A man walks down the street with his wife, who is pregnant with the couple’s first child.
With no kids, he has existed until now in his own orbit and paid little attention to the offspring of others. He notices a woman with a baby and the moment causes him some consternation — he feels very little for the child and worries that perhaps he lacks the empathy to be a dad. Are certain men, he wonders, hardwired to respond better to infants than others?
Pregnancy and parenting research has disproportionally favoured mothers, for obvious reasons, but there is a growing scientific interest in what happens in the brains and bodies of men who become fathers.
Pilyoung Kim, head of the Family and Child Neuroscience Lab at the University of Denver, is one of the researchers looking into this area. Based on experience with her own husband, Kim wondered about the biological changes that signal fatherhood, or to put it more bluntly, how a man can go from zero interest in children to putting them at the centre of his life. The question that guided her research: Can fatherhood change the male mind?
Working with a team, Kim examined 16 biological fathers, taking MRIs two to four weeks after their child was born, and again about 10 weeks later. The results suggest there is a physical shift.
“In studying fathers with their new babies, we found out that a man’s brain actually does change—it gets rewired to support the evolutionary role of becoming a parent,” says Kim, who released her data in a 2014 paper entitled “Neural Plasticity in Fathers of Human Infants” in the journal Social Neuroscience. “The brain regions involved in parenting, providing warmth and care of an infant, showed anatomical growth in men from the first month postpartum.”
“Gray matter increased in the hypothalamus, the area responsible for sensitivity, while simultaneously decreasing in the orbital frontal cortex—which looks after stress regulation and cognitive processing,” says Kim, who points out that behaviours such as affectionate touch, loving presence and even a new parent’s dewy gaze are all rooted in specific neurologic regions.
Imaging also revealed growth in the lateral frontal cortex, a new finding. “This growth had never been reported in men before and is quite remarkable — it’s the part of the brain motivating fathers to feel an emotional connection with their baby,” she says. “In essence, the brains of new fathers had become hardwired to respond when they hear their babies’ cries.”
Parenting instincts are often assumed to be innate, or disproportionately under the dominion of the mother, but the truth is neither parent is born with the neural structure for the role — their brains evolve for the function. And the brain isn’t shape-shifting in isolation. Researchers have a term for when neurological changes alter behaviour while the new behaviour simultaneously alters the brain — it’s called “bi-directional,” and makes sense. As our environment changes us, we change our environment.
The time is right for research into dads. The family structure has evolved over past 50 years, with fathers increasingly sharing the parenting load. We now know that a father’s engagement with an infant is important for optimal child development and, society is reflecting an egalitarian shift, with 25 per cent of Canadian dads taking parental leave (80 per cent in Quebec, which offers five weeks paid time off).
Michael Lamb is head of the department of social and developmental psychology at the University of Cambridge, and editor of The Role of the Father in Child Development, a guidebook that teaches psychotherapists how to apply the latest scientific research in the treatment of fathers. I asked him to reverse that thinking and talk about the role of children in developing fathers.
“The important thing is that your baby is nothing like the baby that you might see on the train,” says Lamb. “When it’s your child, your baby, it’s a transforming experience.
“Once you’re a dad, you can be a lousy dad, walk out on your children, fail to deliver for them, but from that point on, you’re a father,” he continues. “For social, psychological and even biological issues, from the moment of birth onwards, just like for the mother, the father can’t go back again — a man’s very systems have changed.” Here he’s referencing the work of Lee Gettler, whose research, published four years ago in Proceedings of the National Academy of Sciences, was the first to show that mens’ testosterone levels fall when they become fathers. The work, done as part of a longitudinal study at Northwestern University found a 26% drop in morning testosterone levels and 34% drop in evening levels among new fathers, compared with 12% and 14% — attributed naturally to age — for their peers without children. According to Gettler, when men experience such a rapid decline in testosterone, it alters the way they behave.
Your baby is nothing like the baby that you might see on the train.
“Men with high levels of testosterone show tendencies toward anger, risk-tasking and low empathy, all of which could negatively impact the sensitivity of and warmth of dad’s parenting,” says Gettler.
His research further suggests that when fathers increase their level of parenting involvement, testosterone levels continue to decline. “These declines in testosterone in new dads are in the range where we would expect it to have some effects on their behaviour,” says Gettler. “We predict that such changes in dads’ testosterone would lead to more commitment to parenting and partnering and more sensitivity when they’re caring for their kids.”
It’s impossible to know how you will feel for your kids before having them because the very nature of your child’s birth — for both men and women — alters who we are. Building a relationship, however, takes time.
“It doesn’t just happen because some magical switch gets pulled in the cosmos. Changes in a man occur after their child is born based on how much proximity we want to have with our children,” says Walter Gilliam, director of the Edward Zigler Center in Child Development and Social Policy at the Yale School of Medicine, and father of a 16-year-old girl. “As the father makes more overtures to the child, the child makes more overtures to the dad — it’s a two-way street.”
In discussing what happens to a man when he becomes a father, Gilliam tells an old psychiatry joke:
Q) How many psychologists does it take to change a light bulb?
A) One, but the light bulb has to want to change.
“When men care deeply about their partner or children, and spend more time in their company, the brain becomes adapted to seeking out their company even more, thinking about them when you are away, and wanting to protect and care for them,” Gilliam says. “Absence does not make the heart grow fonder. Closeness makes the brain grow more connected.”
Pilyoung Kim’s husband Tom was never the type of man to make a big deal out of a coworker bringing their new baby to work. That all changed the moment his son Lucas was born.
“Now I don’t mind sitting near them when I go on a plane. In fact, I even kind of like it,” he says. “It’s crazy. I used to notice sports cars, now I notice strollers. I guess you can call that a pretty big change.”