To an astounding and increasing degree, “viral” “content” is shaping people’s perceptions of the world. A 2015 survey found that 63 percent of U.S. Facebook users (or over half the population) get their news on the platform, with similar percentages for Twitter users and even higher for Redditors. And with so much of the work of the digital newsroom being devoted to hopping on freshly minted memes — whether Chewbacca masks or white Vans — understanding why some pieces bounce hyperkinetically around the web and others flop is high-stakes research. Plus, it helps us see how humans live online.

To that end, an Italian-French study presented at the World Wide Web Conference provides some really interesting insights for anyone interested in how human beings respond to the buzzing maelstrom of content bearing down on them whenever they go online. Marco Guerini of the Italian research institute Fondazione Bruno Kessler and Jacopo Staiano of the Sorbonne drew on the largest-yet virality data set to better understand the emotions that drive sharing. The set wasn’t just large, but elegant: Guerini and Staiano chose articles from two publications (the social news site Rappler and the popular Italian newspaper Corriere della Sera) where users can express their “affective feedback” to a piece via click, similar to the emoji reactions that Facebook rolled out last February.