So Facebook showed us what we all secretly knew but didn’t want to admit: emotions are contagious, even online. You wouldn’t sit beside someone coughing without a mask, but you’ll marinate in their online misery for hours. Maybe it’s time we treat our feeds like our bodies—surrounding ourselves with uplifting content instead of the emotional equivalent of junk food. 'In 2012, Facebook conducted a study in which its data scientists manipulated the news feeds of 689,003 users. One set of users saw only negative posts for a full week, whereas the other set of users saw only positive posts. The goal was to measure how this affected their moods. What the data scientists discovered was evidence of emotional contagion. Just like you can catch a bad cold, you can catch a bad mood. “When positive expressions were reduced, people produced fewer positive posts and more negative posts; when negative expressions were reduced, the opposite pattern occurred,” according to the paper published in the scientific journal, The Proceedings of the National Academy of Sciences. “These results indicate that emotions expressed by others on Facebook influence our own emotions, constituting experimental evidence for massive-scale contagion via social networks.” Hidden Genius Polina Marinova Pompliano