A mother’s impulse to love and protect her child appears to be hard-wired into her brain, a new imaging study shows.
The maternal instinct may be connected to brain circuitry, a new study suggests. (Francesco Tonelli for The New York Times)Tokyo researchers used functional magnetic resonance imaging (M.R.I.) to study the brain patterns of 13 mothers, each of whom had an infant about 16 months old.
First, the scientists videotaped the babies smiling at their mothers during playtime. Then the women left the room, and the infants were videotaped crying and reaching for their mothers to come back. All of the babies were dressed in the same blue shirt for the video shoot.
M.R.I. scans were taken as each mother watched videos of the babies, including her own, with the sound off. When a woman saw images of her own child smiling or upset, her brain patterns were markedly different than when she watched the other children. There was a particularly pronounced change in brain activity when a mother was shown images of her child in distress.
The scans suggest that particular circuits in the brain are activated when a mother distinguishes the smiles and cries of her own baby from those of other infants. The fact that a woman responds more strongly to a child’s crying than to smiling seems “to be biologically meaningful in terms of adaptation to specific demands associated with successful infant care,” the study authors noted.
“This type of knowledge provides the beginnings of a scientific understanding of human maternal behavior,” said Dr. John H. Krystal, in a press release. Dr. Krystal is the editor of Biological Psychiatry, which published the study last month. “This knowledge could be helpful some day in developing treatments for the many problems and diseases that may adversely affect the mother-infant relationship.”
Because the study only looked at mothers, it’s not known whether fathers have similar brain responses to a child’s smile or tears.
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From 1 to 25 of 115 Comments
This does seem to be proving the bleeding obvious. If babies and mothers can distinguish each other by smell from birth (see http://preview.tinyurl.com/2cr545 ) then identifying the parts of the brain involved is just the next step not the big breakthrough.
What happens then to mothers who are shown NOT to have these “natural” responses in their brains to their infants? Will they be locked up as freaks or have their kids taken from them? I can just imagine.
Or will neglectful mothers be able to say “oh its biological, I can’t help not bonding with my child”?
I applaud further research into all aspects of the human brain but you and other non-scientist commentators are vital in directing HOW this is viewed. It would be nice for your blog to put it in some more context.
Also, extending this kind of research - how does a mother’s ability to interpret the infant’s cries (not just identify they are from her own infant) look in the brain? And what of those of us who never master this. I’ve read Priscilla Dunstan http://www.dunstanbaby.com/ and I have to say I could never hear the difference between my babies’ cries. I was just grateful when they could talk and be more communicative. So once they find some biological basis for that “skill” Dunstan promotes, I’ll be told what a bad mother I was.
Where’s the good in that?
— PlainJaneAt 16 months these babies would have had their own “language”…each baby’s babble sounds a little different. It would be interesting to know how well this experiment works with much younger babies whose vocalising is not as differentiated.
Also the really funny evolutionary spin on this is that mothers’ brains reacted more strongly to distress. I knew when I saw my son’s new manipulative tantrums that he was onto something. He knows I can’t stand to see him cry!
Seems to me the babies are ahead of the game here!
— JillyFlowerFrom TPP — Some studies have looked at mothers’ reactions to infant crying, but in the study there was no sound on the videos.
This *is* a big duh, but not all mothers will react to those brain patterns in the same way. And poster #1 is correct. What about those whose brain patterns don’t replicate the ‘norm?’
— VanessaWill they also do a test on fathers?
— KatieBy 16 months mothers and children must be bonded, and of course the mothers would react to seeing their child in distress - for more than a year they have been reacting to their child to meet its needs. I would be curious to see the difference in brain waves of mothers who had just given birth versus those who have nurtured their babies already for some time. To me a comparison of brain waves before and after giving birth would better show maternal instinct was “wired”. And what about moms who adopt? or use surragates?
I would never have suspected that mothers have a special attachment to their own children. What will they find out next?
— MarkThe phrasing is misleading and suggests a common but fundamental misrepresentation of what this type of fMRI research shows — or maybe a misunderstanding that confuses a general audience. “Wired,” “hard-wired,” and “instinct” suggests genetically programmed in, like a reflex. A brain pattern that shows up on fMRI studies, however, can reflect brain “programming” that has been acquired through experience, to use the computer metaphor.
— MarcusI can’t help but feel like this research is going to be used as the crux of some defense lawyer’s argument as to why his client abandoned her child. While I’m sympathetic to post-partum issues (it took me longer than expected to bond with my son after birth) I was still fiercely protective of him and responded to him, although I was terrified of not doing it right when I went to him. I think the mother-infant bond is more complex and this is just one of the many layers of the proverbial onion.
— LJBWhy would they not do the experiment on fathers as part of the same study? It seems the father-infant relationship is just as important, unless of course childcare and psychological rearing is regarded as more the mother’s responsibility. (I’m sure no one assumes that!)
— SloanWhy didn’t the researchers include an equal number of fathers in this first study? Would it have been so difficult? Or would that have undermined the agenda of providing biological evidence as to why women are and should be the primary caretakers?
— Why?Will you please stop turning us into machines?
— jiminboulderAbsolutely remarkable!! Who knows? Maybe certain areas of the brain light up when you get hungry. What’s even more amazing is that someone may have funded this dribble.
— RR“The scans suggest that particular circuits in the brain are activated when a mother [looks at her own child].”
Certainly the study has more complexity than the author has summarized here. Is this an insufficient review or a ridiculous study? There’s no way to know.
— Beck ChildsThe absolute hilarity of the line “This type of knowledge provides the beginnings of a scientific understanding of human maternal behavior,” made my day!
Jeanne, mother of five
— Jeanne Galatzer-LevyAre you kidding? We spent money to learn this?
— DanielleWow. Mothers responded differently to their own 16-month old child, even though it was dressed in the EXACT SAME SHIRT as all the other infants? This is truly a scientific breakthrough, not only for biologists but for clothing manufacturers worldwide.
— Snead HearnI’m surprised to see such a weak study (at least if it’s been accurately described) get mentioned in the Times.
If I watched someone’s nice race bike get run over by a car or stolen, I’m sure there will be some brain activity showing my reaction. If I watched my OWN custom bike get crushed or stolen, my brain waves would be off the charts. Is my desire to protect my “baby” hard-wired?
Is the argument that adoptive parents don’t feel the same “hard-wired” attachment?
I don’t doubt that there is some sort of hormonally-mediated “bonding” that occurs even in the first hours after childbirth (and maybe long before), but my guess is that if babies were switched in the hospital (obviously you can’t run an experiment like this) that the mothers would promptly show the same response for babies that aren’t biologically their own. So what exactly has this study proved?
Just because you can measure brain-wave activity doesn’t prove very much and certainly not that anything is “hard-wired.”
— MariaBreastfeeding helps strengthen this bond straight from day 1. The list of miraculous things it does goes on and on. Why do relatively few people ignore this?
http://www.babymilkaction.org
— JunebugVery interesting research but Parker-Pope unfortunately will become an example in future classes of mine, of journalists who make inferences way beyond the data. She also happens to do it in a way that conveniently seems to support a common gender stereotype.
The data say nothing at all about “maternal instinct”. The brain patterns say something about people who have formed an attachment with a baby for whom they had provided care for 16 months. We need brain scans of men who have given comparable care to their babies, and of people who have given comparable care to babies that they did not provide genetic material to.
It well may be that anyone who cares for a helpless infant from birth to 16 months will show similar brain patterns.
From TPP — that’s what i made the point that fathers hadn’t been studied. It would be interesting to know if there are differences in men’s brains as well in responding to their own children.
— NancyDon’t we often discuss a maternal instinct that extends to other babies, other animals, other living things? I might have expected to see similar activity in a mother viewing images of a distressed baby even if the baby was not hers.
— adrianeFROM TPP — I found that interesting too. I know personally, i see a child hurt or crying I react to it, so it surprised me that there was such a difference in how the brains reacted to an unknown child vs. one’s own child.
I agree with PlainJane. The fact that we have neural circuits in the brain that are wired for social interactions is not new. Nor is the idea that learning changes neural responses. Perhaps I missed something, but how is this surprising.. that neural circuitry of mothers is selective for their own children? What’s the follow-up article… Young children are hard wired to respond to parents… until adolescence!
— Bob McGivernThe article uses the term “hard wired” to describe the reaction of the mothers to their own infants behavior. If we were talking about animals the term used would be “Instinctual.” In fact the process is the same and what it shows is that we are all descended from the same source. Now we can argue about what that source is, but the connection is inescapable. PlainJane is too worried about idiosyncratic departures from the norm to see the value of this research. Once we know the genetic basis of an action we can try to correct problems that arise from idiopathic departures from normality.
— Joel FriedlanderA 16 month old is hardly an infant. Most are walking, babbling, laughing, little personalities. As the non-biological caregiver of a 16 month old girl I love, I’m confidant my brain waves would light up if I saw she was crying - I’d want to run back in the room to comfort her, knowing my presence would soothe her immediately. There’s no urgency to intervene with a content loved one - she’s happy, so you’re happy. Seeing your baby smile (and by “your” I mean any baby you love) is a natural endorphin rush. Seeing your baby crying for you would probably stimulate a flood of cortisol or adrenaline. Of course a mom would react differently to a stranger’s child. If moms didn’t personalize their protective impulses there would be little need for charities to plead with Americans to help feed the malnourished, impoverished, innocent and beautiful children “for as little as a nickel a day.” This article would be more compelling if the infants were 16 days old - not 16 months. I think there should be a study done on the researchers who found these results surprising.
— Lorraine Szyp.Unfortunately, this sounds like another poorly done brain imaging study that gets far more attention in the popular press than it warrants. How are we to know that these brain regions showing own-baby-specific activity aren’t simply responding to familiarity, in the same way they might become active in response to pictures of the car or house or cat I’ve had for 16 months? After all, mothers with 16 month old babies have presumably spent an awful lot more time looking at their own babies than at other random babies.
Also, there is absolutely no basis to interpret any of the results in this study as pointing to something about maternal love that is “hard-wired.” Usually, we interpret “hard-wired” to mean that things are innate, not learned. But these mothers have had 16 months to LEARN to respond to their babies. Furthermore, I’m not at all sure you wouldn’t find these results differing at all if you showed women pictures of their own pets in distress versus other pets in distress.
Given the intensity of of beliefs in this country about how women ought to respond to the idea and acts of mothering a child, and how caught up we are in anything brain imaging related, it’s a bit irresponsible to go interpreting a scientifically sketchy study as evidence that maternal love is hardwired. Please be a little more responsible in the future - seek out the skeptical comments that you should be able to find in just about any respectable neuroimaging lab.
— BrieWhat a stupid piece of science.
Study missing one obvious control. Would mothers respond the same way to babies that they have spent an equal amount of time with? It’s nothing hard-wired — it’s only an additional emotional response that comes with familiarity.
— ScientistSo when we think something, there’s activity in the brain. Stunning.
— Andy T