Social scientists have long known how to turn liberals into conservatives in the lab - all they have to do is scare them.

"Research has shown that you can make liberals more conservative by threatening them and making them somewhat afraid," Yale psychology professor John Bargh writes in his new book, "Before You Know It: The Unconscious Reasons We Do What We Do," which was released Tuesday.

Several studies have shown that when social scientists get liberal-leaning experiment subjects to think about their own deaths or make them feel threatened, some left-wingers adopt more conservative values. This phenomenon played out after 9/11 -- researchers found that there was a "very strong conservative shift" in the US after the attacks, with more liberals supporting Republican President George W. Bush and favoring increases in military spending.

The hypothesis social scientists developed about this effect is perhaps best summed up in a 2003 review of research on the subject: "People embrace political conservatism (at least in part) because it serves to reduce fear, anxiety, and uncertainty; to avoid change, disruption, and ambiguity; and to explain, order, and justify inequality among groups and individuals," it said.

There's evidence that this fear plays out in how conservative and liberal brains are shaped, too. Researchers have taken brain images of people with different political leanings and found that those who self-identify as conservative have larger and more active right amygdalas, an area of the brain associated with the expression and processing of fear. A 2011 study looked at MRI scans of self-described conservative young adults and found they had more grey matter volume in the right amygdala than their liberal counterparts. In 2013, another team of scientists expanded that research to show that conservatives generally have more activity in their right amygdala when taking risks than liberals do.

But while inducing fear might shift a liberal mindset, conservatives have generally been more difficult for social scientists to sway in experiments -- until now.

In his new book, Bargh details two separate experiments that he conducted with his colleagues that swayed folks who identified as conservative to express more liberal attitudes.

(Jeremy Corbyn has amassed a large amount of dedicated supporters since he became Labour leader, Getty) (Jeremy Corbyn has amassed a large amount of dedicated supporters since he became Labour leader)

How They Did It

The researchers behind the psychology experiment told a group of participants to imagine that they'd been granted a superpower by a magic genie and were suddenly as invincible as Superman -- bullets bounced off them, fire couldn't scorch their skin, and "a fall from a cliff wouldn't hurt at all," Bargh writes in his book. The study's control group was simply told to imagine they could fly.

Then the researchers asked the participants to weigh in on some political statements, including whether they "would be reluctant to make any large-scale changes to the social order," and whether "it's okay if some groups have more of a chance in life than others."

Liberal participants' attitudes on social issues didn't shift at all. The conservative participants, on the other hand, started adopting more liberal views on social issues (though not economic ones.)

Participants who imagined themselves with the ability to fly had no change in their political views.

The study authors say this is some of the first experimental evidence that making people feel completely safe can (temporarily) change their politics and make them more liberal.

What Else Are We Doing Unconsciously?

Bargh argues in his book that these results are but one example of the way humans are still living with the "hard-won lessons" of evolution.

"The fundamental drive for physical safety is a powerful legacy of our evolutionary past" he writes. "It exerts a pervasive influence on the mind as it navigates and responds to modern life, often in surprising ways -- like who you vote for."

Bargh's book suggests that a myriad of unconscious influences impact our everyday decisions. Holding a cup of piping hot coffee can make us friendlier, he suggests, becuase the association between physical warmth and social warmth is something we learned unconsciously as infants when we were held close to a loved one's warm chest.

In another study, Bargh showed how washing hands with soap and water can make people less hostile to individuals who are different than they are. Bargh says that's because to some extent, our modern prejudices are shaped by the way we've evolved to avoid unknown, foreign threats like disease.

In general, Bargh writes, people "don't fully understand why we do what we do all of the time."

"We have one mind, and it can operate consciously and unconsciously," he told Business Insider. But Bargh says that's generally not a bad thing. He believes the unconscious forces at play are generally "on our side," since they help us get through the day without needing to reason through every decision we make.

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