Shy people's willingness to interact with strangers depends heavily on their mood, suggests a study led by Christina M. Brown, an assistant professor of psychology at Saint Louis University in St. Louis. When volunteers were asked to place their chair near the chair of a conversation partner who was said to be coming, shy people in neutral moods sat closer than shy participants in happy moods. More sociable types who felt happy sat closest, but when feeling neutral, outgoing and shy people sat similarly. Introverts keep their distance when they're cheerful so that their mood won't be thwarted by social discomfort, Brown theorizes. She advises shy people to focus on the benefits of socializing—an interesting chat, a new friend—rather than the risks.