In an era of increasing ideological polarisation, many people are trying – and struggling – to understand the minds of those holding opposing views.

We often look to age, gender or education to explain divisions. We analyse campaign strategies and the language politicians use to win our support. My colleagues and I at the University of Cambridge chose to turn to cognitive psychology for more answers.

In a study of over 300 UK citizens, we tested participants’ tendencies towards “cognitive flexibility” – their ability to adapt to change – and “cognitive persistence”, which reflects a preference for stability and uniformity.

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We found that people who displayed higher cognitive flexibility were less likely to support authoritarian and nationalistic ideologies. They were also more likely to think the UK should remain in the EU.

Those who exhibited tendencies towards cognitive persistence were more likely to endorse conservative and nationalistic attitudes. They, in turn, were more likely to support Brexit.

Adapting to change

We measured cognitive flexibility by asking participants to complete tests which assessed their cognitive information processing styles. These tests do not make any reference to politics or ideologies.

In one test, participants were presented with four cards featuring different geometric figures of various colours and shapes. The participants were asked to match a fifth card from a separate deck to one of these four cards. There were multiple potential rules for matching the cards. They could be matched according to the colour, number, or shape of the geometric figures.

At the start of the task, participants learnt an initial rule for classifying the cards (for example, according to colour). But after learning the rule, the classification rule suddenly changed (for example, they now needed to match the cards according to shape). This allows us to measure how easily individuals adapt to change. Do they quickly change their responses to the new rule (which is indicative of flexibility)? Or do they tend to persist with the previously learnt rule (which is a marker of persistence)?

Across multiple behavioural measures, we found a link between mental flexibility and nationalistic ideology. We asked participants about their support for immigration, the European Union, free movement of labour, and access to the EU single market. We found that cognitive flexibility and tolerance for uncertainty were related to support for flexible immigration and fluid national borders. Cognitive persistence was linked to opposition to immigration and free movement of labour.

A similar pattern emerged when we asked participants about the extent to which they agreed with the statement: “The government has a right to remain in the EU if the costs of Brexit are too high.” We found that the belief that the UK government ought to be flexible in its implementation of Brexit in light of potential costs was positively correlated with cognitive flexibility. Psychologically flexible individuals appear to evaluate policies in more flexible, context-dependent ways.

Our ideological stances may therefore be tied to our general psychological adaptability to change.

Head and heart

These findings suggest that we don’t just vote with our hearts, we also vote according to our cognitive style. In fact, the results imply a parallel between our cognitive preferences and our ideological preferences. The flexibility with which we process non-political and non-emotional information reveals how flexibly we process ideological arguments.

Our study points to general trends and tendencies rather than the psychological characteristics of any particular individual. It’s important to remember that the reasons behind why we vote the way we do are varied, idiosyncratic and complex. Cognitive flexibility is only one piece of an intricate puzzle.

But understanding the psychological processes that underpin our ideologies and voting choices will help us to better understand each other. That’s a crucial step towards bridging the echo chambers and ideological gaps that often divide our families, our communities and our world.