Research: Breast-Feeding Moms are Overly Aggressive in Games, Life

According to a study that will be printed in the September issue of Psychological Science, breast-feeding moms are more aggressive than moms who use formula. You may be wondering why a study about breast feeding moms might matter to you, and the reason it does is because of what researchers used to test these aggression levels. The researchers' hypothesis was that mothers display a higher level of aggressiveness while breast feeding. This theory is rooted in previous research in non-human mammals that shows that lactation seems to trigger heightened defensive aggression because it apparently decreases an animal's fear response.

To test this theory researchers found 18 mothers who were nursing their children, 17 who were using formula, and 20 women who did not have kids. All of the participants were asked to play a video game against a research assistant who pretended to be an overly aggressive and competitive player. When a participant won a round of the competition, she was allowed to press a button that delivered a "punitive sound burst" to their opponent.

When all was said and done, researchers found that the breast-feeding mothers inflicted the loudest and longest punitive sound bursts on the research assistant than the other two groups. Mothers who breast-fed their infants were almost twice as aggressive as formula-feeding women and non-mothers, according to researchers. Formula-using moms and non-mothers were equal in their levels of aggression – which wasn't all that high, apparently. Oddly enough, researchers also found that while breast-feeding moms were highly aggressive as they played and won their compeititos, their blood pressure remained normal.

"Breast-feeding mothers aren't going to go out and get into bar fights," said UCLA's Dr. Jennifer Hahn-Holebrook, lead author of the study. "But if someone is threatening them or their infant, our research suggests they may be more likely to defend themselves in an aggressive manner."

The Hahn-Holebrook research, "Maternal Defense: Breast Feeding Increases Aggression by Reducing Stress" can be found in the September issue of Psychological Science. More details can be found here.

Source: io9


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  1. 0
    kurifu says:

    The field of psychology is one where they often fail to or neglect to prove causality, in fact much of the field, from the public perspective, doesn't care to show causality as it does simply trying to show correlation. I think the issue here is simply the nature of there work and until biology gives us a much clearer understanding of the brain this situation will remain.

    ANY field whose goal is correlation over causality is not a real science; that is all this study, and many others like it, will ever hope to prove. There is no way to reasonably show causality for the complex human behaviors by simply assessing environment.

    This doesn't mean that psychology has no place or value, I just think too many people, mostly psychologists, have long forgotten what that means.

  2. 0
    axiomatic says:

    There might be "science" going on here but the scientists have clearly misunderstood the cause. The knowledge that a pregnant woman with a HEAVY kid in her uterus, straining her back and bladder, is more easily annoyed/aggravated by a loud noise should be obvious to anyone (ESPECIALLY men) who has ever been physically/verbally accosted by a pregnant woman just for getting in their way.

    If there was ever a need for the axiom "causation does not equal correlation" this would be it.

  3. 0
    Chris Kimberley says:

    My understanding also.

    I can't say I'm surprised at the findings though.  Mother's are known to be fiercely protective of their young.  It makes sense that the hormones associated with breastfeeding would increase aggression.

  4. 0
    Neeneko says:

    Since when is psychology not considered a 'real' science?

    It is one of the more difficult and complex ones, but you can still apply the same scientific method to psychology as you can to other fields.

  5. 0
    kurifu says:

    I thought psychology wasn't considered a real science?

    Seriously… stop trying to prove this ridiculously specific causalities with a "science" who's sole purpose is a first order high level approximation of complex topics like human behaviour.

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