#410： The Male Brain
Episode Stats
Summary
In this episode of the Art of Manliness podcast, Dr. Leanne Brisendine argues that about 50% of the differences between men and women are rooted in our biology, beginning with how our respective brains form in utero.
Transcript
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brett mckay here and welcome to another edition of the art of manliness podcast there's an argument
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out there that gender differences are just the product of socialization implicitly and explicitly
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the argument goes culture tells men and women how men and women should behave my guest today
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argues that drivers of male and female behavior are a little more complex than that in fact about
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50 of the differences between men and women are rooted in our biology beginning with how our
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respective brains form in utero her name is louanne brisendine she's a neuropsychiatrist professor at
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the university of california san francisco and the author of two books the female brain and the male
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brain today we discuss the latter work and the trajectory of the male brain takes from prenatal
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life all the way through old age we begin our conversation discussing how a mega dose of
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testosterone in the womb wires a male brain differently from the female brain and how that
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influences how boys socialize and learn during childhood louanne then discusses how the male
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brain is restructured again with another mega dose of testosterone during puberty and the impact that
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has on a teen's behavior she then walks through what happens to the male brain when a male falls in love
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has kids and enters mature adulthood consider this podcast an intro guide to how your brain works
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assuming you're a dude listening to this though female listeners will also get insights on why the
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males in their lives act the way they do after the show's over check out the show notes at
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aom.is male brain luann brisendine welcome to the show thanks for having me bro so you published a
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book a few years back called the male brain which is this fun narrative scientific narrative of what
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happens to a male brain from fetus all the way to elderhood so there's a lot of you know discussion
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out there about the basis of gender and sex right is it biological is it cultural so what's your take
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is it all biological or does culture play a role in how men and women behave and think well you know
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there's been a big discussion for many years between psychologists and biologists and the psychologists
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look at culture and upbringing and the biologists tend to look at the biology the hormones the genetics
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of of everything that they look at but including gender and um if you ask a biologist what part is
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biology and what part is culture and upbringing biologists will tell you it's about 50 50 from their point
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of view and if you ask psychologists how they look at it which is culture and which is biology they will
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say you know it's about 50 50 so really there is no disagreement there may be disagreement in the
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details but but in the broad sense there's no disagreement that culture has a huge part if not
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50 to play in how our behavior is shaped by our culture how our behavior is shaped by our family of upbringing
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and our schooling etc etc because things that boys are quote-unquote encouraged and allowed to do
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uh versus things that girls are encouraged and allowed to do are somewhat different and girls and boys tend to
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um if you left to their own druthers they will actually sex segregate during grade school years um and enjoy
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playing with same sex more than they do playing with opposite sex and that seems to have something
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to do with just the actual interests that boys have in in things that make a lot of noise and explosions
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and um kind of the come on guys let's go get them kind of the team effort and fighting off the enemy
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girls will do that for a while with the boys but then they get kind of bored with that and they will
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they want to they will like to do more of the category of play called um role play um they like
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to play like you be the doctor i'll be the patient or you be the mommy i'll be the daddy and then um
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role play these uh roles that also are in relationship to the other more than kind of come on guys let's go
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get them so there's a it's a big difference um and that's just kind of a brief summary of a type of thing
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that boys will do that with girls maybe for you know one one play of you know 15 minutes and then
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they want to go off running with the boys come on guys let's go get them or what whatever they're
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doing that's more active so that is a stereotype but actually in um all of eleanor mackabee's studies
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um from kids ages about five to age nine ten eleven twelve they really prefer to play the games that
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the their same sex peers want to play so that's something that's noticed of course then things
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start to shift when the hormones of puberty start to blast in right well let's talk about the hormones
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like i like at the beginning of the book you talk about you kind of list this cast of characters
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so what are the hormones that influence both male and female brains so if we start from the very
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beginning brett on terms of like at the moment that the sperm meets the egg that sperm is carrying an
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x chromosome the baby will be girl caries of y will be boys alike right at that moment our our gender is
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set uh genetically and at about eight to ten weeks of fetal life the tiny testicles in the male fetus
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start to pump out huge amounts of testosterone already and they marinate the body and brain and change it
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into male in the girl there is no testosterone and so her system develops without testosterone and
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ends up being female at birth so by the time we're born our our um if everything goes according to plan
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we're either male or female and at birth um after from about one month to 12 months in a boy his testicles
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continue to pump out almost adult male levels of testosterone during that first year of life
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um and girls it's about from age one month to 22 months so her body start her ovaries are pumping out
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estrogen for those first two years of life and we call that phase of hormonal development infantile
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puberty because of these huge levels of their um sex determined hormones we don't really know much
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about infantile puberty in terms of what it's doing and how it's really developing uh brain and body
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circuitry but biologists continue to think that it's most likely to do with it's priming the whole
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fertility system in humans um and um other other animals do not have infantile puberty so that's
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something particular to us humans uh then of course we have that pause called the juvenile pause or
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in the vernacular it's called childhood childhood is a time when female hormones and male hormones from
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the ovaries or testicles are very very low level and basically females and males during childhood have
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about the same amount of estrogen testosterone as the opposite sex so that's a time of quiet hormones
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with very very low levels um until the ramping up of puberty and males at about nine years old
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nine to eleven years old their testicles start to respond to signals from the pituitary and brain that tell
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um the testosterone making cells to turn on and between ages of nine and fifteen males go from a very low
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level of testosterone up to a very up to um you know 200 times as much so you're up at the two three
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400 level by the time you're 13 or 14 at the time when the first wet dream happens and that basically is
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an indication that the system the male reproductive system is primed and ready to go okay let's talk
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about so you're born you go through this infantile puberty we're not exactly sure why or what's going
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on but there's an indication that there's some sort of structural reorganization going on the brain and
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the body priming it for that fertility period later on so let's talk about some of the differences that
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we see between boys and girls during childhood they have the same amount of hormones with testosterone
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estrogen but as you said there are differences you mentioned sort of the different ways that boys and
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girls socialize and play um what are some other differences like how between boys and girls
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during childhood well one of the things that researchers have found is that um they've had
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several studies where they'll take boys at age six seven they'll let them play together for 30 or 40
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minutes and then the observers kind of uh rank them according according to like who ended up being the
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alpha boy and all the way down um to the bottom of the group and that's kind of called establishing
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hierarchy and girls don't tend to do that and they have uh other types of of play and kind of um
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different types of aggression than boys do but it's a little bit harder to establish a real hierarchy like
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boys do very quickly if you bring those boys back together at about age 11 or 12 they haven't seen each
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other in years and years so they have a couple of studies where the boys basically re-establish the
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same hierarchy as they had at that younger age at six or seven which is kind of remarkable if you
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think about it the um so there's this hierarchical play that's different different in boys and girls
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um and they just they basically there is it's not clear whether that those boys just have more um
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more hormones more aggressivity more charisma or all of the above that end up being the leaders of
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the pack but there is a very kind of clear leadership hierarchy established in boys pretty quickly that's
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not the same in girls and how do boys say learn right different how do how do they interact with
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learning or paying attention that's different from girls i think that's a fast the learning difference
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between boys and girls is one that's of course had a lot of airplay and a lot of schools that are
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trying to address this because um an example is is math and they were basically the study looking and
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trying to have how to get girls to learn math more easily or more quickly or learn math more like boys
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learn math and in in the in the studies that were looking at that they basically discovered that the
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way the boys learn boys fidget and wiggle and and and when they're learning math they kind of they
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they they they wiggle and kind of actually embody if you will they embody uh the equations or they
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embody the concepts in some way um so if you can't they stopped asking the girls to sit still and have the
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girls start you know wiggling around and doing some of the same kind of embodiment movements that the
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boys were doing and show that actually the girls learned uh learned math much more quickly so that's
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that's an interesting study that a lot of people have made a lot of it we don't really we really
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still do not understand very well um i think that um the idea that you want to have um boys sitting
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still all the time in a classroom and you remember that one of the things is is that most teachers of
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elementary school age age kids are female by and large and so there's been a big emphasis on like
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you know the girls who can sit still and draw and write and be and be um not jumping up and out of
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their chairs all the time are are the students who get praised by the teachers the most and it's usually
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the boys who are being considered being disruptive etc so they're getting a lot of sort of negative
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feedback in the classroom about their lack of ability to sit still so people have started
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thinking well maybe this isn't such a great idea to have everybody sitting so still you need to let
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each kid but in particular boys need to be able to move around uh to learn better one of the
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interesting insights i got from your book was sort of the mood and emotions of boys and girls so
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traditionally males in most cultures are expected to be stoic females are allowed to be emotional but you
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highlight there's research that suggests that infant boys um even young you know young boys they tend to
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be more emotionally i don't know what's the word sensitive than girls like they they get upset more
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easily and take a little longer to calm or soothe yes so the the uh an interesting thing is it's a
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little bit of a reverse you know in adulthood but in the child in in little boys basically uh get their
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nervous system more jangled and are more and are more sensitive to many things than little girls
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and it takes them a little bit longer to calm down and to soothe them lots of moms you know certainly
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notice this and they just behave accordingly in terms of the soothing soothing of of little boys but
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it's interesting that their systems are wired to be um more reactive and more sensitive in in childhood
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in little kids than maybe we're talking about like under age five or six and i guess they learned how
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to that's where we kind of see the interplay of culture and biology the the culture expects them
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to be stoic so they learn how to tamp that down well you know the i think that the biggest the
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was the most well-known adage is boys don't cry or you know you know suck it up don't you know
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suck it up let's let's stop the crying there's no use in crying like act like a man right i mean
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especially and the fathers the fathers tend to be that the fathers tend to be the ones who carry
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that culture to the boys mothers won't mothers don't say that kind of thing to their boys if
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they don't say like you know stop that crying why don't you man up you know stop making it stop
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making like a baby i mean mothers don't tend to say that it's usually fathers who enforce that mandate
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upon their sons because you know they don't it it upsets the fathers to see that maybe their sons
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will be shunned because they're quote-unquote a cry baby and it makes the father feel look bad
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so you mentioned boys tend to socialize in teams they establish hierarchies they're interested in math
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they sort of embody that through you know physically sort of becoming the equation physically um what are
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some other differences i think you highlight that boys tend to be interested in things or objects and
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girls people so i think this the the idea that boys are interested in in things and especially in
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toys that move um even little they've done some studies in young primates then the males little
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male primates prefer uh toys that actually have wheels and move and um little girls will play out
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they're not they're not so particular as little boys are about things that move and things that are
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uh that are active so that the toy choice the toy choice in in boys and girls you know you might
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have one out of ten boys preferring more girls things and one out of ten girls preferring more
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boy toys so there's that it's important to realize that the male and female brain are more alike than
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different we are the same species after all so um there and there's huge amounts of overlap so we're
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just we're talking about some things that are quite quite quite amount of stereotype here right okay so we
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we've we've gone through childhood hormones are about the same between boys and girls but despite
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that similarity there are some differences that show up and i'm guessing i mean i know you said like
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they don't know why the differences they they it could be the the surge of testosterone that you
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received in the fetus and when you're an infant might play a role so somehow that you know remember
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from like eight weeks of gestation the testicles are working overtime to make testosterone so
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testosterone is a really is the really important sculptor the sculptor of manliness of manhood of
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of the male brain circuits of the male body you know testosterone kills off any of the female parts of the
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organs you know because we have we have both organs where we all have both both organs in us at some
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point and then testosterone kills off all of the uh the female organs like the tissue that would become
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a uterus or vagina that is killed off by testosterone and the male organs are stimulated so there's
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testosterone is quite a um uh a biological sculptor if you will of of the male model okay so it goes
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through that sculpting process uh in in utero shortly after birth but then there's another reconstruction
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that happens at puberty that we all know about um so we all know the the secondary i guess is that
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where the secondary sexual like what is that called yeah the secondary like the deeper voice hair you
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know mustache and beard and general hair all that stuff all the stuff that you start feeling awkward
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about right around 12 or 13 kids are embarrassed about yes yes i know we had we used to have a
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grandson and he would actually for a while he was he would talk to us on skype about various things
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as he was going into puberty he used to count the number of pubic hairs and report back to us about how
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many and then it was very noticeable though when he was counting at about 25 he stopped we didn't hear
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from him anymore on that count so it was yeah it was all it was all lots of fun and exciting the
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beginning and then all of a sudden it's like uh don't think this is too cool not cool anymore okay
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well let's talk about what happens in the brain because that's what the focus of your book is so what
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is going on in this sort of this reconstruction of the brain during the male brain during puberty
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so basically you can just imagine it's a tsunami of testosterone just starts to hit the male brain
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and it hits those areas that have been primed in his brain to do what's the the most important thing
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from a genetic perspective for a male to do is to go sow his seed right you um that's the idea is to get
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your get your dna into the next generation which requires seeking out fertile females and inseminating
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them so that that is kind of like the basic mission of the male and um it's it's important to realize
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that because that's just how a lot of the wiring that's all turned on during puberty which can be
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quite confusing to boys um i'm sure most guys i talked to remember this vividly and all of a sudden
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every pair of breasts that walk down the street and you know every every kind of uh uh buttocks or
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sexual innuendo is it's all all of a sudden just kind of blares out at you and um there's this
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i can remember i can remember my son when he at that age that he was he would i was interviewing i
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said like i'm writing part of this book and he was about 13 i said what what do guys your age say about
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you know when girls come to school in very skimpy clothes in the spring and summer and he says well
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mom pretty soon you just you feel like you can't take your eyes off them but and at first you feel
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like a perv and then you realize that all the other guys are thinking the same thing so so i think that
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boys go through this period where they're really doing what their biology tells them to biology and
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hormones tells them to do and yet they have a lot of of of awkward feelings about what that means
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about who they are but that's just you know a part of the unfolding of this process in early
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adolescence so besides the amplification of you know sex and what other behaviors does testosterone
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start to encourage or promote in boys so i think another fascinating area that um i think we don't
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know enough about yet that's very interesting is that the male facial features and the male looking at
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other faces um the testing of looking at faces and then while you're in a brain scanner if males start
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to look at faces that are happy they you know they'll report that they're happy but if then they start to
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report faces even that are what are called neutral faces and they they report them in adolescent boys they
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report them to be angry faces and of course a really angry face that reports angry but all of a sudden
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even neutral faces are starting to look a little angry to them so you know you as an adult you will
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say well they're kind of misreading that a little bit and the misreading of that is is because something
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is happening in their brain to be looking at other faces to see them as being a bit angry um that may be
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something to do with self-preservation that you know that's probably old old wiring in the male brain
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from you know the our most successful great great great great grandfathers you know were the ones who
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survived and the ones who didn't get killed off by somebody else and were able to you know procreate
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and have us be their offspring so it's really important to to know what ancestors the way they
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survived and what characteristics in the male brain allowed them to survive so we mentioned boys even as
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children uh are very hierarchical i imagine this only gets amplified during puberty yes it continues to
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play out um and i think that because boys different boys you know some boys reach their full height not
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until they're in their early 20s on the other end of the spectrum and some boys reach their full height
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at 13 or 14 and so um something about the rapidity of their growth and their muscles their height um
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certainly allows certain boys to be much more um uh to maybe change their place a little bit in the
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hierarchy but um the testosterone is making them much more uh noticing any microaggressions microaggressions
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from others um and i remember when my son first started driving you know 16 17 microaggressions from
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other drivers that i didn't even notice you know when i was in i had to be you know his uh co-pilot there
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for a while microaggressions from other drivers drove him crazy at that stage so but those kinds
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of things play out in the classroom they play out on the you know on the playground that play out in
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in their lives so that's that's part of the sort of uh hierarchical and just how boys start noticing
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uh and maybe what we call hyper-cathecting or hyper-noticing um and being vigilant about negativity or
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maybe angry intense of other people right so here's an interesting question that i was thinking
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about so you have all this testosterone coursing through boys at puberty um which testosterone is
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supposed to you know make you more ambitious have more drive take more risk yet you know high schools
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across the country teachers reporting at this period of time boys become very disengaged from school
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so what's going on there why is it that you know they have this this this milieu of hormones that's
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you know driving them to be the best so they can uh you know pass on their seeds sow their oats as you
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said but like they're disengaged from things like school or other aspects of life we know we don't
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entirely understand what that's about but that we what we do know so i'll tell you we know what's going
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on in the brain at that time that the brain is having a huge like the second what's called the second
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brain largest brain development in the human uh growth pattern is in teenage years and what's
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happening is if branches on a tree are just sprouting all through the brain i mean there's so many more
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connections than you'll eventually need so there's all this brain growth that's going on like mad
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probably related to growth hormone and a lot of other types of growth like so not only is the body
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growing that the brain is actually growing and it's overgrowing and um one of the one of the things
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that happens that a lot of uh schools are trying to address right now is that the sleep the wake cycle
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changes hugely the the going to sleep doesn't happen until later in the evening you know you don't get
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sleeping want to go to sleep till midnight maybe and then really you need more sleep at age 14 than you
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did at 10 you know most teenagers really need about between 10 and 12 hours sleep a night
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because of all this growth and brain growth that's going on and growth hormone is secreted at night
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time so you know it's a really important time for that so boys may be sitting in classrooms actually
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their brain is still asleep it hasn't woken up yet it probably won't wake up till four o'clock in the
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afternoon or something you know it's very there's a there's a there's what's happening in the brain under the
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hood if you look under the hood the apathy and just not being able to focus and pay attention and
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actually it's that thing is shifted whole a whole hour later in boys than in girls so girls go to
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sleep earlier and they can wake up earlier boys go to sleep later and that will reset itself to be
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matched between males and females at about age 30. Interesting and I was what if my what I understand
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about testosterone is that it also promotes dopamine production which is sort of the you know makes you
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want to do things and I guess if you have too much dopamine like you need more dopamine to like get
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motivated it's like boys might actually be bored right they need a lot of stimulation to get to get
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excited about something and I think that's one of the compelling parts of video games you know the the
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video games that are the singer shooter shooter games where you're basically just all you have to be
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all alert all the time in every moment to see who's coming from which side and you know that and I think
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that that's an example of things that really get boys attention gets their brains attention and
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honestly the stuff that's going on in the classroom cannot hold a candle to that it's so slow it's just
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so boring it's just like it's not getting their attention so you're right it's that they're it's not
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that they have attention deficit disorders it's that they're not interested in paying attention to how
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the how the material is presented so that's a big problem in our in you know in how and how we teach
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adolescence and you're right about wanting to do well wanting to be excellent wanting and being ambitious
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which all the testosterone you know makes huge amounts of dopamine in the brain and so there's lots
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of uh shall we say um seeking excitement so teen boys really want to seek excitement um sometimes to
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the exclusion of caution but there's no excitement in the classroom generally for most teen boys all
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right so the puberty the surge of testosterone reshapes the brain it's all it's priming it for
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you know fatherhood basically but let's talk about before fatherhood because he had a chapter about what
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happens to the male brain when a guy is in love so what what goes on when guy sees a girl falls head
00:27:05.660
over heels in love what's happening to his brain so you know if he's found someone that he feels
00:27:11.520
like is his his partner his match he's sexually attracted emotionally attracted and his whole
00:27:17.840
brain is like all of a sudden takes on every little bit of the things that she likes and how she is and
00:27:24.640
and he that we call it kind of an emerging of your two egos and that he kind of takes her into himself
00:27:30.760
in his own mind as as his love object and so he's um like they say head over heels he's head over heels
00:27:38.440
for her and um the dopamine is surging and the oxytocin the the love hormone starts to get going
00:27:46.820
because you know touching caressing kissing really releases lots of oxytocin in both male and female
00:27:52.200
brains so he has basically bonded with her and um it's almost some people describe it almost as being
00:27:59.960
uh psychotic because you have a whole different reality your reality is through the lens of her
00:28:05.880
everything everything has to do with her spending time with her what she likes uh etc etc so it's it's
00:28:13.680
quite um uh the whole male brain and body gets overtaken by love as the female does well i thought
00:28:21.180
it was interesting to you note that uh that men like there's like this sort of this idea that women
00:28:25.820
are more you know grow more attached and they're the more the quicker to fall in love but this research
00:28:30.620
shows that men actually fall in love faster than than women do and it's interesting because the
00:28:36.600
visual cortex you know that's that part of your brain that's back there at the you know at the base
00:28:40.780
of your skull right right on the top of your neck the visual cortex in males is very stimulated all the
00:28:46.600
time by testosterone and it's seeking out curvaceous females i mean and so if once he's found the one he's
00:28:54.620
he's he can have love at first sight much more easily yeah well and also so from a genetic
00:29:00.920
perspective from evolutionary sexual selection perspective uh there's this sort of idea that
00:29:05.860
the males of a species want to uh reproduce with as many females as possible because it increases the
00:29:11.840
chances of them spreading their seed but you highlight research that in some species and particularly in
00:29:16.820
humans that there is that but also there's some men or males who are predisposed to monogamy
00:29:23.740
what what happened what's going on there right so i think monogamy you know in our species there's a
00:29:29.620
wide variety between those males who tend to be primed to be to have many partners and those who are
00:29:36.240
primed to be monogamous and um uh i think it's also somewhat cultural um in that you know what what is
00:29:43.620
acceptable in your culture or not but there are so we think that that has to do something with both
00:29:49.880
testosterone level because the the varieties the testosterone level between 400 and a thousand
00:29:55.460
is a long range and that's adult males are in that range and males that are at the very top of that
00:30:02.660
uh testosterone range have a higher likelihood of being promiscuous and of having lots of mates
00:30:10.960
and those in the middle and in the lower end are tend have a greater tendency to be monogamous so
00:30:17.440
some of it may have to do with testosterone level some of it may have to do with culture
00:30:22.720
and some of it may have to do with that i talk about that vasoprestin receptor gene
00:30:27.540
in that there seem to be in the little prairie vole studies that we look at there's a vole that is
00:30:34.020
called the prairie vole and the males in that species are very monogamous they pair bond they take care of
00:30:41.600
the pups um and his cousin the montane vole is um just the opposite he's kind of a hit and run guy he's
00:30:50.380
very promiscuous and uh and inseminates many females doesn't do anything to take care of the pups
00:30:56.420
probably doesn't even know who his pups are so they're very different and they just they've discovered
00:31:00.560
that the vasopressin receptor gene which is another hormone in the brain in those um ones that are
00:31:07.280
monogamous are very a long receptor and the ones that are promiscuous are very short and humans have
00:31:13.640
that same kind of vasopressin receptor gene and in some males it's long and some males it's short
00:31:19.480
actually it's at 17 different lengths in humans so there's a very large range and some studies have
00:31:26.780
looked at that a big swedish study looked at that and found that the males that are have the longest
00:31:32.320
vasopressin receptor gene and would be hypothesized to be more monogamous actually have the
00:31:37.020
longest long-term marriages so there's something to do with genetics culture and and hormones all
00:31:44.300
wrapped up into that which i think that's just fascinating that we humans would have that type of
00:31:50.640
diversity and propensity that is really interesting okay so a guy falls in love all these hormones are
00:31:56.580
bathing his brain and his body to pair up with a female they do and a baby results right so when we
00:32:04.560
like what happens to a male the male brain when he he becomes a father so the fascinating thing about
00:32:11.540
the fatherhood hormones the testosterone drops by about 30 percent and then a hormone that we call
00:32:17.420
the parenting hormone both in males and females the prolactin hormone um in males goes up by about 25 or
00:32:24.920
30 so the males when they go into fatherhood it's not just the female body we know is changing like
00:32:32.240
mad she's going through pregnancy she has huge hormonal changes but it was a big discovery to find
00:32:37.060
out that the males have a whole fatherhood set of hormones which decreases their testosterone and
00:32:42.220
increases this parenting hormone called prolactin in males now prolactin you know the word pro
00:32:47.340
prolactin lactation means milk formation so not that males breastfeed and that is the hormone in
00:32:55.120
females that makes breast milk so we don't really know what that hormone prolactin is doing in males
00:33:01.220
but we think it probably has something to be doing with the the parenting hormone in males and does this
00:33:07.240
decrease in testosterone occur even before birth it starts to a little bit it starts to drop and then for
00:33:13.620
the first six months after birth um that's when it's noted to be um 30 percent down and then after
00:33:20.120
about six months it starts to climb back up to the the set point for that individual so interesting when
00:33:26.240
the infant is most in need of care from both parents um that testosterone level that might say
00:33:32.920
drive him some hypothesis says it might if it was still higher would drive him to maybe not stay as
00:33:38.420
close to home maybe drive him to seek out other partners and you know so um some of the thought
00:33:44.440
is it it basically decreases the sex drive in the male could it like couldn't the testosterone decrease
00:33:49.960
because like you're not sleeping right when i when i had my kid like for the first like six months
00:33:55.380
you'd like i hardly got any sleep and you know as you say testosterone most of it's produced you know
00:34:00.480
while you're asleep so maybe the kids crying keeping you up is reducing your testosterone so you stick
00:34:06.180
just be from total exhaustion which every parent i think the biggest deficit of every parent is sleep
00:34:12.300
please let me sleep right those babies they're decreasing your testosterone exactly they do the
00:34:17.540
babies decrease your testosterone so that you're correct so okay we've gone through puberty what
00:34:23.200
happens in adulthood is like you know from 30 to 50 do things kind of stay the same for men's
00:34:29.380
it's sort of a stable period so you know what the counterpart in females is you know females have
00:34:34.620
something called menopause at 50 where they just where their ovaries stop producing estrogen because
00:34:40.200
they've run out of eggs males never run out of sperm and so you guys continue to have production of sperm
00:34:47.040
and testosterone for your entire lives but it does decrease i think that the peak of male testosterone is
00:34:53.860
between the ages of 19 and 29 so that's when the sperm production is at its height and testosterone
00:35:00.220
production is at its height and then after about age 30 the um testosterone level starts to decrease
00:35:06.440
between like one and two or three percent per year so it just it goes down by about age 50 um males are
00:35:16.160
only producing about half of the testosterone that they produced at age like 25 i mean what happens to
00:35:24.580
the behavior because of that decrease in testosterone so about age 80 um the testosterone level has gone
00:35:30.900
down enough that i know that george bernard shaw always said oh yes thank goodness that i'm not being
00:35:36.540
driven by that anymore i think cicero said something like that too yeah so it's a it's a well-known
00:35:43.920
comment right of like men who have been sort of driven sexually all of their lives and that's not that
00:35:51.280
it's a negative thing but it's certainly something that sometimes it's not sometimes you wish that it
00:35:56.580
weren't there um and i think that so the what's called andropause is a gradual decline in testosterone
00:36:06.260
that's normal with male aging and um it's still plenty to to you know have to to have muscle strength
00:36:14.060
muscles and you know it's still plenty to have energy and some sex drive but not nearly the amount that
00:36:20.800
you had when you were 19 or 20 and i guess uh men start to mellow out a bit at this age as well
00:36:26.760
yeah and i think that that thing about seeing seeing others faces as being possibly aggressive and that
00:36:32.680
thing about being being more uh a sort of hair trigger to um you know i think the tendency to road
00:36:40.500
rage or the tendency to you know uh taking things wrong um and feeling aggressive about it that that
00:36:47.440
whole tendency uh starts to decrease yeah i mean it's something i when i've talked to my friends
00:36:52.580
for about the same age as me like 35 talking about the difference between our dads when we were kids
00:36:58.440
and then like them interacting with our our kids with their grandkids you know and i remember your
00:37:02.660
dads were sort of on edge right their work and like they're just kind of seem grumpy and you know
00:37:07.780
peevish right and then you know they're in their 60s and they just seem like a completely different
00:37:12.220
they're just like mellow and calm and just i know they seem like a happy puppy you know it's
00:37:17.840
very different and i think it's quite shocking to most all of us even the girls like to watch your
00:37:24.500
to watch your parents with your especially your fathers with your kids because you know they're just
00:37:29.840
like a big teddy bear yeah and i mean what do you think's happening so you you see a lot of men
00:37:34.700
older men these days starting to take trt testosterone replacement therapy i mean how is that going to
00:37:39.700
change things so you know so i'm kind of working on a new book called female brain 2.0 which is about
00:37:45.380
women age 50 to 100 plus and so a lot of the females i'm interviewing their husbands in their 50s are
00:37:52.800
taking testosterone replacement and uh it's quite interesting to talk with these this of course i'm
00:37:59.300
seeing it through the women's eyes and then talking of course to some of the men as well and
00:38:03.460
there's you probably see these ads on tv right that's called low do you have low t do you right
00:38:09.680
and so of course you have low t after the age of 50 or 60 it's supposed to be going down you're
00:38:16.180
supposed to becoming that big teddy bear grandpa you know that's that's the life stage you're
00:38:20.900
supposed to be at and indeed there are some men that medically um lose too much testosterone and
00:38:30.340
have such a little amount that they need to have a replacement but by and large medically
00:38:35.980
um this idea of low t would apply to every man going through his he's not going to have the
00:38:43.420
testosterone he had when he's 25 and um lots of men these days i think are finding it um i think maybe
00:38:51.320
it's also a very american phenomenon that you just don't you don't want to lose your edge right you
00:38:56.340
don't want to lose your edge and you don't want to lose your energy you don't want to lose your kind
00:39:00.880
of like um you know you're ambitious aggressive creative i mean whatever the edge is that you have
00:39:08.380
and so i think that it's kind of seeking the fountain of youth a bit that so your aunt the
00:39:14.700
answer to your question about what it's doing so the women i talk to are uh post-menopausal their
00:39:20.960
husbands are getting their testosterone injections and they know for the first two or three days
00:39:25.320
he's just going to want sex as much as possible at the age of 60 or 65 and they are really frankly
00:39:31.080
just not that interested it's not like they're never interested but not at that level so it does
00:39:38.240
cause some marital problems interesting and i mean i imagine too you know they're gonna if you take
00:39:43.380
you might lose that generative stage of your life right when you're old and you're kind of sealing up
00:39:48.380
your legacy like you might lose that because you're thinking you just have that edge again where you're
00:39:53.400
not the i don't know i guess nostalgic is the right word maybe i think the correct word you said
00:39:57.880
was generative there's that the word kind of generative in that you've reached a stage where
00:40:03.120
you may you may have done not everything you're going to have to do in your life but you've done
00:40:08.520
a huge amount already in your life and your and your your productivity and the things that you've
00:40:13.040
accomplished and um it's it's your turn to get to smell the roses a little bit but also to
00:40:19.660
kind of give back and mentor the younger generation so i think that that that urge to teach others and
00:40:27.720
become a mentor and become a wise wise elder um i think i think is a wonderful lovely thing for men
00:40:35.100
and if you're just completely putting your testosterone back up to where it was when you're 25
00:40:40.700
that you know you're creating a conflict in yourself between those two i agree with you i think it's it
00:40:47.360
becomes a conflict and um uh so you and i both have a you know i'm asking myself the question of
00:40:54.880
like okay i can see why they want to do that and they want to maintain their edge because there's a
00:41:00.940
feeling of the youth culture in our in the united states that if you aren't part of the youth culture
00:41:06.840
you're you're out of it you're you're cast off to the side so um you know i that that's something
00:41:13.200
that's it's it's something that every person goes through in their own change in identity and
00:41:19.760
development as we all get older and some people just aren't willing to let that happen i see a
00:41:25.520
future think piece in like the atlantic or something about this topic or something good i hope you write
00:41:30.580
it right well luann this has been a great conversation where can people go to learn more about your work
00:41:35.740
well they can go on either the male brain or the female brain i would say it's a fabulous place to start
00:41:41.500
because um as you noticed from the back of the book there's many many many um other articles that
00:41:47.120
it refers to and um they can just start to to pick all of those apart and do a deep dive into you know
00:41:56.040
what it means sort of biologically and emotionally to be male awesome well luann thank you so much your
00:42:00.860
time it's been an absolute pleasure likewise thank you for doing what you do we all appreciate your
00:42:05.540
giving voice to this this whole area of manliness thank you my guest it was dr luann brisendine she's
00:42:11.800
the author of the book the male brain it's available on amazon.com and bookstores everywhere you can
00:42:15.900
find out more information about her work on our show notes at aom.is male brain
00:42:20.660
well that wraps up another edition of the art of manliness podcast for more manly tips and advice
00:42:32.760
make sure to check out the art of manliness website at artofmanliness.com and if you enjoy
00:42:36.200
the podcast i've gotten something out of it i'd appreciate it if you take one minute to give
00:42:39.560
this review on itunes or stitcher it helps out a lot as always thank you for your continued support
00:42:44.040
until next time this is brett mckay telling you to stay manly