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.