But breaking the bubble, it turns out, might not work. It might even backfire. Despite decades of psychology research that shows fostering contact between "us" and "them" is a powerful way to reduce prejudice, scientists are starting to find that you can't just shove people together — online or in person — and expect the interaction to have miraculous effects.
Far from bridging the gap, the wrong kind of contact might even entrench people deeper in their partisan views.
That became crystal clear to Christopher Bail, a sociologist who heads the Duke University Polarization Lab, after he designed an experiment to disrupt people's echo chambers on Twitter. Bail assigned Republicans and Democrats to follow automated accounts that retweeted messages from the elected officials, thought leaders and think tanks from the other side.
Far from finding a digital utopia forged from mutual understanding, the two sides drifted apart, Bail and his colleagues reported in the Proceedings of the National Academy of Sciences. After a month, Republicans exposed to the Democratic account became much more conservative, while Democrats exposed to Republican tweets reported slightly more liberal views.
Bail noted that the small difference in Democrats' views could have been caused by chance, but even so, despite having a more diverse news feed, neither Republicans nor Democrats became more sympathetic to the other side.
Bail took a dose of his own medicine and followed both accounts — which retweeted people such as @LouDobbs and @EricTrump to Democrats or @SenKamalaHarris and @ariannahuff to Republicans. Bail said he was surprised to see how frequently the accounts weren’t in conflict but were simply tweeting about entirely different issues. He said can't be sure how the tweets had their effect in his study, but he pointed to a recent, counterintuitive body of research chronicling backfire effects.
“If you expose someone to an opposing view, their first instinct is to counter-argue it, and by virtue of counter-arguing and coming up with lots of reasons they might disagree with it, they’re left with more reasons to disagree than they had to begin with,” Bail said.
Those results resonate with Donghee Jo, an economist at Northeastern University, who has been studying a related question in South Korea and also found, to his surprise, that people who stay in their bubbles moderate their extreme views more than those exposed to diverse news sources.
"The next question is: What are the exact conditions it goes in the opposite direction?" Jo said.
A new study in the Proceedings of the National Academy of Sciences helps answer it. Researchers presented conservatives and liberals with a NASA graph that showed changes in sea level ice, and asked them to extrapolate how much sea ice would be left in the Arctic by 2025. While the trend of the graph was clearly down, there was a slight uptick in the last year, 2013.
About a quarter of liberals incorrectly interpreted the graph, saying it predicted sea ice would increase, while 40 percent of conservatives got it wrong.
In a second try, one group of people got to see how others answered the question, on average. Another group got an average answer, along with a completely gratuitous decorative flourish — the Republican and Democrat logos, elephants and donkeys. The logos were just taking up space on the screen, not conveying a bit of information, but they had a powerful effect on people's ability to interpret the new information.
Liberals and conservatives who got only the anonymous average answer markedly improved their accuracy so that close to 90 percent in both groups answered correctly. Those who got the same information with the logos at the bottom of the screen barely improved.
Damon Centola, a sociologist at the University of Pennsylvania's Annenberg School for Communication who led the study, thinks this finding may provide a clue as to why it could appear that contact with others might backfire on Twitter.
"The problem is they’re mistaking the cause. It's not that communication causes polarization. It’s that communication in a highly polarized context increases polarization," Centola said. Take away any reminder of partisanship, his study suggests, and people can absorb information rationally.
Starching out people's partisan signals may not be feasible for an online platform where part of the attraction, judging by people's user photos and Twitter bios, is identifying with a side. But it adds to a growing effort to understand the possibilities and limits of one of the most influential ideas in psychology about how to increase tolerance, in various contexts.
The "contact hypothesis" has been supported by hundreds of studies that show bringing two groups face-to-face is a way to unearth common ground and reduce prejudice. But researchers have recently revealed that the details of how to use contact as a systematic tool to decrease racism or ethnic tension in the real world is still poorly understood.
“It’s been a pillar in the psychology literature. Everyone teaches it when you do Psych 101 and intergroup conflict,” said Betsy Levy Paluck, a psychologist at Princeton University, who recently published a comprehensive analysis of the evidence behind the idea.
"The contact hypothesis," Paluck found, "isn't supported with as much evidence as you thought."
That doesn't mean that the idea doesn't hold up; her study found that contact between two groups did typically reduce prejudice. But the strength of the effect could depend on the kind of bias — contact was very effective at reducing prejudice against disabled people, for example. But it was virtually untested on topics such as racial and ethnic tensions, revealing a huge knowledge gap about how it could be used in real-world scenarios.
Ryan Enos, a political scientist at Harvard, recently conducted an experiment in which he surveyed people waiting on commuter rail platforms at rush hour about their views on immigration. Five days later, a pair of Hispanic people began appearing at the same time and speaking to each other in Spanish as the commuters waited for the trains. Either three or 10 days after the Spanish speakers first appeared, the commuters were surveyed again. The passengers became more in favor of limiting immigrants from Mexico and against allowing employed, undocumented immigrants without a criminal history to stay than they were before the intervention, Enos found.
“The situations in which contact doesn’t work, when it leaves this backlash, is when people are close but far away,” Enos said. “They can see each other, but they’re segregated and don’t have meaningful contact.” That’s what happened on the train platform in Boston — and what frequently happens online, where personal interaction is part of a constantly unfurling stream.
He also noted that the social media era may provide a particular challenge to quelling polarization. The original formulation of the “contact hypothesis” involved a central authority that was urging people to get along and treat each other as equals.
“If you think about the situation of American politics, right now,” Enos said, “it’s the exact opposite.”