Dialog on most topics tends to not result in heated verbal exchanges, but move on to either strongly embraced politics or religion ideas and you may find that verbal a whiplash is soon being deployed.

What is going on here, why is it like this?

What is even more fascinating is that even when faced with mountains of evidence that conflicts with a stance being taken, people simply hunker down and stick to the stance.

A new study offers some interesting insights into why it is like this.

Neural correlates of maintaining one’s political beliefs in the face of counterevidence

The paper is open access and published within nature. It has been authored by Jonas T. Kaplan  & Sarah I. Gimbel of the Brain and Creativity Institute and Department of Psychology, University of Southern California, along with Sam Harris of Project Reason Los Angeles, CA. Yes, that is the semi-famous Sam Harris that many of you might know about. Don’t be shocked, he is a cognitive neuroscientist, so this is all part of his day job.

The abstract explains what they did and what they found …

People often discount evidence that contradicts their firmly held beliefs. However, little is known about the neural mechanisms that govern this behavior. We used neuroimaging to investigate the neural systems involved in maintaining belief in the face of counterevidence, presenting 40 liberals with arguments that contradicted their strongly held political and non-political views. Challenges to political beliefs produced increased activity in the default mode network—a set of interconnected structures associated with self-representation and disengagement from the external world. Trials with greater belief resistance showed increased response in the dorsomedial prefrontal cortex and decreased activity in the orbitofrontal cortex. We also found that participants who changed their minds more showed less BOLD signal in the insula and the amygdala when evaluating counterevidence. These results highlight the role of emotion in belief-change resistance and offer insight into the neural systems involved in belief maintenance, motivated reasoning, and related phenomena.

And that means?

OK, so this is what they did.

About 40 study participants were presented with arguments that contradicted their strongly held political and non-political views. As this happened, neuroimaging was utilised to see what was going on inside their heads … literally.

What is already known is that people often resist changing their beliefs when directly challenged, especially when these beliefs are central to their identity. In fact we also know that it gets rather weird, because often exposure to counter-evidence may even increase a person’s confidence that his or her cherished beliefs are true. So the researchers asked themselves this question …

What are the neural systems involved in protecting our most strongly held beliefs against counter-evidence?

One psychological theory regarding why it is like this is that when we experience negative emotions due to conflicting information, we cope by thinking in ways that will minimize the impact of the challenging evidence: discounting its source, forming counterarguments, socially validating their original attitude, or selectively avoiding the new information. The degree to which this happens will be very much determined by the personal significance of the challenged belief.

If this model is correct, then what naturally falls out is a prediction about the neural systems that govern resistance to belief change. Obviously the emotional parts of our brains should trigger when evidence that conflicts with deep beliefs is presented.

To explore all this, they used an MRI scanner to see what parts of the brain were lighting up for the 40 selected individuals, chosen because they strongly held to specific political views – liberals of deep conviction.

Prior to the scan their belief strength for specific statements was measured. During the MRI scan they were then given challenging counterarguments. After the scan their belief strength was again measured to see if the degree of confidence they had originally expressed had changed.

They did this for both political and also non-political statements, and for all of that they now had precise measurements of brain activity.

What did they Predict?

Basically that the political views would resist being changed and that the non-political statements would change minds. They expressed all that like this ..

We predicted that the political condition would result in less belief change than the non-political condition, and that resisting challenges to political beliefs would be associated with increased activity in brain systems involved in contemplating identity and internally-focused cognition. Furthermore, we predicted that there would be a relationship between activity in emotion-related brain structures and individual differences in persuadability. We also sought to identify brain activity that correlated with the strength with which specific beliefs were maintained in our sample.

So what happened?

• As predicted, the belief strength for the non-political statements decreased and not so much for the political ones.
• They followed up a few weeks after the test and also discovered that the decreases measured had persisted.

And the Imaging?

Side note it is worth understand the following term that they deploy.

• default mode network [DMN]—a set of interconnected brain structures associated with self-representation and disengagement from the external world

That was quite revealing …

Processing challenges to political beliefs was associated with relatively increased activity in regions of the DMN, including the precuneus, the posterior cingulate cortex, the medial prefrontal cortex, the inferior parietal lobe, and the anterior temporal lobe. The opposite contrast showed increased activity in the dorsolateral prefrontal cortices and the orbitofrontal cortices bilaterally for non-political challenges compared with political challenges.

Yes, but what does this actually tell us?

It confirms what we already knew – If you engage and discuss deeply help beliefs, then do not expect evidence and argument to initiate a change of mind. It also verifies the psychological theory behind it.

Political and religious beliefs are part of who we are and are also vitally important for the social circles we move within.

The study reveals that when challenging an idea, if the idea is part of our identity, then distinctly different parts of the brain activate – the parts that invoke an emotional response. The more active these emotional regions such as the amygdala and the insula became, the greater the degree of resistance to a change of mind will be.

To use the precise words within the study …

The brain’s systems for emotion, which are purposed toward maintaining homeostatic integrity of the organism, appear also to be engaged when protecting the aspects of our mental lives with which we strongly identify, including our closely held beliefs.

This might all appear to be dull and uninteresting, but … and this is key … we live in an age when rather a lot of quite frankly absurd ideas are starting to gain traction and dominate. Evolution is a myth, Climate Change is a myth, oil and coal is the way forward, we need to build walls (that will do nothing), or abandon the EU, or … well you get the idea, I need not remind you of things that are overly familiar.

The point is this – people are embracing such thinking as a core part of their identity, and that renders then immune to reason and evidence.

the inability to change another person’s mind through evidence and argument, or to have one’s own mind changed in turn, stands out as a problem of great societal importance.