Neuroscientist Dr Jodi Pawluski: “When it comes to the maternal brain, less is more.”

The Tinto expert discusses the positive effects of motherhood on the brain, and the science behind the baby brain memes.

6 min readFeb 25, 2021

“We need to conceptualise mummy brain differently,” says Dr Jodi Pawluski. “It’s not just about putting your keys in the fridge or forgetting the word for this or that. It’s a whole series of amazing changes that happen so that you can take care of your child.”

Mum brain, also known as pregnancy brain or baby brain, usually refers to the forgetfulness or mental fogginess that many women report during pregnancy or in the postpartum period. The anecdotal evidence of mum brain is exceptionally easy to stumble across, circulating through memes in online mum communities.

A quick search brings you to countless examples of mum brain, including “I put the kettle in the fridge instead of milk,” “when you talk to someone on the phone… while hunting for your phone,” and “I just tried to zoom in on my paperback book as if it was my tablet.” Gaining countless likes and comments, these kinds of posts are certainly relatable and at first glance seem harmless. But are they also reinforcing an over-simplified version of baby brain? One that, as a popular meme puts it, propounds the idea that “we used to have functioning brain cells, but we traded them in for children”?

Dr Jodi Pawluski certainly thinks so, arguing we need to rethink mum brain. And with a BSc in biopsychology, a MA in psychology, a PhD in neuroscience and a podcast called Mommy Brain Revisited behind her, she would know. For the past 15 years, Dr Pawluski has worked with rat mothers, investigating brain changes during pregnancy as well as how medications — particularly antidepressants — impact those brain changes.

Dr Jodi Pawluski

There’s not a switch that turns on in your brain when you have a baby. You have to learn things. For biological mothers, physiological changes prime them to learn quickly.

Certainly, pregnancy has huge impacts on the brain. But memory loss? The research is patchy at best. “The first real study looking into ‘mummy brain’ was a survey done in the 1980s by a team of researchers from the UK. They simply asked women if they felt they had memory changes, fogginess or confusion during late pregnancy or the postpartum period. About 80% of women said they had but of course, this is subjective. Objective tests were not given to verify these results at the time.”

Although a little more research has been done since, we still don’t know exactly what is going on with memory in the maternal brain. The best we have is the 2017 study headed by Dr Elseline Hoekzema from the Institute of Psychology at Leiden University. Hoekzema looked at participants’ brains before they were pregnant, right after they’d given birth and then two years later. The findings are staggering: the changes found in the maternal brain during pregnancy are as big as those seen during adolescence. In fact, these changes are so consistent that it is actually possible to tell if a woman has recently had a baby through a brain scan.

The headline might be impressive but, according to Dr Pawluski, it’s the substance of the study that has been taken out of context by both traditional and social media. Hoekzema concluded that many brain areas saw a reduction in volume during pregnancy. “This often leads mums to think, ‘oh, so my brain is smaller and that’s why I’m forgetting everything’”, Pawluski tells me. “But in fact, this study did not show any changes in memory. Instead, the decrease in size was associated with brain areas that are important for social behaviours. And the reduction actually led to greater feelings of attachment to the mothers’ new-born.”

In other words, there’s a lot more to mum brain than the losing of brain cells. “Smaller size may just mean more efficient use of existing synapses,” Pawluski explains. “The brain is fine-tuning so that new mums can learn very quickly how to take care of their babies.”

Indeed, Dr Pawluski’s own research shows that, in the brains of rats who have just given birth, there is a decrease in the production of neurons in the hippocampus — an area of the brain important for memory. But, despite this decrease in neurogenesis, the rat mums actually perform better in memory tasks three weeks after giving birth than those that didn’t have offspring. So perhaps, when it comes to the maternal brain, less is more.

Mum brain research in animal models. Here you can see brain sections of a mother rat before they are mounted on a slide for analysis. Courtesy of Dr. Jodi Pawluski.

“We don’t know enough when it comes to ‘mummy brain’,” Pawluski points out. “What I would love to see is research where a memory task with specific baby elements is used. I want to know if a mum would have better memory for things important for her baby compared to more generic non-baby related things like remembering where she put her keys that morning. If we were to look more closely at specific types of memories, I would guess that most mums would remember the things relating to their child quite well.”

For most women, baby brain is at least a little funny and, at most, a little inconvenient. “But,” Pawluski is keen to remind us, “for some women it is very significant. If you’re feeling very forgetful or foggy and it’s repeatedly interfering with your daily functioning and emotions, definitely seek support.”

Indeed, recent research suggests a link between women who experience severe memory deficits and women who suffer from depression or anxiety. Changes in sleep and mood are very likely to impact memory function — two things that the vast majority of new mums will experience. Separating out the impacts of sleep and mood from brain changes can be tricky. “Some of the best studies,” Pawluski explains, “have tracked women before they get pregnant, through pregnancy and then in the postpartum period. That way you can ask them about their sleep, mood and stress, and then statistically account for that.”

For Pawluski, it’s all about getting more specific when we talk about baby brain. But simultaneously, as Pawluski points out, our language must become broader and more inclusive too.

One study by Winnie Orchard, a PhD candidate, looked at the brains of parents in their 70s and showed that it is still possible to see the effects of parental brain many years later. This is fascinating but, as with all good research, Orchard’s work throws up more questions for Pawluski than it answers. “How is the parental brain affected by your relationship with your adult children? What about whether you’re a grandparent? What happens to the brain after the death of a child? Or if you give your baby to someone to adopt, or if you have adopted a child?”

Simply put: how much does so-called “mummy brain” depend on you being a biological mother? “We just don’t have the research yet,” Pawluski tells me. “But, from the little we do have, it seems that if you’re the primary carer of a child then your brain will change for a lifetime. If you are not the biological mother, these changes might take place more slowly — but they will come.”

“After all,” Dr Pawluski grins, “No one gives birth knowing what they’re doing anyway. There’s not a switch that turns on in your brain when you have a baby. You have to learn things. For biological mothers, physiological changes prime them to learn quickly. But the parental brain isn’t unique to mothers. And with time and persistence and motivation and drive and love, you can parent.” And, well, if that shouldn’t become an overused quote on the internet, I don’t know what should.