, Stanford University and Johns Hopkins University scanned the brains of more than three dozen politically left- and right-leaning adults as they watched short videos featuring topical immigration policies, such as building a wall on the US-Mexico border and providing protection to undocumented immigrants under the Deferred Action for Childhood Arrivals (DACA) program.
The findings, published in the journal Proceedings of the National Academy of Sciences, show that right-wingers and left-wingers react differently to the same videos, especially if the content being watched contains words commonly used in political campaign messages.
Study lead author Yuan Chang Leong, a postdoctoral fellow in cognitive neuroscience at UC Berkeley, said, “Our study suggests that there is a neural basis to partisan biases, and some language especially drives polarization, In particular, the greatest differences in neural activity across ideology occurred when people heard messages that highlight threat, morality, and emotions.”
Overall, the results offer a never-before-seen glimpse into the partisan brain in the weeks leading up to arguably the most important US presidential election in modern history (this also applies to Turkey). The researchers underline that many factors, including personal experiences and the news media, contribute to what they call “neural polarization”.
Study author Jamil Zaki, a professor of psychology at Stanford University, said: “Even when presented with the same exact content, people can respond very differently, which can contribute to continued division, Critically, these differences do not imply that people are hardwired to disagree. Our experiences, and the media we consume, likely contribute to neural polarization.”
Why is there political polarization in society?
In particular, the study traces the source of neural polarization to a higher-level brain region known as the dorsomedial prefrontal cortex, which is believed to monitor and make sense of narratives, among other functions. Another key finding is that the closer a study participant’s brain activity is to that of the “average right-winger” or “average left-winger” as modeled in the study, the more likely the participant is to adopt the position of that group after watching the videos.
“This finding suggests that the more participants adopt the conservative interpretation of a video, the more likely they are to be persuaded to take the conservative position, and vice versa,” Leong says.
Leong and colleagues began the study with several theories about how people with different ideological biases would differ in how they process political information. They hypothesized that if sensory information such as sounds and visual images led to polarization, they would observe differences in brain activity in the visual and auditory cortices. However, if the narrative storytelling aspects of the political information people assimilated in the videos were dividing them ideologically, the researchers expected to see these differences manifest in higher-level brain regions such as the prefrontal cortex. And this theory turned out to be correct.
Your brain on politics
To find that attitudes toward strict immigration policies predicted both right-wing and left-wing biases, the researchers first tested questions on 300 people who identified to varying degrees as left-wing, moderate or right-wing. They then recruited 38 young and middle-aged men and women with similar socioeconomic backgrounds and education levels who expressed support for or opposition to controversial immigration policies such as building a wall on the US-Mexico border, DACA protection for undocumented immigrants, banning refugees from Muslim-majority countries from entering the US, and cutting federal funding to sanctuary cities.
Researchers scanned the brains of study participants via functional Magnetic Resonance Imaging (fMRI) while they watched two dozen short videos representing right-wing and left-wing positions on various immigration policies. The videos included news clips, campaign ads and snippets of speeches by prominent politicians.
After each video, participants rated on a scale of one to five how much they agreed with the overall message of the video, the credibility of the information presented, and the extent to which the video made them more likely to change their position and support the policy in question. To calculate group brain responses to the videos, the researchers used a metric known as inter-subject correlation, which can be used to measure how similarly two brains respond to the same message.
What Does Political Polarization Look Like in the Brain?
Their results showed a high group-wide common response across the auditory and visual cortices, regardless of participants’ political attitudes. However, neural responses diverged along partisan lines in the dorsomedial prefrontal cortex, where semantic information or word meanings are processed.
Next, the researchers went deeper to learn which specific words led to neural polarization. To do this, they divided the videos into 87 short segments and placed the words in the segments into one of 50 categories. These categories included words related to morality, emotions, threat and religion. The researchers found that the use of words related to risk and threat and morality and emotions led to greater polarization in the neural responses of the study participants.
Risk, threat, emotional, moral
Overall, Leong said, the results of the study show that political messages that contain threats and use moral-emotional language lead partisans to interpret the same message in opposite ways, contributing to increased polarization.
Going forward, Leong hopes to use neuroimaging to build more precise models of how political content is interpreted and to inform interventions aimed at narrowing the gap between right-wingers and left-wingers.
Reference: Leong, Y. C., Chen, J., Willer, R., & Zaki, J. (2020, October 20). Conservative and liberal attitudes drive polarized neural responses to political content. Proceedings of the National Academy of Sciences, 117(44), 27731–27739. https://doi.org/10.1073/pnas.2008530117 Hot-button words trigger conservatives and liberals differently | Berkeley News
Leave a Reply