THE FEMALE BRAIN: Is It Hardwired Differently

Are male and female brains wired differently ?

American psychiatrist, Dr Louann Brizendine, says physiological, hormonal and genetic differences mean men and women think differently.


The more we learn about the brain, the more biological difference scientists find. But what these differences mean is hotly debated.

In her best selling book, ‘The Female Brain’, Louann Brizendine, controversially argues there’s an evolutionary basis to the difference.

Dr Brizendine runs a women’s hormone clinic at the University of California, San Francisco. She claims sex hormones have a powerful influence on our brains.

The result? The male brain thinks about sex more frequently than the female brain. Women are wired to seek social harmony; men to be more aggressive. And women are more interested in and attuned to the nuances of emotion.

This week on Insight, Jenny Brockie explores the question of gender and the brain in a spirited debate with a group of very diverse guests.

Neuroscientist, Professor Lesley Rogers, agrees there are biological differences in brain structure, but argues the link with how we think and act has not been scientifically established.

Do men and women really think differently? And if so, how much is this about nature and how much about nurture ?

Is the female brain hardwired differently? Are men and women pre-programmed to think and act differently? A new best-selling book by American neuropsychiatrist Louann Brizendine argues just that. So how much of our biology is our destiny?


REPORTER: Shaun Hoyt

REPORTER: Do you think that boys and girls think differently?

GIRL 1: I think they do because boys are a bit more like into violence maybe sometimes and, um, they're a bit less talkative than girls, I think.

GIRL 2: Boys like Transformers and those stuff but girls like ponies and those different stuff like dolls and stuff.

BOY 1: Some boys like army stuff and some girls like Barbie stuff and stuff like that so it makes them think differently.

GIRL 3: They think quite differently but they don't think as differently as they did in, say, the 1950s.

BOY 2: Girls sometimes are more mature than boys. I don't know why, it just seems that way.

GIRL 4: Girls seem to concentrate a bit more.

BOY 3: Well, yes, they have the same brain but they think different thoughts.

GIRL 5: The male brain usually weighs more than the female brain except that doesn't mean that the men are more intelligent.

REPORTER: Who are you friends – mostly boys or mostly girls?

BOY 2: Boys.

GIRL 2: Girls.

BOY 4: Boys.


BOY 1: Well, they just interest me more than girls.

GIRL 6: Girls.

GIRL 5: I'd probably say that I'm in between. Well, I don't play with Barbie dolls except I do watch, like, 'Pirates of Caribbean' and 'Lord of the Rings'.

GIRL 7: I reckon a tomboy is a person who likes boy stuff but is not…is… that is a girl but likes boy stuff but they can still play girl stuff as well. They don't have to just be a boy stuff.

REPORTER: And that's how you are?

GIRL 7: Yes.

GIRL 8: Mostly girls but I do have friends that are boys as well, you know. But you don't really play with them in the playground much.

BOY 5: Mostly boys.

GIRL 1: I usually play with my friends who are girls and we talk a lot about like what's been happening.

REPORTER: Don't you like boys?

GIRL 6: No.

JENNY BROCKIE: Well, welcome everybody. This is going to be very interesting, I think. And, Louann Brizendine, I'd like to welcome you from San Francisco. You've written this controversial book called 'The Female Brain'. Tell us how radically different you think the brains of men and women are.

DR LOUANN BRIZENDINE, AUTHOR ‘THE FEMALE BRAIN”: Well, thanks for having me, Jenny, and thanks to all of your audience for being here. I think that what's important to know is that we all start off at conception with a female-type brain and then at eight weeks of foetal life, the tiny testicles in the male foetus start to pump out large amounts of testosterone that go and marinate the brain, changing the brain circuits from female-type brain circuits into the male brain circuits. So by the time we're all born we have a female-type brain or a male-type brain and that means that the testosterone fertilises the area for sexual pursuit in the male brain, and in human males that area's 2 to 2.5 times as large in the male brain. And then the areas..

JENNY BROCKIE: As the female brain…? You mean it's 2.5 times bigger than in a female brain, that area for sexual drive?

DR LOUANN BRIZENDINE: Yes, that's correct.

JENNY BROCKIE: OK, keep going. Sorry to interrupt you.

DR LOUANN BRIZENDINE: In the male – that's alright – the testosterone changes those by fertilisation. Other areas in the brain, the testosterone probably does something we call decreasing it in areas that have to do with emotional detailed memory. We know, for example, in female brains it's a bit larger and women have been known by criminologists and other forensic scientists to know that we actually remember what's called emotional detail for many more years than a male. An example of that is a male and female may have a fight and she remembers 10 years later all of the things that happened in that fight and he may forget that the argument ever happened at all.

JENNY BROCKIE: OK, if you had to If you had to isolate what you think the key things are that are different and how they affect behaviour, different behaviours in men and women, what would they be, just quickly? What do you think are the key differences in the brain that lead to key differences in behaviour?

DR LOUANN BRIZENDINE: Well, we know that the brain circuits that are female type run then on high-test oestrogen during the female's lifetime and the male starts to run from age 9 to 15, his testosterone level increases 25-fold. His brain circuits then start to run on that particular hormone. So both the brain circuits and the hormonal fuel that runs those circuits are different in the male and female brain, which really settles in by puberty age – say, 13, 14, 15, boys versus girls.

JENNY BROCKIE: We're going to get on to some of the specifics a little bit later and some of the specific aspects of behaviour, but I wonder how people feel just listening to some of this. Katrina and Mark, for example, you're a couple. Do you think your brains work differently?

MARK RIESEL: Sorry, I wasn't paying attention.

WOMAN: Need we say any more?

MARK RIESEL: I was just thinking about work and sex.

JENNY BROCKIE: You were thinking about sex, yeah. So are you going to answer the question?

MARK RIESEL: Well, you asked Katrina as well. No, look, I don't think that you can necessarily say that it's divided into male and female in black and white terms. For instance, if I observe my daughter, she reminds me in many ways of my sister. She was… my sister was highly articulate at a young age and so is my daughter. And my son, who's only just about a year and a half younger than her, um, speaks very well. But he's got friends who are amazingly articulate, male friends. So I think, OK, well maybe it's not a male/female divide.

JENNY BROCKIE: And, Katrina, what do you think?

KARTRINA RIESEL: I used to think socialisation made the difference with children and then I had my own, and I can honestly say we've got both boys and girls and I think we've brought them up pretty similarly. Um, we offer them all the same interests, we speak to them the same way and, trust me, girls are very different to boys.

JENNY BROCKIE: How? How do you think they're different?

KATRINA RIESEL: Well, how can I explain it very quickly? I told my daughter tonight's topic – she's nine years old – and I only told her the topic and she said, “Does that mean you're going to say I'm bitchy and the boys rumble?” And I thought, “There you have it.” Just like those kids, straight out of the mouths of babes.

JENNY BROCKIE: Jayashri, you're a professor of psychiatry. I just wonder what you think about this theory and this idea from the clinical observations you've made. We're not talking just about behaviour. We're talking about the way people's brains actually work. Do you think there's something in this?

PROFESSOR JAYASHRI KULKARNI, PSYCHIATRY, MONASH UNIVERSITY: Yes, I do think there's something in this because we do need to consider what the hormonal environments are and the impacts that different hormonal environments' dominance have on developing brains. I do agree with the couple over there in the sense that there are obvious socialisation aspects, and that nature/nurture argument, there's no straightforward answer to it. It's always going to have bits of both but we do need to take the hormonal aspects into account very strongly.

JENNY BROCKIE: And how strongly do you think that drives what we do? We all know behaviour and nurture does play a role but how strongly do you think we are driven by our biology?

PROFESSOR JAYASHRI KULKARNI: Well, I'm working, obviously, in the disease end of the mental state spectrum and certainly in the disease end of spectrum I think the hormonal aspects have a major part to play, particularly in some of the disorders like depression and other major, major psychiatric disorders. Not the only factor but an important factor.

JENNY BROCKIE: And what about other behaviours? What about the kinds of things that Louann was talking about?

PROFESSOR JAYASHRI KULKARNI: Absolutely. There are all sorts of different programming issues but that's not again to say it's as black and white, as I think Louann is clearly stating.

JENNY BROCKIE: So you think there are more shades of gray?

PROFESSOR JAYASHRI KULKARNI: Yes, I'm going to be wussy and sit in the middle.

JENNY BROCKIE: OK, Amanda, are you going to be wussy and sit in the middle on this? Now, you deal with blokes in politics all the time. Do you think women's brains work differently to men's brains, from what you've seen in politics?

SENATOR AMANDA VANSTONE, FEDERAL LIBERAL:I've not the slightest doubt, not the slightest doubt. I can't say whether it's as a consequence of biology or cultural upbringing but we end up fundamentally different.


SENATOR AMANDA VANSTONE: Well, I think men have a predisposition to focus more perhaps on These are generalities. I mean, there's always generalities and differences. Generally I think men are very much focused on their career, they're more type-A aggressive, get on with it. Women I think are more likely to have an outcome in mind, a policy outcome in my case, but an outcome in another field. Um, men I think are very sensitive to criticism where as women, I think, are just used to being criticised all the time. If you say to a bloke, for example, “That's a stupid idea,” he will not wilt – quite the opposite – he will arm up mentally and come back at a very aggressive way, and he's not even interested in the conversation. But if you say to him, “That's a really interesting idea and I know other people who think that. Just before you make up your mind, um, there's a few things you need to consider,” he'll think about it. So they are wired up to be aggressive and, if you're aggressive with them, the barriers go up.

JENNY BROCKIE: But you're not exactly a shrinking violet either, Amanda.

SENATOR AMANDA VANSTONE: No, but I think that's a function of where I work and I always say to my colleagues if you're not bitchy to me, I'm not going to be bitchy back. I've a general view – you be nice to people until they have a go at you and then you have a go back.

JENNY BROCKIE: All bets are off.


JENNY BROCKIE: Jack, what do you think? You run an ad agency. Do you agree with what Amanda's saying?

JACK SINGLETON, ADVERTISING EXECUTIVE: Yeah you would never… The most important part of the brief when you get the brief for a product or a service you've got to advertise, is who's the target audience. And if it's a woman or a group of women, then the kind of ad where you would run the ad, what you say in the ad, the kind of ad you'd make is entirely different to an ad you'd make for a man.

JENNY BROCKIE: But I guess the point of tonight's discussion is how much is that about what Louann's saying driven by biology and how much of it is just learned?

JACK SINGLETON: I think it's I mean, 400 million years of evolution, men have been evolved to be very good at what they do and I think it is the testosterone that you get inside a man, I guess, as it was eloquently put, the brain marinates in this testosterone.

JENNY BROCKIE: So it's just a wonderful image.

JACK SINGLETON: I think it's wonderful to know. Now I've got an excuse for the way I behave. I say it's the marination process. Don't blame me.

JENNY BROCKIE: And what is the way you behave?

JACK SINGLETON: Like a man. Yeah, I do think about work and sex and very little else.

JENNY BROCKIE: Lesley Rogers, you're a neuroscientist and I know you take issue very strongly with this idea. Tell us why.

PROFESSOR LESLEY ROGERS, NEUROSCIENTIST AND AUTHOR: Well, I like to see the science in it. People have opinions, they are part of the cultural division between men and women, but let's look at what's actually measured and what really is different between men and women and certainly you can find differences. They're not as large as we often make, there's a large overlap.

JENNY BROCKIE: Now, this is the brain we're talking about, not just…?

PROFESSOR LESLEY ROGERS: Well, in behaviour there are differences. There's many psychophysical tests that have been done. Women hear sounds at softer levels than men do, and so on. But this is not an absolute difference. This is a mean difference, an average difference, and there's a large overlap. Now, but the important question is, given these differences, albeit not as large as a lot of people would like to think, what actually causes them? And that's where I really part company, because this sort of simplistic explanation for very complex human behaviour is, in my opinion, just…well, it's not really science at all. It's pseudoscience. We don't know the answers to these. Quite clearly it's a complex interaction.

JENNY BROCKIE: Do you accept anything of what Louann's saying? What do you accept in terms of differences in the brains?

PROFESSOR LESLEY ROGERS: No, I don't accept these metaphors of brains marinating and so on. They make good stories that people pick up. But as a scientist, who studies development, I know full well that in any kind of behaviour there are genetic components, there are biological components but there are also environmental and learned components, all of which interact at different stages of development and in extremely complex ways.

JENNY BROCKIE: Louann, what evidence do you have for the kind of assertions you're making?

DR LOUANN BRIZENDINE: Actually scientists do use the word 'marinate' because they have known for 40 years that the testosterone that marinates the foetal brain changes the circuits and increases the size of those areas of the brain that are larger in the male brain. For example, the area that's best known for 40 years is the area called the area for sexual pursuit, it's twice as large or more in the human male than the female. But I think I want to have everybody know that we have to honour the variety. Each individual is not an average. Each individual has its.. For example, I was one of those girls that was more a tomboy. I mean, I liked to run around the backyard and climb the trees with the boys, although I also liked to make some clothes for my dolls. So, you know, there's all kinds of different behaviours and you don't want to put a stereotype on anyone and say, “You are this way and you have to behave this way.” That's horrible.

JENNY BROCKIE: I'd just like to pursue this matter of science. Marcello, you're also a neuroscientist. Are you convinced there's science to back this up?

PROFESSOR MARCELLO COSTA, NEUROSCIENTIST, FLINDERS UNIVERSITY: The brain is definitely different, the hormones are definitely different, some of the genes may be different. What I don't accept entirely, and I agree with Lesley to this point, and as more criticism to Louann, is that to link this together, the structure and function, and to reach the conclusion that you are reaching in such a firm way is very misleading to say the least, because you're pointing in the right direction but it's also very final. You sound like there's no more need for any research. Well, I think it's just the beginning.

JENNY BROCKIE: Milton Diamond in Hawaii, I'd like to just bring you in at this point. You've looked at gender – this issue of gender – for decades. How much are we hostage to what is going on inside that brain, regardless of nurture?

DR MILTON DIAMOND, PROFESSOR ANATOMY, UNIVERSITY OF HAWAII: Well, 50%. If you want a round number, 50% is going to be due to the nature and 50% due to the nurture. But what happens is that in the book or in things, in understanding the behaviour differences in men and women, we look at the behaviour and attribute that to the brain. We don't think it's in the kidney, we don't think it's in the liver, it's got to be in the brain. The problem is we don't see pink and blue in the brain. We're not going to see many large distinctions. We're looking for them and obviously some are mentioned in the book but take the biggest thing, for example, menstruation. Women menstruate, men don't, but you're not going to find a piece in the brain that says this is pink and this is the woman menstrual place. Yes, we know the pituitary and the hypothalamus work to do this but we can't find the cells that do it. So to look for the cells that talk about arguments, that talk about a memory of love or something like that, I think we're premature. I think it's there but I don't think we know how to look for it exactly now.

JENNY BROCKIE: Well, we're going to have a look in a moment at how our brains might affect our attitudes to sex, the different sexes' attitudes to sex. But first, Shaun Hoyt with someone who believes she's living proof being female is all in the mind.


REPORTER: Shaun Hoyt


Rachael Wallbank is a family law solicitor at Port Stephens, a peaceful spot on the NSW coast. Life hasn't always been so calm. That's because Rachael grew up as a boy called Richard.

RACHAEL WALLBANK: God made me with a female brain in a male body.

Richard was just a child when he realised he was different.

REPORTER: What made you so sure about the fact that you were really a girl?

RACHAEL WALLBANK: It's hard to know, it's hard to know. I think it's… It comes from experience. I'd experienced what the girls I grew up with were allowed to do, and that's what I wanted to do, and I wanted to play with them, and I didn't dislike boys but I also wanted to do things girls did. And certainly by the time I was six or seven, when I was found dressing up in my sister's clothes, that's when I knew That's when I was told it was wrong by Dad and that's when I told Dad that I was really a little girl.

His worried parents sought help.

RACHAEL WALLBANK: Once this all… visit to the child psychiatrist occurred, I really tried to fit in. So I was the.. If there was rough and tumble going on at school, I tried to be the roughest and, you know, tumblest.

Richard Wallbank became a lawyer, married and had three children but by his late 30s his marriage was failing and he felt as though he couldn't go on.

RACHAEL WALLBANK: If I could have stayed a father to my children, I would have. I've shed rivers of tears about that. I really wanted to be a dad for my children.

At 38, with the help of surgery, Richard became Rachael. These days Rachael still practises law and remains close to the children but the rest has changed.

RACHAEL WALLBANK: One way to describe what it was like trying to be Richard was like breathing underwater where as now I was able to come up for air as Rachael and, um, you know, people said, “What's the most important thing? What was the biggest difference? Was it being able to use make-up or the clothes?” And it wasn't. It was being able to have female friends and being able to have female conversation.

So does Rachael believe men and women think differently?

RACHAEL WALLBANK: I'm convinced that men and women think differently because of my own experience. I think females are far more prepared to at least explore feelings and far more concerned with how they're experiencing the world and they're prepared to really get honest with each other. Men would much more talk about what they're doing in the world and what things they've been able to create or achieve or play with than, um, than about actually how it is for them.

Rachael believes science has finally caught up with what she knew all along.

RACHAEL WALLBANK: If I could have, I would have changed my mind and I spent a lot of money trying to do that, but the.. It's accepted now that, you know, that's a waste of time, that we're stuck with our minds and when it comes to sexual identity, it's what's between the ears that counts, not what's between the legs.

JENNY BROCKIE: Well, welcome, Rachael. Thanks a lot for joining us and you do clearly believe you have always had a female brain of the kind Louann's talking about?

RACHAEL WALLBANK: That's right, no doubt. And it's no doubt because in fact it's the only thing that explains my life and my predicament. And as I said, I mean, if I could, I would have walked over hot coals in order to, you know..Who would risk the affection and friendship of family, friends and career, um, for just to throw on a frock? If it was all just about gender experience or expression, I could have got away with that. There are plenty of people that do. But I needed to bring my body into harmony with my mind in terms of my sexual identity in order to have any peace in the world.

JENNY BROCKIE: Lesley, I'd just like to ask Lesley about this because, Lesley, I wonder what you make of this. I mean, isn't this a really good example to back up Louann's theory that there is such a thing as a female brain?

PROFESSOR LESLEY ROGERS: I don't think it backs up the theory. I accept the way Rachael feels and I know there are many people who feel like that. We don't really have the explanation for it. I think there's I agree with what you're saying. There's a genuine contradiction in what she's saying. On the one hand she's giving the brain flexibility. On the other hand she rigidifies it by saying in the evolutionary psychology terms as being the selection for difference between men and women and somehow assumes that we know what kind of selective pressures were going on a million years or so ago. These are all assumptions. They're not…

JENNY BROCKIE: So you're talking about Louann's assumptions but what do you say to Rachael when Rachael says to you, “I know I have a female brain and I have always had a female brain, even when I had a male body.” What do you say back?

PROFESSOR LESLEY ROGERS: I accept that. It would be nice to actually have some more research that actually measures and looks at those things.

RACHAEL WALLBANK: There's plenty going on. There's some being done, I know. The problem with your position is that you don't have an explanation for me. That does.

PROFESSOR LESLEY ROGERS: No, no, no. You think it's the hormones.

RACHAEL WALLBANK: No, I think whatever variability the brain has, you know, in terms of knowing and experiencing yourself as either a male or a female, that's locked in, and that's locked in by the time you're three or four years of age, on the science that I'm aware of.

PROFESSOR LESLEY ROGERS: In our culture that sort of Where we've got a culture that's strongly divided along male-female lines, people will choose perhaps very early in life where they belong and they maybe..

RACHAEL WALLBANK: I was captain of the forwards in the second XV at St Pat's, Strathfield.

JENNY BROCKIE: Can you say that again?

RACHAEL WALLBANK: I was captain of the forwards in the second XV at St Patrick's, Strathfield. You know, so I could play the game for a while. But it was just like a huge weight and I was never sure of where I was amongst a group of guys, just adlibbing all the time. It was wearying, Lesley, and the implication of what you say is it's a psychological feeling where as I know better than that. I know it was determinative of my life, because I've suffered for it. People don't be different like this for the fun of it. It's just – it's an experience.

PROFESSOR LESLEY ROGERS: But the same thing can be said, say, of the so-called gay gene that's hypothesised. Now, you know, a lot of gay people said, “That's great, if there is a gay gene, then we have no reason, no cultural reason to be ostracised. We've now got a biological reason.”

JENNY BROCKIE: Is that what you're worried about? Are you worried about how this might be used, this idea of the female brain? Is that your concern?

PROFESSOR LESLEY ROGERS: I'm very concerned about this way of thinking. It's very dangerous because it puts people in boxes, it removes fluidity from society, and I'm not saying..

JENNY BROCKIE: Aren't you putting Rachael in a box in a sense? She's telling you who she is.

PROFESSOR LESLEY ROGERS: Rachael put herself in the female box and that's fine, I'm very happy with that.

RACHAEL WALLBANK: That's the point I'm taking up, Lesley. I didn't put myself in the female box.

PROFESSOR LESLEY ROGERS: Somebody… Biology put you there.

JENNY BROCKIE: Milton Diamond, can I ask you, you do research in this area, does the science back up Rachael's experience, in your view? Is there science to suggest that's the case?

DR MILTON DIAMOND: Well, I certainly believe so. Well, I happen to I happened to actually be involved in some research right now. We're doing what we call the dichotic listening. Males and… just the way people are right-handed or left-handed, they're also right-eyed or left-eyed and they're also right-eared or left-eared. In other words, you hear better in one ear than the other. And there are male and female differences for populations. Not everybody is different but there are population differences. Well, what we did, and are doing now with a colleague, Ernie Grovier from University of East London, we're doing what we call dichotic listening. In other words, we put earphones on the individual and in one ear we have a sound that might be 'bip' and in the other ear we hear 'bop'. And so we ask the subject, “What did you hear?” And generally women will hear better in their right ear than their left ear and men will hear better in their left ear than their right ear. Most of the transsexuals, the male-to-female transsexuals, hear like women. Now the only place that's going to end up different is in their brains. That means the circuits are different. So that's the type of evidence we're developing now.

JENNY BROCKIE: Louann, let's get down to some basics here. Now, you say one of the key differences between male and female brains is that men think about sex much more than women do. What's your evidence that that is because of what's going on in the brain, rather than something that's just…?

DR LOUANN BRIZENDINE: We know that the fluctuations in the hormones through the menstrual cycle, for example, the hottest period of a woman's month, say, when she may be more interested in sex is the two or three days before ovulation, when her oestrogen and her testosterone level are at their peak. So that matches up with the behaviour that's been shown in study after study after study. The part about women's roles changing and women's biology and brains and sex drive and interests, and we all know from experience men and women can do the same things, like be doctors, lawyers, astronauts, engineers, leaders, we have to know that there's an evolution going on culturally and socially as well. It is not putting people in boxes.

JENNY BROCKIE: But you are… but you are making the point that the section of the brain to do with sex drive is physiologically different for a man than it is for a woman and that that accounts for why men are more inclined to think about sex all of the time or a lot of time. Is that the point you're making?

DR LOUANN BRIZENDINE: Yes. So we have to honour some of those biological differences that have been repeated in study after study after study on the typical average and know that individuals can vary.


PROFESSOR LESLEY ROGERS: It's not a matter of honouring any sort of biology. In fact biology is a lot more flexible and overlapping between the sexes than people acknowledge. The hormone testosterone, which we call the male sex hormone, is also released in women and in fact in many women the level of testosterone is higher than it is in men. So culture and society makes a much greater division between the sexes than does biology itself. It's much more flexible.

JENNY BROCKIE: Do the men in this room think they think about sex much more often than women do?

MAN: How do we know?

JENNY BROCKIE: Well, I'm asking you.

MAN: I haven't got a woman's brain.

JENNY BROCKIE: I'm asking you how often do you think about.. It's an interesting point. Do you think in general that men think about sex more often than women do?

WOMAN: They admit it to it more often.

JENNY BROCKIE: They admit to it more often. That's an interesting point. Do you think that's true? This lady here thinks so too. Well, I'm very interested in whether that's the case. I mean, do you think it is about fundamental differences between men and women, or do you think it's not?

WOMAN: Well, you see, my opinion is that it's layers, the whole thing is layered so that everybody's different. It's all interwoven and you can't I don't believe you can say men are like this and women are like that.

DR SUSAN MAUSHART, COLUMNIST AND AUTHOR: Can I just say, it takes a level of leisure to devote that much time to thinking about sex too, you know, and this is another aspect of women's changing roles and that's why I think the younger generations are sort of.. They're evening up the score a bit. They're not so, you know, they're not so weighed down.

JENNY BROCKIE: How often do you think about sex, Susan?

DR SUSAN MAUSHART: More often than I'd like to admit on a family program.


JACK SINGLETON: A fair bit. A reasonable amount, but if women do think about sex as much as men do, or more so, I'd find that disturbing. It wouldn't leave them a lot of brain space for thinking about anything else, really.

JENNY BROCKIE: So how do you run the ad agency?

JACK SINGLETON: Very poorly.

JENNY BROCKIE: Mark. Sorry, Mark. Sorry, Mark. I just wanted to ask you.

MARK RIESEL: I think that what was said, that it requires a certain amount of leisure because if you're doing one thing you can't be doing another – we can multi-task, we can be at work and we can think about sex.

JENNY BROCKIE: And, Katrina, how often do you think about sex?

KATRINA RIESEL: I actually think about it quite a lot but when that sun goes down and my head hits the pillow, do not come near me, I just want to go to sleep.

JENNY BROCKIE: That's because you've got four children.


JENNY BROCKIE: Rachael, I'm interested in what you think about this because you're an interesting example. I wonder, were you thinking about sex more when you had a male body than later, when you changed?

RACHAEL WALLBANK: No, no, not at all. In fact there was a lot more – I couldn't get the magazine – the visual stuff, you know, that was the constant, you know, that there's a trite way of talking about sex which is, from my point of view, a male way of talking about sex. It's trite, it's only surface-deep where as my female friends don't talk about sex like that at all. They talk about sex but it's a completely different way of approaching the whole topic.

JENNY BROCKIE: Marcello, what do you think about this?

PROFESSOR MARCELLO COSTA: I also feel, probably one of the few male neuroscientists here, that we are probably different and we think differently but it is also fair to say it's unlikely we're going to find in the very gross anatomy of the brain the reasons. For as important as they are in evolution – and I think nothing is important in biology except evolution – but also I think, and I agree with Mike, that there's subtle differences, for instance, in Rachael's brain from the very beginning too small to be detected either by hormones, even by genes, and certainly by brain imaging. They are definitely there because we have to rely on the personal experience, but the difference may be very small and it's only very recently that we are beginning to visualise what goes on in the brain. It was a black box. We now begin to see where and when things happen but it's just at the beginning. So I certainly encourage a person like Rachael and all the people like her that would be a perfect example of investigations to see whether there really are different subtle differences in the neuro-circuits. They are just as biological underlying behaviour as the hormones.

JENNY BROCKIE: Amanda, what do you think? Just getting back to the question of emotions, because a lot of women talk about this. Do you think there's a big difference in this area of emotional life between men and women and do you think it could be explained by biology?

SENATOR AMANDA VANSTONE: I can't answer whether it can be explained by biology. I think I did biology till Year 9 and moved on to other things so I'm not going to try and go there. But clearly, clearly they're different. I think men.. I'm not sure they really do want to talk more about their emotions, as some of the guys have said. I'm not sure that they do, or perhaps the generation I deal with, they'd really rather leave all that. That's girls' business. They're men, you know, they get on with things. They do things, and they don't sit around and talk about how they feel where as I think women do get great satisfaction and pleasure about sharing their views on how they feel about something.

JENNY BROCKIE: Does that play itself out in politics, that difference, do you think? Or in politics is it a different game altogether?

SENATOR AMANDA VANSTONE: Well it has an impact, an impact, but no more than that.

JENNY BROCKIE: What sort of impact does it have?

SENATOR AMANDA VANSTONE: Well, if you're discussing something that has an emotive aspect to it, the women will pick up that thread of conversation far more than the men will. I don't think women, for example, discard the monetary side of a political discussion. Can we afford it? How long will it take to pay back? Whatever. Women still do all that perfectly well but I think they are better at articulating their own emotional response and what the emotional response of the people in the community might be.

JENNY BROCKIE: We'll get back to this in just a minute and we are going to look at the controversial theory of the “mummy brain” – what hormones might do to a woman's mind. Louann, one of the more controversial things you have written about in this book is the mummy brain. Describe the mummy brain for us.

DR LOUANN BRIZENDINE: I think one of the things that evolution has done is selected women versus men in areas of their reproduction, like the mummy brain, to be obviously different. The mummy brain is the core of the issue in that during pregnancy our hormones, oestrogen and progesterone go up 30, 40, 50 times, they stay up high. At birth, then, big squirts of oxytocins are coming out into the female brain, it causes the uterus to squeeze and go into contractions and squeeze the baby out, the breasts to squeeze milk out and then also oxytocin is the hormone we talk about as the bonding hormone, creating almost aggressive maternal vigilance for protecting the baby.

JENNY BROCKIE: But what's actually going on? The circuitry in the brain.. That's what I was going to ask you. Go on.

DR LOUANN BRIZENDINE: And the maternal brain circuits that actually are, we assume, are laid down already, really get turned on, the switch gets thrown by the oxytocin and hormones of pregnancy and labour and delivery and then breastfeeding to be maternally vigilant with the child, and we know for several of years now, we have several studies that show there's actual changes in the female brain during pregnancy and after birth, and of course we know there's lots of hormonal and emotional changes often after birth.

JENNY BROCKIE: And are you arguing that women's brain power is affected by that, their capacity to do other things?

DR LOUANN BRIZENDINE: Women's brain power is highly focused. It becomes very vigilant and intensely attentive, both motivated and focused on tracking that little infant everywhere and, you know, that never stops. So we know that the circuitry actually gets what some women call smarter and more focused on the baby and maybe having more difficult time focusing on other things that don't have to do with the baby.

JENNY BROCKIE: So you're saying it could be at the expense of other parts of their life like work, for example?

DR LOUANN BRIZENDINE: Or, for example, like husbands. The poor husbands often get left out a lot, yes.

JENNY BROCKIE: Jayashri, what do you think about this theory?

PROFESSOR JAYASHRI KULKARNI: This is a very controversial area and it's important that we have a bit of discussion.

JENNY BROCKIE: Why is it a controversial area?

PROFESSOR JAYASHRI KULKARNI: Because if you follow this argument through to its conclusion it means that basically women have the risk of when they're pregnant or post-partum that they're basically demented pieces of no use to anyone, and that is a problem. We do know that in pregnancy, yes, as Louann has mentioned, there's massive rises in the hormones that are particularly related to reproduction and lactation. But the impact on the brain in terms of what can happen afterwards in the disease states, yes, there is an impact of hormones on neuro-circuitry, and we mustn't talk about the two as if they're in isolation, they are there. But it's a mistake to generalise it, to say that all of the intellectual function, or in fact a significant amount of intellectual function is just thrown away, and that's where I part company. I agree with the aspects of the neuroendocrinology. We certainly have worked in the area of schizophrenia and found that when oestrogen is high schizophrenia improves but it does not mean that the disease brain state is the determining factor for how a woman should function.

JENNY BROCKIE: I find the tone of this very interesting because there's a kind of underlying fear amongst people about some of this stuff. Susan, there's a fear that I mean, are people looking away from what could be the science just because they're too scared to accept that these differences could be biological?

DR SUSAN MAUSHART: Well, look, that is the case in many instances, and I do object to that. I think we have to be absolutely fearless and ruthless in looking at the evidence. However, when Louann talks about maternal vigilance, to me that's primary carer vigilance. OK, it's not the mother who comes into the world hardwired to make sure that there are no sharp edges or electrical circuits where the kid can stick his finger,

JENNY BROCKIE: But Louann was saying, because of the hormone levels, this is what is driving women to behave that way.

DR SUSAN MAUSHART: My reading of the research is that, yes, women biologically start out with a slight edge. For instance, take the studies that I'm sure Louann is very familiar with about the ability of new mothers to sniff out their infant's T-shirt within, you know, minutes after they've given birth. They can smell their kid's undershirt, as opposed to 200 other kids' undershirts. Now, men can't do that at an hour after birth, and I'm sort of generalising here because I don't remember the specifics. But at two weeks after the child has been born, a father who has been involved and hands-on and changing the nappies and doing the night shifts and all that stuff can smell his kid's T-shirt. So what does that tell us?

JENNY BROCKIE: Mal, you're nodding your head. Why are you nodding your head?

MAL JAGO: I'm nodding my head because recently my wife and I have had a baby and I've been actively involved from day one, stayed in the hospital, the whole thing. I never had a feeling of wanting to have a baby or was not important to me. But like, bang, we're on. In terms of nurturing the baby and care and emotion, I feel just as much as she does and the baby has just as much dependence, the only thing I don't have are boobs – that's it. From the baby's point of view, there's no difference, and that's the only thing that I'm not providing that Mum can provide right now.

DR SUSAN MAUSHART: And you're not missing much, let me tell you.

JENNY BROCKIE: What do you think of Louann's theory about men and women's brains?

MAL JAGO: Everyone knows there's a difference. It's evolutionary between men and women and there's been men from Mars, men from Venus. We all sit there arguing over what the differences are between our emotions but I think we adapt and I think one of the big differences between man and other animals is that we have evolved and developed. And, you know, postwar, women are earning more money and men are able to actually get more involved and it's not about having to buy the house. Women can buy houses and men can go back to rearing the family as well.

PROFESSOR JAYASHRI KULKARNI: The question about are we scared to go down this track because we're going to somehow get ourselves into a situation where women get stereotyped as being completely run by their hormones and therefore useless for a certain amount of time every month and then useless after the age of 50, is scary. But what I think Louann has done, which is a good thing, is to bring this debate, to actually look at the impact of the brain issues in a hormonal and neuro-circuitry-wise, and I don't want to separate those two because the biology is not that well known that you can separate those two, because there is something in all of this, as we've all said. But we need to think of it as a possible therapeutic strategy, that if you do have the situation where somebody is dysfunctional in terms of memory as a result of peri-menopausal depression or peri-menopausal memory loss or whatever it is, that there's a possible other new approach to that by using hormonal modulation. So for me there's a plus and minus in this, that it is an issue but it's also a solution.

JENNY BROCKIE: Amanda, I wonder in general what you think about this nature/nurture argument. I mean, just instinctively from your own experience, you know, how much do you think we are innately what we are in terms of our differences as men and women and how much do you think we learn to be different?

SENATOR AMANDA VANSTONE: Look, I don't think you can draw a black and white line. I think this is an area that's very much grey. And I think in a sense part of the contribution tonight has revealed one of the problems we all face, and that is someone comes up with a proposition, as has happened tonight, and some people talk about it as either it's right or wrong, and I think that's a mistake. It's a contribution to the great conversation of life and there will be variations on the theme.

JENNY BROCKIE: But if there was to be a female brain of the kind Louann is proposing, how would we deal with that in the workplace?

SENATOR AMANDA VANSTONE: Well, I don't think we'd draw up a statute to do it. Well, I think it's common knowledge that we are different. Look, we've said it tonight, various members have – we are different – we know that.

JENNY BROCKIE: We have seen people get into trouble here, though. We had the president of Harvard in America get sacked because he said that men and women that men were better at maths and science than women were, and he lost his job as a result. Now Louann is arguing that there's probably something in that, that there are parts of the brain that men are better at those sorts of things than women are. Do you think that's…?

SENATOR AMANDA VANSTONE: It's not an end point or a black line that says you won't be any good at maths or science or you won't be any good at sharing your emotions. It's just that you start off with a brain that's biased one way or the other.

JENNY BROCKIE: Lesley, I wonder if you're being as absolutist as you claim Louann is by rejecting out of hand some of things she said?

PROFESSOR LESLEY ROGERS: No, I'm not because I think all of biology interacts with our environment and our environment affects our biology and our biology affects the way we behave, and the science is not the sorts of things Louann is saying. Science is… That is not the end of the story. Actually to understand development and how brains work we're just, as Marcello says, at the beginning of doing that, and it's much, much more complex than we often would like to accept and people want the quick fix and the quick answer that seemingly explains their behaviour, and that's where I think the danger lies.

JENNY BROCKIE: But haven't we gone too far the other way? We believed for years and years it was all about nurture, that there was nothing inherently..

PROFESSOR LESLEY ROGERS: We always believed that. Even feminism only scratched the surface of that for a brief period of time. I mean, these sorts of ideas are not new. They've been brought forward over a very long period of time and basically it really hasn't changed greatly. It's good things are changing.

JENNY BROCKIE: Louann, a final comment from you. Are you saying biology is destiny, that we are just destined to be what we are and that we are inherently different because of our brains being different?

DR LOUANN BRIZENDINE: The message of the book is that the biology is something very, very important for us to understand, and understand how, as someone in your audience said, we have a predisposition to behave in a certain way. We are born with female-type brain circuits or male-type brain circuits, important to know and honour the fact that we have a predisposition. There's a huge individual variation, of course, but that we have a predisposition to behave in a certain way.

JENNY BROCKIE: So that's a yes. That's essentially a yes. That's saying our biology to a large degree determines our destiny.

DR LOUANN BRIZENDINE: All of our behaviour, all of behaviour comes from the brain. There is no behaviour that does not come from the brain. So behaviour and the brain are the same.

JENNY BROCKIE: We are going to have to leave it there. I'm really sorry, but we are. We've run out of time and I'd like to thank Louann very much for joining us tonight. Thank you for your time. And, Milton Diamond, thank you for your time too in Honolulu, thank you very much for your time. Thanks to everybody here who joined us as well.


JENNY BROCKIE: Shaun Hoyt decided to test the theory on some bright young minds.