Women’s Brain: the Neuroscience of Better Health | Jim Kwik & Dr. Sarah McKay

I sort of had an aha moment. I thought, I've spent all of these years working as a neuroscientist. I've been the owner and operator of a female body and brain my whole life, and I've never really considered how the two come together.

Dr. Sarah Mackay, she's a speaker. She's also the founder of Think Brain and the Neuroscience Academy suite of training programs.

We have this real tendency, especially when we talk about women's health, to blame the hormones when things go wrong. Or to blame our biology or to blame our genes. But we know an infant needs a loving caregiver. We know teenagers need to feel like they belong to a tribe. We know new parents need social support networks around them more than anything. And that's a stronger determinant of the experiences we have than anything.

Welcome back to the Kwik Brain Podcast. I am your host and your brain coach, Jim Kwik of Kwik Learning, where we help people to learn quickly. And today we are going to talk about the complexities of the human brain that enables us as male, females to foster better communication and ultimately thrive in relationships and our own performance. And so this is an episode you don't want to miss. I encourage you to really focus on this one. We're going to go a little bit into the brain. And so I encourage you to take notes. That always helps with the forgetting curve. We have a very special guest on with us today, a neuroscientist, Dr. Sarah McKay. She's a speaker. She's also the founder of Think Brain and the Neuroscience Academy suite of training programs. Sarah is the author of what we're going to talk about today, The Women's Brain book. This is the neuroscience of health, hormones, and happiness. She also has a second book called Baby Brain, which we're going to talk about in another episode, really the surprising neuroscience of how pregnancy and and motherhood sculpt our brains and change our minds for the better. And so, Sarah, thanks for being on our show.

Oh, thank you for the invitation. I'm delighted.

Yeah, this is a long time coming. I know we wanted to do this for a minute. You know, when we're talking about the complexities of the human brain, before we get started in this, can I ask you what sparked your interest in women's brain health and neurobiology?

Oh, good question. I've been a neuroscientist. I started my undergraduate degree back in 1996. which ages me significantly, but it's my 30-year anniversary of being a neuroscientist. I never considered women's health through the lens of neuroscience until around 2016. And I used to say that that was because neuroscience is such a big, deep, complex, rich subject, which it is, and that I was just too busy studying all of the intricacies of brain plasticity, brain development, et cetera. But truth be told, Women's brain health, the kind of, this sort of new shift, this focus towards thinking about aspects of the female brain through the lifespan, what happens during puberty, pregnancy, menopause, the menstrual cycle, the oral contraceptive pill, we've only started to see that research emerge in the last 5 to 10 years. So I used to say, you know, I was too busy doing other things. Truth be told, the research wasn't there to pay attention to. And it was in 2016 when I was approached to write a book, And in chatting with my publisher, we were talking about menopause. We were talking about this concept of baby brain. Do women lose their minds when they become pregnant and mothers? No, they don't, is the short. That I sort of had an aha moment. I thought, I've spent all of these years working as a neuroscientist. I've been the owner and operator of a female body and brain my whole life, and I've never really considered how the two come together. And that was really where the idea of the book came, to take a womb-to-tomb tour through the female lifespan, looking at that through the lens of neuroscience. And it's been quite a journey. And it's— there wasn't a lot to begin with, let me say, even back in 2016. But there's just been this surge of research emerging within the last 5 years that's really exciting to see and to be cheering on from the sidelines.

I'm looking forward to uncovering some of that in our show. When we're thinking about, when you're thinking about female and male brains, we talk a lot about neuroplasticity on the show. And so do hormones play a role in brain plasticity?

Yeah, absolutely. So hormones, when you are a little fetus in utero, sort of set up that basic patterning of maleness and femaleness, both within bodies, but also within brains. But then as we go through childhood, little girls' and little boys' brains sort of develop very, very similarly. It's not until we reach puberty when we see sort of the surge of testosterone in males from their testes and the surge of estrogen in females from their ovaries and in females the establishment of the menstrual cycle that we sort of start to see this almost reemergence of plasticity in the brain. We know bodies go through puberty but brains also go through puberty. And these conversations that you may have had previously about the adolescent brain and how that sort of shapes and shifts and grows through the teenage years is triggered and guided largely by sex hormones. Estrogen's really interesting because obviously in females it cycles monthly. If you're not on the pill, you're not pregnant, all the way from puberty through to menopause. And one of the most interesting aspects of neuroplasticity we've seen, and I'm not sure whether your readers are familiar with the structure of a neuron and it has dendrites. Which are like input receivers. And on each dendrite will have lots of little spines. They're like little buds on a tree branch in spring, and they grow and sort of disappear and flourish and fall away. It's almost like the physical representation of plasticity. And in females, estrogen causes in some parts of the brain those little buds to kind of flourish and then fall away. So we literally see— neuroplasticity tracking alongside hormones or tracking alongside estrogen, at least in girls and women. And that phase of adolescent brain plasticity, both in males and females, is a very, very sensitive phase, a critical period of plasticity where what happens to the brain really, really matters. So as brains go through puberty, they become very, very plastic, very, very sensitive. To learning by experience. And in particular, that's learning cognitive skills, precisely the skills that you might learn as you're in high school, which is quite a nice coincidence that as we go through adolescence, we are learning calculus, we're learning physics, we're learning English, we're learning critical reasoning, thinking, all of those higher-order cognitive skills. And we're also going through a very sensitive plastic phase of social and emotional development. Again, that window is opened up by these sex hormones. And what matters more to a teenager than anything else? I have 2 teenage boys, so I know it's just belonging. It's having like a herd, it's having a tribe. Teenagers' focus moves away from their family to their friends and belonging and interacting with other people. They become very, very sensitive to that. And that's because the brain is in a very plastic state. of needing to learn by experience from other people. And it's really the hormones of puberty that have opened that window up. And then we see at other points in the lifespan, particularly pregnancy in women where we get this enormous surge of the hormone estrogen and various other hormones of pregnancy as well. And that puts the brain, the pregnant brain again in a real state of plasticity. And really in pregnancy, it's priming the brain, preparing the mind for motherhood and for learning to respond to a baby's cues. So yeah, broadly speaking, we see hormones playing an enormously important role in brain plasticity.

I definitely want to do a follow-up episode so everyone can look forward to the episode we do on— for mothers and, you know, parents, you know, and their brains because everybody has a lot of questions on that. As a recent parent, I certainly do. So stay tuned for that, everyone. And make sure you subscribe so you don't miss it because if you miss it, you'll miss a lot. So some of the questions our team had prepared were things like, how do female and male brains— how are they different?

I think when we ask the question, are male and female brains different, we're almost coming at it from a Mars— you know, men are from Mars, women are from Venus. So it's sort of versus, males versus females, almost as if we had 100 people in the room and we could open up their skulls and look inside and we would see, you know, half the brains would be pink for girls and half the brains would be blue for boys. we could almost sex a brain by looking at it in the same way we could sex a human by looking at what's inside their pants. And we can't do that when it comes to brains, just looking at one brain. I like to think of brains being like bodies because essentially the brain is part of the body. And particularly if we look pre-puberty, before the sex hormones start to come into play, we have little girls and little boys and they've got fingernails and fingers and toes and hair and cute smiling faces and eyeballs with retinas that connect to the visual cortex. There are so, so many similarities between bodies, whether they be male or whether they be female. But then again, there are some significant but small differences, mostly in terms of reproductive function. Once we start then going through puberty and adulthood and we start to gain different experiences in life, we do start to see that male brains and female brains show a few small structural differences. That may be driven by experiences of gender. There was a recent study that came out about a month ago from the journal Proceedings of the National Academy of Sciences that looked at how experiences of gender in different countries in the world could shape brain structure in different ways. But this isn't looking at individual brains, this is pooling together data from thousands and thousands and thousands of brain scans and using sophisticated AI and deep machine learning to analyze that data. And that was interesting because it showed that in countries with great gender inequality between males and females, female brains were more different than male brains. In countries where there is very little gender inequality, like here in Australia, male brains and female brains are much more similar. similar. But we're not talking about 2 brains here, we're just talking about broad averages. So, you know, we could look at these structural differences across the lifespan and we can kind of detect tiny differences later in the lifespan, but certainly early on, you know, brains are broadly similar.

Mm-hmm.

We've got these different experiences that emerge based on our biology, based on, you know, the experiences we have of the outside world. that are shaping and sculpting brains perhaps down slightly different paths.

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Yeah.

You talk a lot about limiting beliefs or anything that would help people to tap into more of their performance or potential?

Yeah, that's a great question because I think when I went into writing my first book in particular, I thought I'm going to be writing a book about the female brain across the lifespan. So it's all going to be about hormones, hormones, hormones. And sex hormones are important, but they're not the only thing. I like to think if you've got a brain in the middle of a in the middle of the world really, and you've got these biological bottom-up signals the brain is receiving. You've got the outside-in signals from the world, the rising and setting of the sun, the lived environment we're in. But very, very importantly, a large swathe of our brain, a large amount of cortical real estate is taken up with processing signals from other people. People's faces, the interactions we have with other people, their emotions. We spend an awful lot of time gauging other people and then we're making meaning of what's going on here. And what I found in my research, whether we were looking at newborn infants who need to attach to a loving caregiver, we were looking at young kids entering puberty and starting to feel self-conscious about how their bodies were changing in relationship to their friends, we're talking about parents sort of starting to struggle with feeling isolated at home with a new baby, we're talking about—

Teenagers.

you know, people in aged care who may have never had a visitor for 10 years. The greatest influence on health outcomes and on brain health is other people, are the social connections. That's where the greatest opportunities lie. It's also where the greatest risks lie when we're kind of lonely or when we're socially isolated. And that's very much the strongest predictor of mental health outcomes and the strongest predictor of of aspects of brain health when we look across the lifespan. And I think that that's really good news because it does give us a great deal of agency and understanding that we can— we have this real tendency, especially when we talk about women's health, to blame the hormones when things go wrong or to blame our biology or to blame our genes. We can't necessarily do a lot about that. But we know an infant needs a loving caregiver. We know teenagers need to feel like they belong to a tribe. We know new parents need social support networks around them more than anything. And that's a stronger determinant of the experiences we have, both from a neurobiological perspective but also just from our lived experience than anything. And it's very, very clear from the data. It doesn't matter which age we look at or whether we're zooming in and looking at the sort of Synaptic level of what's happening in the brain, network function, or health outcomes in a population.

So it's not just our neurological networks, it's also our social networks.

Yeah, absolutely. And our brains, when we see these significant plasticity shifts in adolescence and then in new parenthood, the shifts in those networks are really in social brain networks because we're social beings. And that's where I believe that the opportunities lie. We can spend a lot of time focusing in on personal optimization, kind of looking in, what can I do to enhance myself and to get better at this and that? When really our brains evolved to connect with others. And if we could sort of shift the focus away to the louder voice in the crowd is the other people, that gives opportunities also for us to start looking outward into supporting others, supporting children, supporting parents. I write books to support, get the message out of neuroscience out there into the world. Focusing in on internal self-optimization can sometimes cause us to look inwards too often. And that can lead to a real sense of sort of self-isolation. And as soon as you start to become a bit, you know, you spend too much time navel-gazing, turning inward means you're not turning outward and connecting. I mean, we all went through COVID everywhere in the world. We all knew what it felt like to be socially isolated from others and the mental health outcomes.

Yeah.

and ramifications of that. And our brains are wired to connect. So we should— that should be where our focus lies.

Yeah. And I want to address both those meaningful connections that we have within our external world and then, you know, people feeling good about themselves, you know, in terms of their own identity and potential. So when we're talking about connections with others, do you have some insights On, you know, scientifically backed ways to bridge communication, whether it's between genders, fostering healthier, more meaningful connections and relationships?

I'm not sure whether— I think neuroscience tells us what's important. It doesn't necessarily always give us a guidebook on how to do that. What I have learned from all of my studies in neuroscience is It also reminds us that we're mammals. I'll give the example of, 'cause I've got teenage boys at the moment and I tell you what, male puberty is wild. Sometimes feel like I'm just watching a science documentary. And for me, what the neuroscience and understanding the social brain has given me an understanding is what's sort of typically and healthy and normal. So my oldest son, he's sort of 15 coming on 16, going out into the world, he's 6 foot 5. He's 4, full of bravado. We live on the beaches in Sydney, so he's got a ton of freedom. But, you know, of course, like any, you know, good mom, I've said, anytime you call me, I will come and pick you up. On the phone, anytime, no matter what. And so, what does he do? Calls me from the school bus, which drops him about 800 meters up the road. Mom, I'm really tired. Can you come and pick me up? And I'm like, well, I work from home. I've promised that I will come and pick you up if you ever call. So, I'll drive 800 meters up the road, pick you up in the car, bring you home. He goes upstairs. takes off his school uniform, comes back downstairs, goes out to the garage, gets a surfboard under his arm, gets on his e-bike and he says, I'm off. And I'm like, oh, didn't think you had a ton of energy. Do you want me to drive you somewhere? He says, no, no, no, I'm gonna go and meet my mates down at the beach and we'll go for a surf and I'll see you later. And what understanding the social brain has taught me is that the way he is behaving is completely developmentally normal and I should feel very grateful for that. Because what gives us energy, what motivates us, what drives us, particularly if you're a teenager, is the need to belong. So he had no energy, he had no drive, he had no motivation to get off the school bus and come home. But as soon as there were social connections, he suddenly had energy, he had motivation, he had drive. And it's given me the grace as a parent to not think, gosh, you're selfish. You'll call me when you need me. It's to understand that the way he is behaving is completely developmentally normal for an adolescent brain that is driven to connect, that is driven to be part of a tribe. So it hasn't given me a blueprint for teaching him how to connect, but it's enabled me to stand back and, like I say, watch this kind of nature documentary emerging in front of me. And it gives me compassion, it gives me understanding to let him behave in a completely developmentally normal way. I will say that on occasion I have said to both of my— I have a 13 and a 15-year-old son, they'll do something or say something and I go, darling, you're completely developmentally normal. And the response I get back is, you're completely developmentally normal, which is completely developmentally normal response to their mother trying to talk to them about neuroscience. They're not really interested. So for me, understanding the absolute need we have and letting that happen is As, as what neuroscience research has given me.

You mentioned, uh, self-optimization. Um, I, I know some of the people are listening, they, they do have an interest in, um, being the best version of themselves performing. And do you, have you come across any insights, uh, you know, maybe evidence-based tips or lifestyle changes, whether it's for women or men that people can incorporate into their daily routines to just, uh, to have better brain health?

Yeah, for sure.

Or to enhance their overall just Mood and wellbeing even.

Yes, sleep. One thing, sleep. That's the— I'm sure you've talked about that 1,000 times, but if you haven't got—

It bears repeating.

Yeah. If we don't have our sleep sorted, everything else falls apart. It is the foundation on which all good brain health is built. And I am obsessed with sleep. Not a lot gets between me and my pillow. You can ask my husband that. I love my sleep and I'm very protective of it. I can be quite precious about it, in fact. And I have And I'm continually trying to integrate new ways to optimize my sleep because I know how I feel if I miss one night's sleep. It's very hard for new parents, of course. Mother Nature seems to slip up there. We don't really have any kind of neurobiological mechanism in place for ensuring that little babies sleep and we can get the sleep we need to, apart from the fact that we should be sharing care. Between adults. But I, you know, I do all of the things. I, you know, I don't allow screens in the room. As we were talking about this before, the best time to do a podcast for me is early in the morning. I try not to do anything after 5 or 6 PM at night. I would rather cook a lovely dinner, wind down, hang out with my family. If it's summer, take the dog for a walk. I go to bed early. And then, I mean, we're very fortunate where we live here in Sydney. Our house faces east and we've got a beautiful outlook over the ocean. And me and my husband to sleep with our curtains open so that we naturally wake up as soon as the sun kind of peeks up over the horizon. You know, personally, I suppose I've said you can spend too much time personally optimizing. If that's all you do, you'll become lonely. But for me, sleep is the foundation for all good health.

And good relationships. You know, I know when we don't get good night's sleep, you know, we're not the most fun to be around.

No.

And wanting to connect and be super social and understanding and empathetic. Yeah, it's really hard to be kind and empathetic empathic when you are really, really tired.

And I'm sure as a new parent, you're experiencing that. And that's, you know, we can talk about that in the pregnancy motherhood podcast, but tag teaming is great, giving each other time. You know, you've got to kind of come up with a relay system, I think.

Well, I appreciate it, Sarah. Everyone go get the copy of the Women's Brain book, Neuroscience of Health, Hormones, and Happiness. Where can people connect with you?

Yeah, so my website is probably the best place to start, drsarahmackay.com. And, you know, you can follow the pages through there to buy my book. If you're in the US, it's available on Amazon. And there's also Audible versions of my second book only, sadly. But you can, you know, find all that, links to my online training programs, blog posts, various podcasts and media, TV, that I have done here in Australia. So people will be very welcome.

Your social media as well?

Yeah, social media. There'll be links through to Instagram where I spend most of my social media time. Again, that's Dr. Sarah Mackay on Instagram.

Perfect. And we will put all— as always we do, we put the amazing show notes for all our listeners and viewers at jimkwik.com/notes. And so highly recommend it. If you enjoyed this episode, make sure you share it. I would recommend you take a screenshot in whatever platform you're consuming it, whether it's on YouTube or Spotify, Pandora, iTunes, you name it, and tag us both so we get to see it. Sarah, thank you so much for being on our show. We can't wait to do the follow-up to talk about baby brain. And everyone who's listening, make sure you subscribe. Thanks, Jim. Probably the best place to subscribe is on YouTube. We have over a million subscribers there. We also put the extended version of these conversations. In all audio forms, we keep it to 20 minutes or less, but on YouTube, we tend to go a little bit longer. And also, I upload some of our talks and other special gems there as well. And if you got extreme value out of this conversation, the best thing you can do is leave a review because your joy stories, people that can relate to, It allows us to help us on our mission to build better, brighter brains. And so, Sarah, thank you again.

Thank you, Jim.

And everyone who's listening, be limitless. We'll see you soon.