Scientists have found the psychological signature of people who are likely to hold dogmatic or extremist views.

It makes sense, the researchers said, as people who are dogmatic tend to be impulsive but also slow to process perceptual information. Extremists — regardless of whether they are right-wing or left-wing — also tend to struggle with complex cognitive tasks, but they have a high tolerance for risk, according to the new study, published Sunday (Feb. 21) in the journal Philosophical Transactions of the Royal Society B.

"They tend to seek out sensations and thrills and risks," study lead author Leor Zmigrod, a psychologist at the University of Cambridge, told Live Science. "And that's really congruent with what we can imagine about the individual who is willing to go and fight and commit violence for their cause."

Related: Fight, fight, fight: The history of human aggression

The basis of belief

The study isn't the first to try to connect political ideology to more basic psychology, but simple narratives are hard to come by. About a decade ago, multiple studies began to reveal that conservatives were more sensitive to disgust than liberals, but more recent work has failed to find similar results. Similarly, research suggesting that conservatives are more worried about threats than liberals may have defined both threats and ideology too narrowly: In a recent study published in the journal Personality and Social Psychology Bulletin, researchers looked at people from around the world, and using a broad definition of threats, they found no evidence that conservatives are actually more cowardly.

For many of these studies, scientists relied on self-reporting and tried to link a single ideology to a single cognitive or emotional trait, Zmigrod said. She and her colleagues took a broader view: They didn't hypothesize about what cognitive or personality traits might be linked to which ideological views. Instead, they put 522 people through 37 cognitive tasks and 22 personality surveys. The cognitive tasks were very basic. For example, a participant would view a screen full of moving dots and would have to quickly answer whether most of the dots were moving left or right.

From the answers, Zmigrod said, "you can start to infer how they are processing information from the environment."

In the second phase of the study, the participants were invited to respond again to a set of surveys about their political beliefs and the strengths of those beliefs; 334 of the original participants agreed to respond.

Cognition, personality and ideology

With this wealth of responses, the researchers were able to find correlations between particular cognitive and personality traits and ideology. Zmigrod's previous work has found that extremism and dogmatism on either side of the political spectrum are linked to a lack of cognitive flexibility, which is the ability to think about concepts simultaneously or switch between ways of thinking. (Cognitive flexibility is often tested by giving people a task and then changing the rules of that task partway through. More flexible people will adapt more quickly to the new rules.)

The new study also suggested that dogmatism and extremism are linked to slower, more strenuous processing. People who are dogmatic may process information imperfectly and then act impulsively on that information, the researchers found. Extremists — defined as people supportive of violence to protect their ideological in-group — were thrill seekers in personality but were slow in working memory, or the ability to keep information in mind while conducting a task. They also used fewer perceptual strategies to solve problems.

"They tend to perform more poorly on these complex high-level processing tasks," Zmigrod said.

The researchers also found that people with nationalistic and politically conservative ideologies showed more caution in perceptual decision making, reducing their speed, rather than their accuracy, when challenged to a time-sensitive task.

"That's really fascinating because caution really is almost a synonym for conservatism," Zmigrod said.

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These psychological traits explained far more of the variation between people than demographic information alone. Demographics, for example, explained 7.43% of the difference between people in political conservatism, while demographics plus psychological traits explained 32.5%. Demographics alone explained only 1.53% of the variation in dogmatism between people, while a combination of demographics and psychological traits explained 23.6%, or 15 times more.

The research raises the question of whether strategies to improve people's cognitive flexibility or information processing might make them more resistant to developing extremist views, Zmigrod said. The researchers are also planning to study how these psychological traits are linked to genetics and brain functioning; those findings, in turn, could help tie together how people's experiences interact with their psychology.

"We're trying to see how environments might interact with personal vulnerability to make a person extreme or dogmatic," Zmigrod said.

Originally published on Live Science.