"Feeling down? Having a stimulating conversation might help." Scientific American looks at a study suggesting that deep conversations are more satisfying that superficial ones. "Researchers at the University of Arizona and Washington University in St. Louis used unobtrusive recording devices to track the conversations of 79 undergraduate students over the course of four days...The happiest subjects spent 70 percent more time talking than the unhappiest sub jects, which suggests that 'the mere time a person spends in the presence of others is a good predictor of the person’s level of happiness,' says co-author Matthias Mehl, a psy chologist at Arizona."