>> from our studios in new york city, this is "charlie rose." charlie: a look at gender identity and the biology of the brain. it is the subjective experience of their own gender. it may or may not correspond to the sex assigned at them at birth. it describes someone who feels his or her body and gender do not match. about 700,000 transgendered people live in the united states. one joins me today to share his experience.

he lived and worked as barbara until he changed his sex to mail. -- to male. also three guests i am pleased to have here. eric, what are we going to talk about? eric: gender identity and the biology of the brain. it shows how brain science can be an integrating influence in our life. biology of our own gender identity as we understand it you become more empathic and we can understand if all of a sudden at age eight, nine, or

10, a person says i am in the wrong body. we can sympathize with them. this is not an interesting topic, it is an on -- this is not only an interesting topic it is a -- topic. we were ahead of our time when we started talking about this. now, you cannot pick up an issue of the new york times or vanity fair without having a discussion on gender identity. charlie: 17 million people watched the diane sawyer interview. eric: we can talk about what the biological underpinnings are. when we speak about the underpinnings, we want to distinguish two different concepts. atomic all -- anatomical sex and gender identity. gender identity is the more

subtle complex image that is the sense of one's self. let's begin with anatomical sex. it is determined by our genes. genes arrange in chromosomes. we have 23 pairs of chromosomes. we get one pair from our father and one pair from our mother. the difference between the fathers and mothers contributionsthe sex chromosomes, they are profound. women are asked x and men are asked why --women are xx and men are xy. let's begin with the y chromosome and see how it determines the sex of the mail.

we are born with a gonad that can develop into testes or ovaries. if there is a y chromosome, it has a region that contains the gene that activates the differentiation of the undifferentiated gonad into the testes. if it is not there, you have xx you have a female gonad develop. let's look at the mail differentiation -- male differentiation first. if the testes matures as a result of the sex the terminating -- the sex the terminating region of y it is but to the level you have a puberty as an adult. that gives you the male body

form. if the region of y is not there, you have development of the ovary. that secretes estrogen and progesterone and that gives you the female body form and changes in the brain. these are important changes. that is the easy part. this is the anatomical part. the more elaborate part is gender identity. we brought together this group of people to talk about that. enben is a long-term colleague. he is a major scientist in my field. he is chairman of the department of stanford, a member of the national academy of science and a transgendered person.

he can tell us what it is like before, when he felt like he was in the wrong body and how he feels now. not only how he feels, but others can describe what it was like interacting with him as a woman and interacting with him as a man. you can help people make a decision as to whether or not they should go on with their idea that they are in the wrong body and need a transformation. he has adopted a european strategy and applied it in the united states. people can think through what they want to do. they can make the decision in a thoughtful fashion. the reason he wants to delay puberty once it forms, it is a more radical procedure than if you receive it before puberty.

in the male mouse, the representation of the female and in the female, the representation of the male. this is not a novel idea. not working with mice, working with people, suggested we are all bisexual. one aspect matures and the other remains. you pointed this out. there are female components in men and in females, there are male components even in adult life. we have a guest to is interested in how kids differ, boys and girls, in the games they play and how they interact with each other. she is interested in how hormonal levels -- in children.

janet is interested in seeing what are the differences in cognitive capabilities between men and women. her data suggests there is very little difference between them. as i have gotten to know janet better, that is incorrect. she majored in mathematics. i have come to the conclusion that women are superior in mathematics and engineering. i think we are in for a fantastic program. charlie: tell me about the experience you went through. what led up to your decision? how do you carry forward? charlie:eric:ben: i was only about four or

five years old when i had strong feelings that i felt like a boy. i was born as a girl, barbara. i played with boys, i preferred boys' toys. i wished i was in the cub scouts. i would dress up as an army man or football player. it seemed normal to me. i felt like a boy. in middle school, i started to feel more comfortable with this. i did not feel i should have breasts. i did not feel comfortable wearing dresses, makeup, jewelry. it became uncomfortable. when i got into high school, i started to be teased more by kids. i had a lot of confusion about my gender. i was ashamed by a. i never spoke to friends or family about it. i felt shamed and confused.

this is before the internet. there was not a lot of information about this. as i got into my 20's, i was doing well in my career and doing medical and research training. i was uncomfortableto think about suicide. i never attempted suicide, but i thought about it. this is a picture of me when i was barbara. i think i was 30 at that point and i was a bridesmaid. i remember vividly the agony i felt, the discomfort putting on that dress, wearing jewelry and makeup. i completed my training and began a job at stanford 20 years ago at age 40. two years into that, i developed

breast cancer. i was confused about my gender but i knew i did not like to have breasts. when the doctor had to do a mastectomy, to remove the cancer, i said, while you are there, take off the other breast. he was horrified by this. since the cancer runs in my family, he did agree to remove the other breast. i cannot tell you how therapeutic that was. i so relieved to have those breasts removed. it was a different response my mom had when she had her vasectomy. she felt it was a blow to her femininity. the doctor discussed reconstruction and i said there was no way you are putting those back on me.

about a year later, i was reading an article about the life of james green, a female to male transgender person. i realized there were other people that experienced the same sorts of gender confusion. i went to see don a pioneer at stanford. he ran a gender clinic. after they evaluated me, they told me they thought i was transgender and they offered me the possibility of changing my sex. that was the resistible and within weeks i decided to change sex. i already had the mastectomy's. i did not want to do the lower surgery. i began taking testosterone and you can see the effects it has taken on me. a surprising effect, it became

harder for me to cry. males to female report it is much easier to cry. the main experience i had, after i changed, it is hard to describe the relief i felt. a weight lifted off of my back. i never had another suicidal thought. at the time i decided to do this, i was very worried changing sex would alter -- would harm my career. all of my colleagues and friends were supportive. i have been fortunate to have my career continue and to have lots of wonderful students and so forth. the other thing i would like to say, the other surprise is that i found living as a man has

changed the way people react to me. an experience happened after i changed sex. i was invited to give a seminar about my experience. a friend told me after i gave the seminar, one of his colleagues was talking to him and he said ben's work is so much better than his sister's, barbara. that points out something we have lived life as both genders. we all share intense anger at the different way society treats women based on their gender. in general, we would say internal society with a man assumes they are competent until

proving otherwise. this creates unfair barriers for talented women. charlie: listening to that story, this may be typical in terms of someone who is questioning. what does this say about gender identity. >> i wish we knew more. i want to show you a powerful example of identical twins who one of the twins, and we have proven they are identical and born male.

one of them at age three started to say everything about being a girl. in fact, if there was any issue that came up, she turned it into an issue of gender. she did some of those things that we consider hallmarks like preferring to wear female underwear and pajamas, etc. and by the age of seven, the family decided with the help of a counselor to change her name to a female name and to have the child assume a female role. here is twin sister with twin brother at the age of just about nine to 10 years. so, they are in fourth grade. what i want to point out is if i switch all the attachments to them, the earrings, the

clothing, the hairstyle, the shoes, you could basically switch one for the other. the fact of the matter is that kids with their clothing on are virtually interchangeable pre-puberty. their hormonal levels are virtually at that point interchangeable. everything happens really at puberty. here they are at age 14. now, because it is so difficult to live in a gender different from your biologic sex, when you have the toxic effects of your genetically hormone driven puberty which would make twin sister looked exactly like twin brother. you can see that he looks still almost like a nine or 10-year-old and there is a good

reason for it. she has had her puberty suppressed. the next slide shows the level of sex hormones across the human lifespan. look at the blue line which is the male level of testosterone the hormone that ben was receiving and some of us make. but, during fetal life especially in the mid trimester, the level of testosterone in a fetus rises to a level close to the full adult range. then it falls and then there's another blip up after birth, a kind of second puberty. then things go completely dormant. if they did not go dormant, we would have a whole bunch of puberty looking fifth-graders running around because everything is suppressed. eric: when we are thinking about possible causes for transgender, ben and i spoke about this before, wouldn't it be possible there is some kind of aberration

in testosterone secretion during development or shortly thereafter? norman: it is certainly possible. it is a very dynamic stage. we still don't know what that second bump is after birth or what role it plays or whether boys are born without testes and show any differences because of that. the problem, eric, is that when we want to look at hormone we want to measure it. you cannot get it out of the brain. the other problem is sometimes it is not the hormone level that is important but the affinity of the receptor for them and it is very difficult to measure such things. eric: it is a very fascinating problem. to see what is the biological

underpinning of entity. it is so important because kids who were in the wrong sex, their incidence of suicide attempts is serious. norman: it is one of the highest risks of any. eric: it is something we need to understand. norman: in the puberty process this system reawakens again. the system that has been awakened in utero comes back in which hormones hitting the pituitary causes the release of other hormones that strike the ovary or testes and cause the release of testosterone of estrogen mainly. those produced the differences between the body of the male and female which is associated with puberty. so, we have been able to, since 1980, block the release of the

hormone from the hypothalamus to the pituitary. once you do that so far upstream, everything downstream goes down to zero. we have a record of this medication being completely successful in shutting them down until the appropriate time and also the fact it is completely reversible. look how revealing this is because the twin sister affirms the female identity and the puberty blocks two years to get more time for counseling without measure of body change. that is very important because if we are going to give her estrogen, that will have permanent effects. take a look at what will happen to her if she was not given the blockade. she would look exactly like twin brother. he is in early puberty, but so would she have been because they are identical. here are the twins at age 17. at age 14, just after that

picture was taken, she began estrogen. at the same time having her male hormones blocked. with that, our patients do not need breast surgery when they feminize because it is so effective. she is now entering junior year of high school in that picture. she is absolutely fabulous. this past october, the dutch reported the first follow-up of the patients -- 55 whose puberty was blocked and sex steroids were switched. the dutch group had surgery at 18 and which point their total uncomfortableness with their gender disappears. the dutch found that the kids

treated this way were psycho socially functioning as well or better than the non-group. the dutch gave me their protocol in 2006. we started using it in boston children's hospital at which time we were the only major medical center to do so, but we are not that many years since 2006 and over 40 programs now. so, it is now becoming standardized care. ♪

charlie: let me turn to catherine and talk about whether this is wired. catherine: as we've just heard from ben and norman, humans have a strong sense of their gender entity and this is a critical component to our individual identity as humans. in humans, males and females display clear differences in behaviors. mostly but not exclusively related to sexual and social behaviors. for example, males and females have a very distinct sexual and

aggressive displays and we see in the previous episode that mothers of females are maternal and males are attacking the pups. how are these differences established and maintained? the basic mechanisms in which the brain controls the gender specific behavior cannot be studied experimentally in humans. instead, my laboratory is using the mouse as a model system. mice display clear gender specific behaviors. the mechanisms by which the brain controls gender specific behavior in the mouse can be studied using all the model tools of modern neuroscience. scientifical behaviors particular sexual, aggressive and parental behavior, are extremely maintained across different animal species. that suggests the brain control of those behaviors is also very maintained.

in contrast, the signals that trigger these behaviors are usually extremely specific of a given species. for example, in the species of birds called the american flicker, there is only one sign that matters to trigger gender specific behavior and that is the black mustache on the face of the male. so, if you remove the black mustache from the face of the male, then the other males will attempt to copulate with the male because they will assume it is a female. if you paint a mustache on the face of a female, the other males will attack it because they will assume it is a male. i have a mustache, i'm a male. i don't, i'm a female. in contrast, we use a very specific set of factors called pheromones. humans are particularly sensitive to visual and auditory cues.

a fact that has been exploited very much by the pornography industry. once we know the signals that trigger gender specific behavior, we can look into the brain. how was the brain processing these signals and establishing these gender specific behaviors? as we have heard from norman, in young males, there is very important release of testosterone and this release of testosterone has been shown to be essential to masculinize the brain. in males, testosterone is essential to establishing and maintaining the very specific set of certain underlying male

specific behaviors. females organize their brand in a different way in order to control female specific behaviors. we have performed a number of genetic experiments that show that the situation is a little more complex. the experiment we did is actually very simple. we looked at thermo detection which is indicated by this little cross on the structure of the brain. this animal is insensitive to sex specific cues. when we look at their behavior we saw something surprising. in grey is female, in black is male. the female is mounting the male which is a very male specific sexual display.

this female is displaying the male specific behavior. this male strangely instead of attacking pups is now retreating an infant and bringing it to the nest the male has. this mouse is displaying female specific parental behavior. so, what do we learn? what we learned is that the brain of both males and females contain the right presentation of male and female behaviors. the male is repressed by pheromonal system. the female specific circuit is repressed.

what is happening is the repression of the opposite brain, opposite sex behavior circuit no longer exists and therefore the female is able to display both male specific behavior and female specific behavior. similarly, the male can display both female and male specific behavior. eric: i think this is so beautiful because it provides the way we can begin thinking and exploring transgender identity if we have the circuits. you can see how it can contribute to wanting to be another gender. i think this is very profound. catherine: exactly, as eric mentioned, this shows the brain of males and females are similar.

and specific hormonal and genetic regulation leads to the predominate but not exclusive display of the behaviors of given sex. this is extremely important because animals occasionally need to display the behavior of the other sex. we have seen in the previous episode that males are occasionally ok to display parental behaviors. in many species, females are using mounting as a sign of dominance. the brain has been shown to be bisexual in fish, in reptiles more recently and now in mice. we think this ability to have the both presentations of the male and female brain could be totally relevant to gender identity. charlie: let me turn to melissa and talk about defining gender identity and sexual orientation

and gender behavior. melissa: i study the role of testosterone and human development. we studied genetic conditions that cause people to have either higher or lower levels of testosterone during prenatal development than would otherwise be the case. from those people, evidence suggests testosterone in human also influences gender development, including gender identity. to start, it is useful to put this into context to expand our understanding of the dimensions of gender related behavior. we have talked about anatomical sex and gender identity which is our sense of self as male or female or something else. also, people have sexual orientation and this is separate to gender identity. it refers to our erotic interest in male, females, both or neither. finally, there is a third class

of peter called gender role behavior. these other characteristics that differ on the average. some of the biggest ones are seen in childhood toy preferences. the next image shows the sex difference in height and we are all familiar with this. males tend to be taller than females but there is some overlap. the males are the blue and the females are the orange. the overlap would be the people that you would not know their gender by knowing their height. the next image shows these gender differences in play, play with toys like vehicles or boys toys or dolls, are similar in size to the sex different height. finally, we see the gender difference in identifying with the male gender. we can see this gender difference is even bigger and there is almost no overlap between males and females, but there are some people who are in

the other distribution. these include people who want to change their gender. how does this come to be? we have talked about these sex differences in testosterone, some of which occur very early in life. this corresponds to a period very rapid brain development so it provides an opportunity for hormones to program the brain in ways that might have enduring influences across the lifespan including gender identification. the next image shows data about women who have had very high level of testosterone before birth. about 2% of women who had very high testosterone, in adulthood decide to live is men. it is hundreds of times more than would otherwise do so. this has increased many times over by being exposed to high

testosterone prenatally. the next image shows men. in this case xy individuals who are actually xy females because their cells cannot respond to testosterone. they have testes, they are producing testosterone, but because their sales cannot respond, they look like girls. almost 99.9% of them want to live as women. eric: it is so profound because although we don't know the vast majority of cases what causes the desire to change sex, here we find one concrete biological explanation. it is clearly a biological factor and with time we will be able to identify the significant number of other ones. i think having one example is good.

melissa: when i began this work, people thought these different interests in boys and girls were completely socially determined but it turns out these are altered by prenatal testosterone exposure. the next slide shows the toy choices of girls and boys in general versus those exposed to testosterone before birth. boys spent most of their time playing with toys like vehicles. girls spent most of their time playing with toys like dolls. the girls exposed to testosterone prenatally or in between. they spend about half their time playing with toys that boys normally choose and about 30% of their time playing with toys that girls normally choose. these are different dimensions of behavior. the influence on gender identity is less powerful, it appears

than the influence of testosterone on childhood play. that leaves a lot of unidentified factors that contribute to gender identity outcomes. finally, this is not just testosterone acting on the brain before birth, but also children who have high levels of testosterone engage in different behaviors and this has a feedback aspect on their brain developed. this becomes an increasing mechanism where their behavior is increasingly masculinized as they go through life. charlie: thank you. janet, talk about cognitive abilities and performance. janet: we have lots of stereotypes in our culture that there are gender differences and abilities. people believe that boys are better at math and girls and women are better at verbal skills and boys are better at spatial performance. what does the real data show?

we are at distributions for male and female performance, blue for male and orange for females. you see the most recent data shows that girls are tied with boys in mathematic performance. many people find this surprising but i have data for millions of people showing this. in regards to verbal performance, you can see there is a female advantage but it is tiny. you can hardly see it. these are very subtle, slight differences. for spatial performance, the difference is a little larger favoring males. i will show you one spatial performance that involves the ability to rotate three-dimensional objects. other kinds of spatial performance do not show this quite a larger difference. you need this spatial ability if

you need to be an engineer or architect or if you want navigate around new york city. we get this gender difference in spatial performance in the absence of the spatial curriculum in the school. we teach kids lots of verbal skills and mathematical skills. we don't teach them spatial skills. these are completely trainable. some school districts are getting the message and starting to institute these programs. if we want to do something to foster women getting into areas like engineering where they are very underrepresented, instituting a spatial curriculum might really do a lot to help. i also want to emphasize the importance of cultural context in shaping these gender differences. this is the percentage of phd's awarded to women in the u.s. by decade beginning in the 1890's. it turns out, i did not know

this, it turns out even in the 1890's, 11% of the phd's were going to women. you can see it inches up in the 1930's and the percentage plummets in the 1950's. only 5% of the phd's are going to limit. it has been inching up ever since. today, 31% of the phd's in mathematics are going to women. why didn't plummet in the 1950's? the men came home from the war and the women were delighted to see them. they went to the suburbs and had lots of babies. there is not one single biological force that causes women to be good enough to get a phd. it has much more to do with cultural context. it is findings like these that led me to propose the principle of gender similarities.

men and female are similar in most biological performances. you saw math performances which is stereotyped. there are performances for women in those careers. this map shows the gender similarity type is. we have the overlapping distributions. you can see there is huge overlap in which males and females are similar. let me look at psychological disorders because for some disorders we do get very lopsided gender ratios. on the left part of this graph you can see two disorders were many more men are affected. alcoholism and autism. the blue bar is the preponderance of males.

that is not to say we don't have women alcoholics or girls with autism, but it is a preponderance of males. on the right, you can see depression and the eating disorder of anorexia -- it is a preponderance of women shown in the orange bars. we do have these lopsided gender ratios. we wonder why those are. my research has been on gender differences and depression. the gender difference in depression is not present in childhood, but it begins to emerge between 15 and 16 years of age as you can see the orange bar is going up. it widens between 15 and 18 years of age. gender differences in depression emerges in adolescence. ♪

many factors may have to do it jeans. -- with genes. it may have to do with other factors such as the media's emphasis on hyper-skinny models. boys have the advantage because they add muscle. that is the way the models look. that may be a factor. there is plenty of pierce sexual harassment in the schools. ♪

charlie: let me go back to this idea of how society is responding because we know from the cover of "vanity fair," we know time magazine did a cover story which i am told is the second-biggest selling time magazine cover story that year with the one exception of the pope. transgender is right behind the pope. ben: it is unfortunate society often sees transgender to be a mental illness or an immoral choice.

transgender people are still denied basic human rights, often subject to violence. in some states, transgender people can still be fired just for being transgender. as we heard today, the brain has innate circuits that determine our gender identity. to be transgender is not a choice i made, but it is how i was born. i should mention something we have not really brought out yet, there is a broad spectrum of transgender people. some of them prefer not to change sex or even to be identified as male or female. for some of us, there is a compelling innate need to change sex. 40% of us attempt suicide. i think by helping transgender teens to avoid this agony, the dutch pioneers are great.

norman: the prepubertal child is in a state of exploration. this is not gender identity expression. this is almost always a gender role-play, which is normal for children. of children, who are fairly persistent in their cross gender play, but are prepubertal only

about 20% will be transgender. 80% are not going to be transgender. what i would say to parents is if your child is getting close to puberty, or worse, is already in, and is showing this kind of behavior, saying i am the wrong gender etc., then you need to get help for that child fast. that may be calling your pediatrician and asking for a gender specialist to meet with your child. a child who holds on to the belief that they are in the wrong body at the onset of puberty feels-like pinocchio becoming a donkey, and they may take their life. these are the kids who are the

real deal. >> in some cases, will we understood taking place in the brain was large in some cases and some cases was small. where do you put this in terms of understanding what is going on? eric: i think we are in the very early stages of understanding. this discussion points out there is a biology. it is a challenging problem. but, our understanding is very modest. we talked about this before. many times people have asked how long it will take until we have a satisfactory understanding of the brain. it will take a century. we have made a lot of progress in the last few years that we -- but we are a long way from

understanding the brain. catherine: gender identity is so essential to who we are and our ability to be happy. we have a duty to provide some kind of explanation. it is not all black and white. ben: differences are not disorders. i'm proud to be transgender. i think it has different brains drive innovations and perspectives. the real question is why society persists in insisting that male brains are better brains which we have heard tonight is definitely not the case. eric: one thing that is interesting to see is as you function in a way that you are comfortable with -- does it increase your creativity? ben: i released a lot of mental energy that was devoted to

confusion. i would say yes. i have felt much happier and productive as a person. charlie: what percentage of people go under anatomical change? norman: we are in a state of flux on an operation that could cost a lot of money. the reason i say that is because insurance companies are waking up to the idea that this is a medical condition. that it is entitled to be billable for surgical and medical aspects of their care can be covered by insurance. it is going to change everything. up until now, people had to save up to have the surgery. it starts from the top down. first, you have to not make it

as a mental illness. you have to define it as a physical problem which it is. hiding it as being gay was, what freed up people starting to see gay people is not having a psychiatric illness. it was having it removed from the manual of mental illnesses. we will see. the colleges that are self-insured, maybe even the college you went to, his paid by people. if i am going over to some of them and seeing them. charlie: i thank each of you very much for coming. there is enormous interest, as you can see in the publications, and also the conversation that is taking place. this subject was introduced in terms of a television program -- somebody came up to me and identified themselves as

transgender. but, they said that to me that the fact it has gained so much attention made all the difference in their life. they felt not so isolated and not so different. they felt like they had been identified so they can have an appreciation of where they stood and what their options were. what are we doing next time? eric: we will continue to discuss child development. what are the consequences of growing up under different circumstances? how does it affect the cognitive development of children and is it passed on from generation to generation? charlie: thank you. thank all of you. and thank you. we will see you next time. ♪

grexit it behind us some of the biggest successes in tecate strictly -- >> it behind some of the biggest successes in tech history. the venture capital firm has backed 170 now public companies, four of them worth more than $10 billion. joining me today david c and john lily. -- david