New York, Dec 24 (IANS) If you closely followed the recently concluded US presidential election, you might have already realised what a new study confirms - providing contradictory evidence to change one's political beliefs may actually backfire.

People become more hard-headed in their political beliefs when provided with counter-evidence because the brain may perceive the challenges to political beliefs in the same way it perceives threat and anxiety, the study suggests.

"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 lead author Jonas Kaplan from University of Southern California in the US.

"To consider an alternative view, you would have to consider an alternative version of yourself," Kaplan said.

To determine which brain networks respond when someone holds firmly to a belief, the neuroscientists compared whether and how much people change their minds on nonpolitical and political issues when provided counter-evidence.

They discovered that people were more flexible when asked to consider the strength of their belief in nonpolitical statements -- for example, "Albert Einstein was the greatest physicist of the 20th century".

But when it came to reconsidering their political beliefs, such as whether the US should reduce funding for the military, they would not budge.

"I was surprised that people would doubt that Einstein was a great physicist, but this study showed that there are certain realms where we retain flexibility in our beliefs," Kaplan said.

For the study, the neuroscientists recruited 40 people who were self-declared liberals. 

The scientists then examined through functional MRI how their brains responded when their beliefs were challenged.

The study - published in the journal Scientific Reports - found that people who were most resistant to changing their beliefs had more activity in the amygdalae (a pair of almond-shaped areas near the center of the brain) and the insular cortex, compared with people who were more willing to change their minds.

"The activity in these areas, which are important for emotion and decision-making, may relate to how we feel when we encounter evidence against our beliefs," Kaplan said.

"The amygdala in particular is known to be especially involved in perceiving threat and anxiety," Kaplan added. 

"The insular cortex processes feelings from the body, and it is important for detecting the emotional salience of stimuli. That is consistent with the idea that when we feel threatened, anxious or emotional, then we are less likely to change our minds," Kaplan explained.

He also noted that a system in the brain, the Default Mode Network, surged in activity when participants' political beliefs were challenged.

"These areas of the brain have been linked to thinking about who we are, and with the kind of rumination or deep thinking that takes us away from the here and now," Kaplan said.