The symptoms: The woman visited a clinic because she had long experienced bursts of uncontrollable laughter, which doctors described as "mirthless" in a report of her case. According to the patient, ...

Laughing is something you do with virtually no thought. Your friend tells a funny joke? You chuckle and don’t think twice about it. And there’s a reason for the adage “laughter is the best ...

Think about all the times you’ve laughed with your friends: the late-night giggles, the completely ridiculous inside jokes, or the perfectly timed sarcastic comment that left you and your friends ...