Love hurts. We all know this. But a recent study suggests that rejection really does cause physical pain. Learn more on this Moment of Science.
These particular subjects were then matched with people they had not met before to play a game in which the winner was able to blast the loser with an unpleasant noise, the intensity and duration of which were adjustable by the winner.
Laughter research has found that less than 20% of laughter is a sincere response to someone's humor. In fact, it's primarily a social signal.