If you enjoy sharing all your likes and dislikes on Facebook, you’re definitely not alone: research finds that broadcasting personal opinions gives people the same sense of reward as earning money. The study is in the Proceedings of the National Academy of Sciences. [Diana I. Tamir and Jason P. Mitchell, "Disclosing information about the self is intrinsically rewarding"]

Study subjects had their brains scanned while they either talked about their opinions or judged the beliefs of another. And sharing their own point of view stimulated more activity in the reward-processing parts of the subjects’ brains.

In another experiment, participants got to choose among reporting their own opinion, judging someone else's opinion or answering a true or false question. And for each choice, they could earn varying amounts of money.

Rather than maximize their winnings by answering the questions that were worth the most cash, people preferred to talk about themselves—even though they sacrificed an average of 17 percent of their potential earnings to do it. For the participants, sharing personal information was its own reward.

Which means that people like comedian Patton Oswalt, who tweets photos of what he's having for lunch, probably feel like a million bucks.

—Sophie Bushwick