I have mentioned Oxytocin previously and that it was being studied for its effects on social behavior. The earlier studies suggested that Oxytocin might have a beneficial effect in treating conditions such as Autism. This latest PNAS paper is interesting since it suggests that Oxytocin may play a role in group behavior, in this case ethnocentrism. Fortunately, according to the investigators oxytocin appears to enhance the positive aspects of ethnocentrism, ie. “intergroup bias”, versus the negative aspects “out-group derogation”.