The negative impact of deranged Internet comment trolls on reader opinion has already been documented. Last year, researchers at the University of Wisconsin-Madison found that readers exposed to invective in comment sections at the end of a fictitious article about nanotechnology were more likely to develop “polarized” interpretations of its content. That finding was one reason why Popular Science, which argued that the negative effect was particularly pronounced when it came to scientific discourse, shut down its comment sections. (Other publications, including Pacific Standard, have done the same.)

 

Now, a new study from the Journal of Computer Mediated-Communication has measured the more general impact of comments on a different kind of online content: anti-smoking Public Service Announcements. And the results are quite counter-intuitive. ...

 

Unsurprisingly, PSAs with negative, uncivil comments received the lowest effectiveness ratings. But the PSAs with the very highest effectiveness ratings were not the ones with a bevy of positive, civil comments. The PSAs rated as most effective did not have any comments at all.