Why ’I’m so happy I could cry’ makes sense

The phrase "tears of joy" never made much sense to Yale psychologist Oriana Aragon. But after conducting a series of studies of such seemingly incongruous expressions, she now understands better why people cry when they are happy. "People may be restoring emotional equilibrium with these expressions," said Aragon, lead author of work to be published in the journal Psychological Science. "They seem to take place when people are overwhelmed with strong positive emotions, and people who do this seem to recover better from those strong emotions." There are many examples of responding to a positive experience with a negative emotion. A crying spouse is reunited with a soldier returning from war. Teen girls scream at a Justin Bieber concert and so do soccer players as they score a winning goal. The baseball player who hits a winning home run is pounded at home plate by teammates.