How little we know about the neuroscience of fatherhood

Fathers caring for their children is the general rule across most vertebrates; almost all nonmammalian vertebrates use fathers as a prime caregiver.  And yet, the world of neuroscience knows little about paternal care. This is partly because the males of our common laboratory species, the lab mouse and rat, are more likely to eat their young than show any special care for them.  The resulting deficit in knowledge is obvious with any cursory look through a textbook on the neurobiology of parental behavior: after ten chapters detailing maternal behavior, there might be one perfunctory chapter detailing how little we know about paternal behavior.  But here’s a cool fact I learned from one of those chapters: did you know that male Djungarian hamsters assist in delivering pups by tearing away the membranes just after birth.  They play midwife!

It seems like the precise neural circuitry for maternal and paternal care are different; lesioning the amygdala decreases paternal care and increases maternal care.  Likewise, many neurohormones that cause maternal behavior have little effect on males.  But some of these pathways are likely to be the same.  I’ll quickly discuss a paper which describes the influence of the neuropeptides prolactin and oxytocin on paternal care.  Oxytocin is the ‘love hormone’ and strongly stimulates pair-bonding, influences social recognition, and has strong effects on general sociality.  Although it is typically thought of as having a pro-social influence, the reality is a bit more complicated (of course!).  Prolactin is a bit of a sex hormone, providing the body with sexual gratification after intercourse and counteracting the effects of testosterone, estrogen, and dopamine.  It clearly has a stronger social effect as well or I wouldn’t be talking about it in relation to child-rearing!

In order to assess the relationship between these two neuropeptides and fatherhood, Gordon et al. first measured  their concentration in fathers across time and found them to be fairly stable.  When they compared the of these neuropeptides to the propensity of the fathers to play with their children, they found them to be strongly related.  Each were associated with a specific paternal behavior: prolactin with facilitation of a child’s exploratory behavior and oxytocin with how much the fathers matched their facial emotions with that of their children.  Since this is only a correlational study, we cannot say for sure whether or not these neuropeptides are directly causing these behaviors.  However, these are similar to what are seen with maternal behaviors, allowing the researchers to compare their results to the richer maternal literature in the future.  It will be interesting to see if future work can relate receptor variants for these neuropeptides to differences in paternal behavior.  Perhaps we can get a genetics of daddyhood?

Reference

Gordon I, Zagoory-Sharon O, Leckman JF, & Feldman R (2010). Prolactin, Oxytocin, and the development of paternal behavior across the first six months of fatherhood. Hormones and behavior, 58 (3), 513-8 PMID: 20399783

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5 thoughts on “How little we know about the neuroscience of fatherhood

  1. This seems to depend on what the emotion of the father is how well they know the mother or how long they have been together, was the father ready for a child, does the father want a child. All of these would affect the fathers love hormone, which would show how the children and the fathers interact, how much time they could spend together and how the kid will affect the fathers emotions and how he could change the way he sees things. fatherhood will come easy if the father is ready for the idea and is ready to show his emotions and not be “close hearted” which would show that your right about them switching to the role of the “mid wife” and the thing that led to this was the fathers emotions which let him see how much he loves his child and how much he wants to be there for him or her.

    • You’re right that the hormone concentration depends on all sorts of other things – it’s not purely genetic or fixed in any way, but rather responds to the environment, which can certainly be how prepared he is for the child. But the oxytocin behavior I talked about isn’t purely ‘good’ or ‘bad’; I don’t know whether a father matching their facial emotions to that of their child is necessarily ‘good’. It is just one way out of many to bond with a child. And of course how much you do this relates to many other variables, including whether you’re simply in a bad mood! So it’s all very complicated but will hopefully give a little insight into how we decide to interact with our social environment.

  2. We have just discussed the brain and neurotransmitters in my psychology class and I was just surprised by this post. From what I learned about the amygdala in class, it deals with memory, learning, and emotional response patterns. So I guess it makes sense that it can affect maternal/paternal behaviors since mothers and fathers behave different emotionally, but what I don’t understand is how lesioning the amygdala decreases paternal care and increases maternal care. That to me just doesn’t make sense, but I guess a lot of science doesn’t make sense. It also surprised me that some neurohormones that cause maternal behavior have little effects on males. For example, if you give a male estrogen, it’s going to work the same as it does in females. With the two neuropeptides, which are similar to neurotransmitters in how they work, prolactin and oxytocin, I think that the research could possibly get more fathers involved that may not have been involved in the first place. I just think that this post is right in that we don’t know much about paternal care and I think we should find out more.

    • I’ll admit straight off that I don’t know much about development, and I know even less about how the male and female brains differ. I have no idea what is different between male and female amygdala, but it wouldn’t surprise me if, say, testosterone was modulating in one way and estrogen in quite another. That might cause you to see differences in the effects of lesions between males (testosterone) and females (estrogen)?

      Also, neuropeptides that have an effect on females that you don’t see in males almost certainly DO affect males, but they may not effect that behavior that you’re studying. The effects of peptides tend to be pretty complex and often require the interaction of many different peptides, hormones and neurotransmitters in order to have a specific behavioral output. I know in my research, there are neurons that I know have dopamine receptors on them, but dopamine only effects them under specific conditions relating to which neuropeptides are floating around! It certainly makes things more frustrating and confusing.

  3. I found this post really interesting! We are also going over this in my Psychology class- discussing different parts of the brain and nurotransmitters. Its so cool to learn about how different parts of the brain impact parental and maternal care although it doesnt seem to make sense to me. The amygdala is involved in a variety of emotional response patterns, includnig fear, anger and discgust so i guess i can see how that plays into the parental role! But very weird that it also impacts the maternal.. Mothers have a different bond with their children than fathers do

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