Commentary and some more information from The New Yorker:
No one joins Facebook to be sad and lonely. But a new study from the University of Michigan psychologist Ethan Kross argues that that’s exactly how it makes us feel. Over two weeks, Kross and his colleagues sent text messages to eighty-two Ann Arbor residents five times per day. The researchers wanted to know a few things: how their subjects felt overall, how worried and lonely they were, how much they had used Facebook, and how often they had had direct interaction with others since the previous text message. Kross found that the more people used Facebook in the time between the two texts, the less happy they felt—and the more their overall satisfaction declined from the beginning of the study until its end. The data, he argues, shows that Facebook was making them unhappy.