June 18, 2012

Sex and Gender: Different but the Same

A new line of biological research turns the model of the interaction between the brain, sex and gender upside down.

I have written quite extensively on the research on sex and gender on this blog, focusing on both the biological and socio-cultural factors that may or may not influence gender development.

What I have learned from all of this is (1) that gender roles and behavior are predominantly influenced by cultural factors, while (2) sex identity (the sense of being a man, a woman or neither) has a much stronger biological basis.

The story so far.

So far biological research on the interaction between the body, the brain, the embodied sex and gender expressions has been based on the idea that sex identity (the sense of self) is based in unique properties of the brain.

That is: Due to prenatal hormonal influences, the brains of men and women are different, and this makes them men or women, not only on the outside, but also -- to a more limited extent -- psychologically.

Secondly, natural scientists tend to believe that much of our gendered behavior is partly influenced by this core identity, in the sense that women are -- for instance -- more likely to express empathic traits and men analytic capabilities, on average and statistically speaking.

All serious researchers in this field accepts that much of our gendered behavior is heavily influenced by culture as well, though. I have so far seen only one study that tries to prove that women prefer pink for biological reasons. (God, that was a stupid study!!!)

I have become more and convinced that much of what we consider "natural" behavior gender wise, is indeed cultural.

Much of this is caused by the fact that I live in  a country where women are found in all types of work. The fact that women now dominates universities tells me that the old idea that women are less analytical than men makes little sense.

It is not that long ago that a woman who wanted to go to university would be diagnosed as a hysteric and sent to a sanatorium.

Why do not men and women differ more from each other?

The new radical approach to sex and gender does not ask what makes men and women behave differently.

These researchers ask the following questions: Given the fact that men and women differ significantly body wise (size, muscle strength, hormonal balance, sex organs, the ability to develop a fetus etc), why is their behavior so similar?

Yeah, you heard me! The biologcial mystery of the day is the equality of the sexes, not the fact that they are different.


In a recent issue of the New Scientist, Kayt Sukel uses bikes as an analogy.

If you compare a chunky mountain bike with a lightweight road bike, you will see that their different structure will influence the way their capabilities and the way they are used:

"To compensate for the mountain bike's greater resistance, you have to pedal harder to reach the same speed; one difference makes you introduce another to achieve the same output."

Hence the idea is that men and women behave the same, because their brains are different: "In brain terms, while certain circuits may be shaded pink or blue, that would not stop the output, or behavior, being a uniform purple."

The keyword is compensation

I know that a lot of people believe that men must be significantly more aggressive than men due to the production of testosterone. Men produces 20 times as much testosterone as women, and the hormone is known to generate aggression in many animals.

But sexist stereotypes aside, in my experience men are not t more aggressive than women. Men tend to act out physically instead of psychologically, that is true, but then again they have the body mass to get away with it. Women can be mad as hell, if the culture allows them to express such feelings. So how do you explain the discrepancy between their use of hormones?

Remember that here are two sides to hormones: production and reception. The amount of hormones you are able to put into action is just as important as the amount you produce. And since the brains of men and women have different ways of making use of hormones, the quantity only tells us so much.

Indeed, neuroscience is often criticized for putting too much weight on the very average differences between the sexes. As Sukel points out, there is more variability within each sex than between men and women as a whole.

de Vries

The first one to make people notice the so-called compensation theory was Geert de Vries. In the 1980s he found that there were small differences in behavior between male and female prairie voles as regards nursing behavior, in spite of the females having many more receptors in the brain for vasopressin, a brain signaling molecule that been linked to parental care.

Sukel points out that the female voles' maternal devotion was clearly triggered by the hormonal changes of pregnancy. So the males' brains seemed to be compensating for the lack of pregnancy hormones.

Reproduction with a cost

Margareth McCarthy at the University of Maryland School of Medicine puts it this way:

"Many of the sex differences we see in the brain are there to help males and females develop different reproductive strategies. Bu those differences also carry with them some constraints. Males have high testosterone, female have cycles of various hormones. And those hormones come with costs with the regards to behaviors outside reproduction."

Larry Cahill, a neuroscientist who researches human sex differences at the University of California, Irvine. has done a review of several brain-scanning studies. Many of them show differences in men and women that are not accompanied by differences in their performance.


The New Scientist notes that

"Cahill himself may have found evidence of compensatory circuits at work, involving the amygdalae, a pair of almond-shaped structures deep within the brain thought to be involved in the processing and memory of emotional reactions.

Cahill's group showed that even when the brain is at rest, amygdala activity is different in men and women (Neuroimage, vol 30, p 452).   

That made neuroscientists sit up and take notice, because most imaging studies require resting activity levels to be subtracted from levels seen during experimental tasks in order to reveal changes caused by the task.

Given these findings, important results may be going unseen because at the moment men and women's results tend not to be analysed separately.

Cahill thinks the difference in amygdala activity could be a compensatory mechanism to make up for differences in testosterone levels.

'There are instances where everyone agrees that there is no sex difference on the behavioural level. But that doesn't mean there isn't a sex difference in the brain,' he says. 'It remains possible that the equal behaviour was achieved in different ways.'"

Imperfect world

I believe the reason this way of thinking seems so strange is that most of us has an image of the human body as a perfectly balanced system developed by a master engineer, being that God or Mother Nature.

But if you look at this from an evolutionary perspective, it makes perfect sense for nature to keep a system that actually works, and then find ways around other problems that might be caused by this solution.


The New Scientist does not discuss compensatory theory and the development of sex identity.

Gert de Vries (the man mentioned above) has looked into the brains of transsexuals, however. He and his colleagues found  a region of the hypothalamus that is about 50 percent larger in men than in women, and almost 60 percent larger in men than in male-to-female transsexuals.

Those who have followed this blog will know that I have spent a lot of time on such research, but also on social science explaining how small the differences are in female and male behavior.

Indeed, the battle of our perception of sex and gender has in many ways become a battle between the natural sciences on the one hand and the social sciences and the humanities on the other. The first focus on biology, the other on culture and semiotics. The first focus on the differences, the other on the similarities between the sexes.

(It is a if-all-you-have-is-a-hammer-everything-becomes-a-nail kind of thing).

Due to my own gender dysphoria I am convinced that at least some transgender conditions, my own included, are anchored in biology.

But at the same time I see that most of the arguments used in both outside and inside transgender circles are based on cultural stereotypes that have no basis in reality  (like in the argument that true transsexuals are more adept at holding their handbags in a natural feminine way than perverted autogynephiliacs).

The nature/nurture puzzle

I must admit that I have found it very hard -- intellectually -- to reconcile my own in-the-bones conviction that I have a strong "inner woman" with the amazing similarity between men and women I see around me.

As soon as I think I have found a trait that seems uniquely male or female, up pops someone who proves me wrong. And because of this it is very hard to explain what this feeling of "being a woman" actually entails, even if it is persistent,  strong and real.

The compensatory theory may provide a solution to this puzzle.

Even if your organism tries to compensate for the sexual differences, the brains of men and women are not the same, which must have some repercussions on how we see the word and ourselves. This means that the gender dysphoria felt by both female and male bodies may indeed be caused by them having brains more similar to the opposite biological sex.

And even if the culturally defined rules for how men and women ought to behave have no root in biology, the need to be validated or affirmed as a member of your real sex might have. Because of this transgender will often seek to find an expression of their inner self by using the symbols found in the culture around them.

They simply want to be loved for who they are.


  1. Interesting research.

    I always like your well-balanced, open-minded approach, Jack.

    I personally respect scientific studies for their reliance upon evidence beyond what is derived from theoretical presuppositions. Of course there can be biases, but the scientific community is generally disciplined in upholding sound methodological principles.

    We all have our preferences in what we'd like to believe. It is good to study research - not just pointing to studies whose conclusions you like, while ignoring or rejecting those that don't - to see what might actually be the truth, whether or not that truth seems politically or philosophically progressive.

    Deborah xx

  2. Wise words, Deborah.

    Extremely interesting post, Jack. Brilliant. I could say this is one of the best post i've read here. Many things here make a lot of sense. I myself have been in process of research and finding out my own answers to crossdreaming. Many intuitions, many readings, few clear answers. I want to thank you for giving me some answers and keys to create myself my own ones.

    Even if I still disagree about the usage of the term "transgender" and "condition" (and the "inner woman" shorthand) I know you have your own good reasons to use them, which I respect but I don't share.

    I can't deny that dysphoria exists and that it is experienced by some in our community, the fact I never felt it doesn't mean it is not there. For the moment I have no a clear personal theory of what it is causing it but most of the people who follow your blog wants to find it out, including me, of course.

    To my opinion, only a multidisciplinary approach will explain something as complex as human sexuality, so those who despise natural or social sciences are making a terrible mistake.

    I am convinced that pretending to understand "crossdreaming" based on biased frameworks is useless, with this I mean, we need to understand human sexuality as a whole if we want to have a complete view of the issue. This is why i disagree about the usage of the term "transgender condition": gender is such an artificial term and reminds a lot of the societal binary expectations, which, by the way, don't reflect what happens in nature.

    Sex and "gender" are terms of amazing fludity in nature (it would seem that even challenging to the binary) that speaking of a "condition" is misleading.

    I really loved the mention of evolutionary perspective in your post.

    " it makes perfect sense for nature to keep a system that actually works, and then find ways around other problems that might be caused by this solution."

    I think this is absolutely brilliant.

    As you said, even if anatomically, our brains could work in terms of "blue" and "pink", the reality of human sexuality and gender is like a watercolor rich in purple shades.

    Why to pathologize some of those shades?

    Jack, I really admire your work and this last post has been amazingly brilliant, I agree with most of what u've said (with remarkable exceptions) but the label of "transgender" is making us a weak favor, and, in fact, it seems to be contributing to that endevour that some scientists are engaged in since XIX century: pathologizing everything that doesn't fit the binary.

    "And even if the culturally defined rules for how men and women ought to behave have no root in biology, the need to be validated or affirmed as a member of your real sex might have. Because of this transgender will often seek to find an expression of their inner self by using the symbols found in the culture around them."

    This is very interesting. What I wonder is what does it mean to "feel like a member of your real sex"? For you, what does it feel to be a woman, Jack? This is a very delicate question. In the context of that world where human sexuality and gender is a watercolor of purple shades, would't sex be just a term that matters concerning reproduction? if as u said, women and men behavior are so similar in the outside, (despite if our brains are mostly blue or pink inside) why someone would need to be totally pink or blue in the outside? doesn't it respond more to binary societal expectations than nature?

  3. A good friend of mine, who is a physician, answered to me once to the question if he really believes in the binary as a genuine cathegory from his perspective as a man of science: "during these years working with human beings as a matter of study, what i can say is that there are no big differences between men and women except those regarding reproductive functions."

    As a biological female, I can say, I am never conscious of what being a female means except those processes concerning reproduction, such as when I am experiencing PMS. I can feel the hormones working hard on me and screaming to me outloud "you are a woman!" That's nature hitting me hard and I feel helpless. Besides that, I coulnd't tell what being a woman feels like.

    I really don't think there's a thing men can do or feel that I cannot, except those regarding reproduction: experiencing erections and ejaculation. The rest are or personal traits falsely attributed to genders or just social constructions. As artificial as they can be.

    The biggest question for me is why I long to experience those biological processes (such as ejaculation and erections)and at the same time I really don't want to have a male body or being a male?

    Is nature calling for me? is this just a construction of an arousing idea?

    I wouldn't call the construction of the arousing ideas a "fetish", bc it sounds even worse: offensive, artificial, and it pathologizes the whole stuff even more than the term "transgender condition".

    But the fact is i have the intuition this process of production of arousing ideas is very essential to understand human sexuality and, in this case, crossdreaming. There's nothing wrong in this. This is not mocking the actual suffering of people with dysphoria. This production of ideas of arousal must be experienced by EVERY human being regardless sex, gender, condition. It must be product of being more than biological beings: we are thinking beings.

    But, as the suffering and anxiety associated to the "gay cathegory" (in the way Michael Foucalt conceived) it seems to me that societal binary expectations are causing more suffering, anxiety and misunderstading than nature itself.

    Why is this offensive to those experiencing dysphoria? ain't this liberating? ain't this giving as back the label of "normal"? Is it better to think we have a condition and that is our fate to suffer for being born in the wrong body?

    I apologize if my opinions offend, this is absolutely not my intention. It just MY opinion as wrong or as right it can be. as Deborah said, "We all have our preferences in what we'd like to believe".

    Warm greetings to everybody here and thanks to Jack for this amazing blog.


  4. P.S.1: Apologies for mistyping and the mistakes!

    P.S.2: I really don't believe crossdreaming stems from the complex masochism/trauma even if we can't deny in some cases it seems to play a very important role.

  5. @Ariadna

    Terms are difficult in a field challenging the basic terms of our culture and language, as they bring with them many connotations and presuppositions.

    In a blog, however, there are limits to many times I can repeat the same disclaimers, hence the shorthand.

    I realize that some crossdreamers do not identify as transgender, but I use a very wide definition of the term that goes far beyond those that are gender dysphoric and/or transsexual.

    For me and many others the term "transgender" is a social and political concept for a group of people that share common interests. It is not a medical diagnosis. "Transsexual," however, is a medical term for me.

    The word 'condition' is meant in a neutral way, not implying a mental disease. Maybe I should come up with another.

    "Transgender expressions" is too superficial, "transgender variants" sounds stilted, while "transgender syndrom" is too medical. I don't know.

    As regards the use of the term "inner woman" or "inner man", see the following relevant discussion going on over at Crossdream Life at the moment.

  6. So to the question of how it feels to be a woman:

    A common statement is that transgender male to female people cannot understand how to be a woman, as they are men. That sounds very common sensish, but the question itself negates the very possibility of a female mind in a male body.

    I normally answer that I have no way of understanding how men feel, and that is the God given truth. I truly don't!

    I can relate to them as one human being to another human being, but I cannot grok not to all the manly stuff I am supposed to like.

    (You probably understand the sexual sensations of a men much better than I do.)

    Moreover, I do not think Lady Gaga will understand how it is to be Hillary Clinton either, so your point of limiting the knowledge of sex to bodily functions is a good one.

    All references to personality traits, stereotypical interests and occupations, and sexual orientation are mote, as they are all shared by both men and women.

    In fact, had it not been for my own gender dysphoria, I would be convinced that the sense of being a woman or a man was the end result of social conditioning. In other words, I like blue because boys are taught to learn like blue.

    The fact that gender dysphoria exists, though, makes it hard for me to ignore the fact that there is something biological that underpins a sense of biological sex, (but not gender).

    It seems to me that this is in one way or the other associated with an internal body image (which do exist) and -- as this article points out -- hormone receptors.

    I am currently exploring the possibility that gender dysphoric M2Fs are suffering of some kind of testosterone poisoning, i.e. we are producing male quantities of testosterone. This is far too much for a brain more wired like a female. Giving anti-androgens to M2Fs is known to reduce the anxiety. But note, this is pure speculation from my side -- so far.

    As I noted in my Jungian series, instincts and archetypes are not defined by their content. Instincts does not have language, but they may lead to the production of language, symbols and meanings.

    This is why so many transwomen and transmen talk about cultural symbols or practices when they try to explain what it means to be a man or a woman: "I am more empathic and caring", "I love fast cars", "I hate rough and tumble play", "I was a tomboy".

    I can tell you such stories too, on how I hate the alpha male race, on how I always end up as the peace negotiator and the understanding listener, but that does not prove anything, as there are many men that feels that way without being gender dysphoric,

    Because of this I cannot tell you how it feels to be a woman. It is a basic feeling without words. But I could write pages about the pain and longings associated with gender dysphoria.

    Come to think of it, maybe I should.

  7. This is great stuff. It is hard to divide behaviour into a male to female dichotomy because I don't believe that is enough. In a 1993 article entitled: "The Five Sexes: Why male and female are not enough", Anne Fausto-Sterling argued that if the human species is to be divided into sexes, then at least five would be needed.

    There are humour intersex species that do not differentiate into typical male and female forms, but have up to five distinct genders.

    Also, have you seen the work done on digit ratio (I imagine that you probably have), and how it is an indication of prenatal androgen levels. I have a digit ratio signifying signifying low prenatal testosterone levels, and normal for an average female. I also had an inguinal malformity that I needed abdominal surgery to correct, and inguinal development is also caused by prenatal testosterone washes.

    In any case, I believe that humanity seems awfully difficult to cut into a single male and female dichotomy, because biologically it actually isn't that simple.

  8. Brains of women and men are the same as one can not tell if a brain belongs to a man or a woman when you look at it.

  9. They're actually not the same. Women's brains and men's brains are structurally different, and wired differently as well. Also, the brain is bio-electrical, and hormone, and chemical levels cause neurons to to fire. It is a gradual build up of pressure, which eventually forces neurons to fire when it reaches a certain level. Prenatal testosterone washes cause men's brain's neurons to fire more easily, predisposing them to analytical thinking. Women's neurons require more build up to fire, predisposing them to intuitive thinking. This isn't to say that women can't think as analytical as men, or that men can't think as intuitively as men. It is just stepping outside of their comfort zones when they do it. This also means that both sex have their perceptive blind spots, as men retain a sense of space, and check time against it, while women retain a sense of time, and check space against it.

  10. My therapist asked me this, and I was very worried because I seriously couldn't answer it. If there's no real difference between males and females other than basic physical differences, then why do you want to be the opposite sex?
    It must be about the physical differences, surely?
    M2F's, what do you gain by desiring female reproductive organs?
    You can't want to produce babies and I've never seen a mention of anyone desiring to milk, so it's not that part of reproduction! Then at a biological level that leaves sex, attraction and how easily you can write your name in snow!
    If it's about sex, why do want to experience sex as the opposite sex?
    For M2F's that could be a high sex drive that's not being fulfilled properly. Girls appear to have a much heightened experience of sex that maybe overly-horny males think would be enough to sate the experience they have.
    I think this ties in with the hormone discussions on this blog, testosterone reduction makes them less horny and easier to sate.
    If it's about attraction, then that would suggest it's about body image/self esteem.
    Are you the quiet ugly bloke in the corner?
    Is it just a matter of finding a partner who loves you and it will sort itself out?
    I think advertising has a lot to answer for with this. Maybe ads targeted at different sexes crosses over - e.g. moisturizer for men - even only a few years ago you'd be laughed out of the changing room, now it's perfectly acceptable - but they're only just beginning to market it for men. They'd best find a use for towels and tampons for gents!

    Also, just a note about that study on transsexual brain sizes. I did email the author at the time it came out, and he said
    - the sample size is too small to be conclusive
    - that it doesn't have any bearing on other types of the transgendered community
    - the area is too small to be measured externally (i.e. you can't tell what size it is unless you're dead on a pathologists' table). So don't too curious about yours!

  11. @Ariadna Azul
    I agree with its hard to determine what makes a man a man and a women a women. The fact of the matter is that emotions in both forms are possible though both sexes.And that they only thing that both sexes don't share is that of reproductive ability. And in many ways that that is one of the only things that separate the sexes biologically.In many other ways the rest is part of the culture that you are in. There are some that say women are weak and some that say men are strong and we know that the opposite is true as well, like in Norway for example. As for what it means to be a man i really can't say.I also think that it depends on which way you look at it, but i can't personally say how it feels to be a man.
    @Jack Molay
    Like you in many ways i don't really know how to relate to other guys other than in a few ways. I can relate to them as humans, but in the other ways i don't know if i can. Most men seem to feel a certain way and i really don't seem to feel that way.

  12. @Jack,
    I do think in your next post,you must explain the pains you yourself have undergone due to your gender-dysphoria. Rather than attempting to describe what being a woman is, you must use your own subjective experiences.

  13. Before anyone reads too much into these brain studies, it would be useful to read this blog on how to view their statistical significance.


    One question not asked or answered by the study or the blog article is: What is the effect on the brain of long term use of anti-androgens and female hormones? Could that contribute to TS's having "female" brain structures?

  14. @anonymous

    That is one very useful article. The conclusion is clear: It is impossible to identify one factor that can be used to sort women from men.

    This tells me that whatever it is that makes gender dysphoric people feel out of touch with their birth sex, it is probably caused by several interacting factors, genetic, epigenetic, hormonal and environmental.

    I have made a list of my writing on the science of sex here:


    @Perry Jonathan writes:

    "@Jack, I do think in your next post,you must explain the pains you yourself have undergone due to your gender-dysphoria."

    You are right about this. I realize now that many non-dysphoric crossdreamers find it hard to understand how it feels to be dysphoric. It is time to get personal. I will write a post about my own life story.


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