"Most of the patients know Olive. They don't know me, but they know Olive," says volunteer Mike Azzarello about his Chihuahua mix, with a laugh.
And it's not because they are cute. Studies show petting a dog can decrease stress hormones, regulate breathing, and lower blood pressure. It releases oxytocin, the same hormone that bonds couples after sex and a mother to a child after birth and breast-feeding. Dogs are xenophilic, meaning they love strangers, and unlike humans, their affection comes without expectations and judgment.