The wave of social media in recent years has changed how people think, read and "talk." As in other countries, Japan's Facebook, Twitter, Mixi, Line and other social media have become primary means of exchange, interaction and discussion. A new American study, though, finds that most people who regularly use social media sites were actually less likely to share their opinions, either online or in person.

In the study of regular social media users in America, researchers from the Pew Research Center noted that most people either expected their online contacts to agree with them or did not feel comfortable expressing an opinion through such media.

In other words, social media were rarely used for starting a political discussion. The survey found people willing to speak up or stay silent depending on several factors: how confident they were in what they know about an issue; the intensity of their opinion on the issue; and their level of interest in that issue.