Which brain networks activate when a person sticks to their beliefs?
To find out, researchers from a University of Southern California-led study used functional MRI scans, comparing results from whether and how much people changed their minds after being provided counterevidence for political and non-political issues.
"Political beliefs are like religious beliefs in the respect that both are part of who you are and important for the social circle to which you belong," said Jonas Kaplan, the study's lead author.
Functional MRI Study
Publishing their findings in the journal Scientific Reports, the researchers worked with 40 individuals who were self-declared liberals. Functional MRI scans were taken of each participant as they were presented eight political statements they said they believe in as strongly as another set of statements that are non-politcal. Five counter claims were then shown to them to challenge each statement they were provided. Every time a counter claim was presented, participants were tasked with rating their belief in an original statement from 1 to 7.
Based on responses from the participants, it appeared that people exhibit more flexibility when asked how strongly they believe in statements non-political in nature, "Albert Einstein was the greatest physicist of the 20th century." When presented with statements that would require a reconsideration of their political beliefs, the participants did not budge.
Brain Responses To Challenged Beliefs
After analyzing the results of the functional MRI scans, the researchers discovered that those who are least likely to change their beliefs showed more activity within the insular cortex and the amygdala compared to participants who were likely to be swayed by counterevidence.
According to Kaplan, these areas of the brain are important to decision-making and emotion, and may be related to how people feel when evidence against beliefs are presented. In particular, the insular cortex is responsible for processing feelings from the body and plays a key role in detecting stimuli's emotional salience, while the amygdala is specifically involved in how anxiety and threat are perceived. This leads to the idea that an individual that is feeling emotional, anxious, or threatened is less likely to change their minds.
Outside of politics, the results of the study could also be applied to responses to fake news stories. Kaplan said it should be acknowledged that people factor in emotions in deciding what is true or false, showing feelings play a role in cognition.
Other researchers for the study supported by Project Reason and USC's Brain and Creativity Institute include Sam Harris and Sarah Gimbel.