Science & Theology News rounds up some of the recent studies of oxytocin and trust, adding one I haven't seen before. According toJ. Keith Murnighan and Robert Lount, researchers at the Kellogg School of Management at Northwestern University, happy people are more trusting than sad people.

Writer Mike Martin quotes Murnighan as saying,

"Research on happiness suggests that it reduces mental processing — we work less hard cognitively. We might miss subtle cues when we are happy that we would otherwise detect and be concerned about.”

It sounds like Murnighan is implying that it's a mistake to trust others, and that happy people aren't seeing things clearly. That's an awfully pessimistic assumption.

Moreover, that assumption isn't borne out by the "trust game" itself. In this experiment originated by Joyce Berg, John Dickhaut and Kevin McCabe, two people must make decisions about giving each other money. In the end, the more money they give each other, the more each one ends up with. (But that system only works if each one trusts the other.)