Oxytocin love hormone fosters group trust and outsider ethnocentrism

Oxytocin has been described as the hormone of love. This tiny chemical, released from the hypothalamus region of the brain, gives rat mothers the urge to nurse their pups, keeps male prairie voles monogamous and, even more remarkable, makes people trust each other more.

Yes, you knew there had to be a catch. As oxytocin comes into sharper focus, its social radius of action turns out to have definite limits. The love and trust it promotes are not toward the world in general, just toward a person’s in-group. Oxytocin turns out to be the hormone of the clan, not of universal brotherhood. Psychologists trying to specify its role have now concluded it is the agent of ethnocentrism...

Despite the limitation on oxytocin’s social reach, its effect seems to be achieved more through inducing feelings of loyalty to the in-group than by fomenting hatred of the out-group. The Dutch researchers found some evidence that it enhances negative feelings, but this was not conclusive. “Oxytocin creates intergroup bias primarily because it motivates in-group favoritism and because it motivates out-group derogation,” they write.

Plus another little snip on the same research from PhysOrg:

In future research, Dr. De Dreu and colleagues plan to investigate any links between oxytocin and social behaviors that may have evolutionary significance, such as cooperation, penalizing deviation from accepted behaviors, and behaviors associated with religious experience. Dr. De Dreu expects oxytocin will be found to have no more effect on religious experience than other behaviors such as soccer hooliganism, and said that when people join with others who share their values, this “drives up the level of oxytocin.”

[Thanks Sam Hell!]