Political differences are embedded in people’s brain structure, with people with conservative or liberal views reacting differently to current issues such as abortion or immigration, according to a new study.
The American study at Brown University found that those who share a certain political belief process information differently than those with opposing views.
A 2021 experiment led by Oriel FeldmanHall, associate professor of cognitive, linguistic and psychological sciences, with the Carney Institute of Brain Science at the university measured the brain activity of people who described themselves as politically liberal or politically conservative while watching videos about culturally sensitive topics such as abortion and immigration.
The study showed that the brains of participants who shared political beliefs responded in a similar way.
Based on this research, a study published Feb. 1 in the journal Science Advances looked at how people with “synchronized neural fingerprints” interpreted different words. The group of 44 participants were asked to rank words such as “abortion” and “immigration”, “American” and “police” according to their perceived similarity. They were also asked to press a button to indicate whether the words they were shown were political or not.
Participants were also shown “neutrally worded” news clips and a vice presidential campaign debate about police brutality, with their brain activity measured. Based on measured brain activity, immigration appeared to be the most polarizing topic for participants, followed closely by abortion, while policing as a topic was less polarizing.
Findings showed that people who shared political beliefs responded similarly to the words – even without any political context.
‘Neural Fingerprint’
Prof FeldmanHall said: “The reason two liberal brains synchronize when watching a complicated video is partly due to the fact that each brain has neural fingerprints for political concepts or words that are very much aligned.”
He said the study helped “shed light on what happens in the brain that gives rise to political polarization.”
“You can think of it as the brain representing the word by firing neurons in a certain way. It’s almost like a fingerprint, a neural fingerprint that encodes the concept of that word in the brain.”
The researchers said the findings could help provide insight into how a controversial news channel elicits vastly different political opinions from its audience.
Prof FeldmanHall added: “The problem of political polarization cannot be tackled on a superficial level.
“Our work showed that these polarized beliefs are very deep-rooted and go all the way back to how people perceive a political word. Understanding this will influence how researchers think about possible interventions.”
Conservatism linked to fear in the brain
Previous studies have suggested that people with politically conservative views have larger areas of the brain associated with fear and anxiety than people with left-wing views.
A 2010 University College London study found that those who are politically conservative have larger amygdalas, the area of the brain associated with emotion, and a smaller anterior cingulate – the area of the brain associated with courage and a positive view.
The research, originally commissioned by actor Colin Firth, showed that political differences can be hardwired into people’s brain structures.
A 2013 study also found that American Republican voters had a more active right amygdala, a region involved in defensive “fight or flight” responses, while Democrats showed significantly more activity in the left insula, a brain region associated with social and self awareness.
The team of British and American scientists were able to predict with an accuracy of 83 percent whether people voted Republican or Democrat simply by studying their brain activity.