From Karlsen et al. (2017)

Another paper which challenges some conventional views of online ‘echo chambers’, i.e. the idea that on the internet and on social media, people largely live in a bubble of like-minded people, leading to a mutual reinforcing of views. Based on survey data from Norway, the authors note that most people encounter people with opposing views at least ‘sometimes’, although

.. this does not mean that they change their opinions. Debaters who say they are often contradicted also claim to emerge from online debates stronger in their beliefs.

While their experimental data tells us that

Both confirming and contradicting arguments affect attitude reinforcement in similar ways. This is true for both the self-reported reinforcement and attitude change reinforcement measures that we used in the study. One-sided confirming and contradicting arguments had stronger effects on reinforcement than two-sided neutral arguments. It is important to note that attitude strength is important in this picture. Effects are stronger for individuals with strong attitudes than individuals with moderate attitudes. However, this interaction effect is most consistent in the analysis based on self-reported reinforcement.

A practical tentative takeaway might be that to influence opinions, use extreme rhetoric if you’re dealing with moderates, and balanced two-side arguments if you’re dealing with die-hard fundies.

Instead of echo chambers, the authors suggest another metaphor:

Together, our results indicate that if a single metaphor is to be applied to online debating, trench warfare is a more fitting description than echo chambers. People are frequently met with opposing arguments, but the result is reinforcement of their original opinions and beliefs. However, the logic of confirmation bias, which is central to the echo chamber thesis, is also central in the notion of trench warfare. The Internet provides the opportunity to interact with like-minded people and those with opposite views at the same time. Interaction with like-minded people enables debaters to stay strong in their encounter with opposing arguments.

I’ve been toying for some time with the idea that in the current media environment, our main problem is not that people do not encounter opposing opinions and outgroup members; it is that they encounter them *too often* and in questionable contexts. I’m hoping to write more on that later, but the results here fit that idea quite nicely.

Karlsen, R., Steen-Johnsen, K., Wollebæk, D., & Enjolras, B. (2017). Echo chamber and trench warfare dynamics in online debates. European Journal of Communication.