O, Oxytocin! Major addition/correction

Oxytocin is the love hormone. It reduces fear and causes feelings of trust. It facilitates birth and breast feeding. Given men oxytocin, and instead of the “flight or fight” response to threat, they go in for tend and defend, a strategy that seems more characteristic of women, according to Sarah Blaffer Hrdy.**

So why in the word does this issue of Science signal an article on oxytocin with a picture of marching troups?

Here’s the abstract and it’s hard to see exactly how war is suppose to fit in.

Science 11 June 2010:
Vol. 328. no. 5984, pp. 1408 – 1411
DOI: 10.1126/science.1189047

The Neuropeptide Oxytocin Regulates Parochial Altruism in Intergroup Conflict Among Humans

Carsten K. W. De Dreu,* Lindred L. Greer, Michel J. J. Handgraaf,Shaul Shalvi, Gerben A. Van Kleef,1 Matthijs Baas,1 Femke S. Ten Velden,1 Eric Van Dijk,2 Sander W. W. Feith3

Humans regulate intergroup conflict through parochial altruism; they self-sacrifice to contribute to in-group welfare and to aggress against competing out-groups. Parochial altruism has distinct survival functions, and the brain may have evolved to sustain and promote in-group cohesion and effectiveness and to ward off threatening out-groups. Here, we have linked oxytocin, a neuropeptide produced in the hypothalamus, to the regulation of intergroup conflict. In three experiments using double-blind placebo-controlled designs, male participants self-administered oxytocin or placebo and made decisions with financial consequences to themselves, their in-group, and a competing out-group. Results showed that oxytocin drives a “tend and defend” response in that it promoted in-group trust and cooperation, and defensive, but not offensive, aggression toward competing out-groups.

The answer, as fas as I can figure out, is that if the out-group gets really threatening, then defending starts to look like agression, and can even result in pre-emptive strikes.

This could give one a whole different view of a certain recent president. Maybe he wasn’t the cowboy lurching out of the salon. He might just have been on a oxytocin high.


**lga reminds us  in comment #6 that the response was originally known as “tend and befriend.” 

Here’s part of an interesting post on it, with an acknowledgement of its discoverer:

Move over “fight-or-flight”–there’s a new paradigm in town, the first new model to describe people’s stress response patterns in more than 60 years.

The model, called “tend-and-befriend” by its developers, won’t replace fight-or-flight. Rather, it adds another dimension to the stress-response arsenal, says University of California, Los Angeles, psychologist Shelley Taylor, PhD, who, along with five colleagues, developed the model.

In particular, they propose that females respond to stressful situations by protecting themselves and their young through nurturing behaviors–the “tend” part of the model–and forming alliances with a larger social group, particularly among women–the “befriend” part of the model. Males, in contrast, show less of a tendency toward tending and befriending, sticking more to the fight-or-flight response, they suggest.

The researchers describe this new model in an upcoming issue of Psychological Review, supporting their premise by pulling together existing evidence from research with nonhuman animals, neuroendocrine studies and human-based social psychology.

The tend-and-befriend model fills what Taylor sees as a huge gap in the stress response literature: namely, that almost all the studies have been conducted in males and so, therefore, upheld fight-or-flight as the main response to stress.

The tend-and-befriend response, in contrast, fits better the way females respond to stress. It builds on the brain’s attachment/caregiving system, which counteracts the metabolic activity associated with the traditional fight-or-flight stress response–increased heart rate, blood pressure and cortisol levels–and leads to nurturing and affiliative behavior.


What stimulates this behavior in the mother? Taylor and her colleagues suggest that it’s governed in part by oxytocin. Studies in many different animals, including non-human primates and humans, show that oxytocin promotes caregiving behavior and underlies attachment between mothers and their infants. In addition, some studies have found that mothers tend to be more nurturing and caring toward their children when they are most stressed.

…  Again, oxytocin may be at play, they suggest. In female prairie voles, for example, injections of oxytocin enhance social contact and inhibit aggression. The same may occur in males, but males are less likely than females to have naturally high levels of oxytocin…

Although the tend-and-befriend model emphasizes gender differences, the researchers reject the idea that gender stereotypes are written in our genes. Indeed, Taylor doesn’t see biological models of behavior as inherently constraining–rather, they help tie human behavior to other species and provide a framework for general behavioral tendencies. The fun, she says, will be teasing apart how our biological predispositions unfold in the context of real-life experience.

Adds Taylor: Mainstream stress researchers “have been very quick to study behaviors like aggression and withdrawal and have failed to notice very important behaviors like affiliation. We think it’s cute when women call up their sisters when they’re under stress. But no one has realized that that is a contemporaneous manifestation of one of the oldest biological systems. Our focus on fight-or-flight has kept us from recognizing that there are systems that are as old as fight-or-flight that are tremendously important.”