The challenges of parenting may build cognitive reserve Craig Boylan
When you are pregnant, everything changes. Hormones surge, your belly swells, cravings kick in. Until recently, the story was assumed to end there – that once the physiological and hormonal upheaval of pregnancy and birth resolves, the body and mind largely return to a pre-pregnancy state. It is clear now that this isn’t true.
During pregnancy, another transformation unfolds. Inside the skull, the brain quietly remodels itself in ways that shape a mother’s ability to care for her child. Far from being temporary, many of these changes persist for years – perhaps even a lifetime. This phenomenon isn’t restricted to the person who gives birth, either. Fathers’ brains also experience changes during the transition to parenthood. “Few brain regions go untouched,” says , a professor of neuroscience at the University of California, Santa Barbara.
Scientific consensus about the parental brain has undergone a profound shift in the past decade. What was once dismissed as “mum brain” – a forgetful, sleep-deprived state offset by an almost superhero-like vigilance for your child – is now understood as something more complex: a combination of highly orchestrated neurological adaptations that may influence everything from empathy and attention to memory and even ’s risk.
From the earliest stages of pregnancy, grey matter – the brain tissue packed with neuronal connections – begins to change. In many regions, it shrinks as connections are pruned. Researchers stress that this isn’t a sign of damage, but of fine-tuning. “Think of Michelangelo’s David, where the underlying beauty is revealed through the art of removal,” says Jacobs.
A series of studies – including one in which Jacobs and her colleagues – show that the most striking transformations occur within the default mode network, a system involved in self-reflection, planning, and emotional and social cognition.
Free newsletter
Sign up to Eight Weeks to a ҹ1000ier You
Your science-backed guide to the easy habits that will help you sleep well, stress less, eat smarter and age better.
These changes are linked with how easily a mother connects with her baby and how strongly she – the greater the changes, the greater the bond. “The brain is becoming more specialised, rather than impaired,” says , a psychologist at City University of New York. “[It] appears to prioritise information that is relevant to caregiving, threat detection, emotional interpretation and rapid environmental monitoring.” New mums will recognise this phenomenon – while they may forget where they placed their keys, they are remarkably attuned to subtle changes in their baby’s breathing or demeanour.
Jacobs and her colleagues are now studying the brains of other first- and second-time mums, alongside fathers and those who have never been pregnant. In unpublished work, they found that 97 per cent of the 400 brain regions examined changed significantly during a first pregnancy. Second-time mums, meanwhile, showed less dramatic shifts, having only partially rebounded in the postpartum period.
These discoveries are updating the way we think about the transition to motherhood, says Jacobs. “It’s dispelling outdated notions of ‘mummy brain’ as being dysfunctional ǰinadequate, and instead portraying the maternal brain as one capable of continual adaptation.”
Other evidence indicates that parenthood alters fathers’ brains, too. Like mothers, they experience of a child. These changes are also , such as resourcefulness and affectionate touch. In fact, the more time spent directly caring for children, the more fathers’ brain activity resembles that seen in pregnant women and new mothers.
Parenthood also seems to change fathers’ brains GFC Collection/Alamy
It is important to note that most of these studies included only heterosexual couples or didn’t ask people about their gender identity or sexuality. So it is unclear whether same-sex couples or non-binary individuals experience the same brain changes.
It is also unclear how long these changes last. But evidence suggests they endure. A study in 2021 showed that pregnancy-related reductions in grey matter were still present . In another study, neuroscientist at the Ann S. Bowers Women’s Brain ҹ1000 Initiative in California and her colleagues showed that several brain regions remodelled in pregnancy and early parenthood , indicating some changes may last a lifetime.
The parental brain also seems to come with durable improvements in cognition. Compared with women without children, mothers have superior attention and “executive functioning” for at least . Executive function acts as the brain’s air traffic control system – it enables us to solve problems, switch between tasks and prioritise important information while tuning out distractions. This may come as little surprise to anyone who has watched a parent simultaneously cook dinner, stop a child from scribbling on the wall and locate a missing shoe without a pause.
A buffer against ageing
The very challenges of parenting may benefit brain health in later life by building “cognitive reserve” – the brain’s resilience to damage, illness or cognitive decline.
The idea is rooted in the blunt fact that parenting is hard. It involves taking on more responsibilities, learning a constant stream of novel skills and juggling multiple priorities alongside existing responsibilities. Add in sleep deprivation and limited resources, and parenting equates to a formidable cognitive challenge.
Over time, this sustained mental workout may act much like learning a second language ǰplaying a musical instrument – building larger, more flexible and efficient neural networks that help ward off dementia.
Demonstrating this in humans is difficult, however, because factors such as genetics, socioeconomic status, diet and other lifestyle choices intersect with parenthood to influence brain health.
That said, intriguing patterns have emerged. For instance, in the only study of late-life maternal brain activity, Orchard and her colleagues compared patterns of brain activity among adults in their 70s with models of age-related decline. They found that mothers with more children . Orchard suggests the results are the first indication that .
Parenting is like a sustained workout for the brain plainpicture/Lassalle, Bénédicte
Similarly, a 2025 study of nearly 28,000 people, which Orchard also led, found that both mothers and fathers in mid- to late-life than those without children. Given the effect is seen across sexes, it suggests that parenthood, not just pregnancy, shapes the brain, potentially for the better.
While there are nuances to consider – genetics might make someone more fertile and more likely to experience brain changes, for instance – it does raise the intriguing possibility that parenthood helps buffer brains against conditions like ’s.
Most research points to a U-shaped relationship between the number of children you have and dementia risk, says , a sociologist at the University of Alabama at Birmingham. The greatest risks are associated with having no children or having lots, typically four or more. But other studies show conflicting results.
The inconsistencies come partly from differences in how cognitive decline is defined and the types of populations studied, says Thomeer. When she carried out a study attempting to control for these factors, many of the associations disappeared. “In other words, it seems that there are multiple childhood and adolescent factors that impact both whether a person has children and how many children they have, as well as their later-life cognition.”
The picture may also be changing across generations. In a second study presented at a cognitive ageing conference at Vanderbilt University in Tennessee in May, Thomeer and her colleagues showed that in more recent birth cohorts, having no children is increasingly associated with better cognitive health in later life.
Thomeer suggests that this trend may reflect changing socioeconomic factors. For instance, child-free women are now more likely to be highly educated than in the past. It could also indicate unique stressors of modern parenting.
Parenting may influence the ageing brain through biology as well. Fetal cells cross the placenta and embed themselves in the mother’s organs, including her brain, a phenomenon called microchimerism. Here, they appear capable of turning into neurons and immune cells, raising the possibility that they may play a role in brain repair. A 2012 study found women with ’s disease have than women without the condition, hinting that the cells offer some protection.
So, the quest to understand the parental brain continues. Having children running around the house is no guaranteed defence against dementia, nor is it a temporary biological event that leaves us untouched. It boosts our empathy, multitasking skills and perhaps even our cognitive reserve. Whether that wards off cognitive decline in our later years remains to be seen. One thing is clear: children don’t just leave a lasting imprint on our homes, routines and sleep. They leave an indelible mark on the brain itself.
This article is part of a series on brain transformations:
The surprising ways your brain changes from your 20s to your 40s
How some people’s brains make an extraordinary recovery from stroke
How menopause radically changes the brain – and what happens after
Our brains have their first thoughts unexpectedly early in life
Why you need to future-proof your brain in middle age and how to start
What is a ‘normal’ memory slowdown, and when should I worry?
The secrets to keeping your brain sharp in old age
Topics:
