There was a time when emotions were considered a weakness, getting in the way of good thinking. We now know emotions can result in powerful changes to our bodies and actual physical responses.

Think about what happens when we are afraid of something. The amygdale — the small almond-shaped region housed deep in the brain sends a variety of signals to the rest of the cortex that engages our attention to the situation at hand, setting our heart and breath racing, changing our facial expressions, tensing our muscles, and starting us sweating. Eventually, the limbic system our brain’s emotional circuitry sends important information to the frontal lobes, helping us to put our feelings in context.

We now know our emotions are not a sign of weakness, that they do matter as an important tool in our brain's arsenal. For example, scientists have recently tackled the link between emotions and political beliefs, noting that political attitudes can be affected by emotions and that anxiety can be generated by political information or events.

In 2012, research at the University of South Carolina suggested that choosing a political candidate may depend largely on our biological make-up, and that Democrats and Republicans are hard-wired differently and may be naturally inclined to hold varying, often opposing, perceptions and values.

It is thought that politics is a battle of ideas and beliefs. And challenges to our political beliefs have been particularly evident over the last year. The 2016 presidential election was fraught with emotion and often-heated controversies that played out across many different forums throughout society.

But exactly what happens in our brains when our political beliefs are challenged? How flexible are we to reconsidering our political positions?

Scientists at the Brain and Creativity Institute at USC Dornsife College of Letters, Arts and Sciences discovered that when our political beliefs are challenged with contradictory evidence, we actually become more hard-headed. To determine which brain networks respond when we hold firmly to our beliefs, the researchers at USC compared whether and how much we change our minds on nonpolitical and political issues when presented with a counterargument.

Forty healthy participants were recruited from the University of Southern California community and the surrounding Los Angeles area. Each participant read eight political statements (e.g., "Abortion should be legal" and "Taxes on the wealthy should generally be increased") and eight nonpolitical statements on health (e.g., "Taking a daily multivitamin improves health"), education (e.g., "A college education generally improves a person’s economic prospects") and history (e.g., "Thomas Edison invented the light bulb") with which they had previously indicated strong agreement.

Each statement was followed by five challenges. Each challenge was a sentence or two that provided a counterargument or evidence against the original statement, often containing exaggerations or distortions of the truth. Participants rated the strength of their belief in the original statement on a scale of 1-7 after reading each counterclaim.

To determine the areas of the brain that became most engaged during the challenge questions, the researchers studied participants' brain scans (General Linear Model). What researchers found was that although participants did not change their beliefs much, if at all, when provided with evidence that countered political statements, their beliefs weakened by one or two points when challenged on nonpolitical topics, and they had more activity in the amygdalae and the insular cortex, compared with people who were more willing to change their minds.

The researchers were not surprised that study participants were especially resistant to arguments against their political beliefs. Post-challenge belief strength was reduced for both political and nonpolitical statements, indicating that the counter-evidence did, at least temporarily, affect reported belief strength.

However, the change was significantly greater for nonpolitical beliefs. Follow-up questionnaires completed weeks later showed that reduced belief strength persisted for the nonpolitical beliefs. Participants who rated the challenges as more credible were more likely to change their minds, and it is well known that the credibility of the source greatly influences persuasion.

This study supports the theory that the amygdala in particular is known to be especially involved in perceiving threat and anxiety and is consistent with the theory that the insular cortex processes feelings from the body. The bottom line is that we are less likely to change our minds when we feel threatened, anxious or emotional.

According to Sarah Gimbel, a research scientist at the Brain and Creativity Institute, knowing how and which statements may persuade people to change their political beliefs could be a critical component in the progress of our society.