- Welcome to the Huberman Lab Podcast, where we discuss science
and science-based tools for everyday life. [upbeat music] I'm Andrew Huberman, and I'm a professor of
neurobiology and ophthalmology at Stanford School of Medicine. Today, we are going to
talk about the psychology and the biology of desire,
love and attachment. Today happens to be Valentine's day, 2022. However, the themes we
are going to discuss pertain to desire, love and
attachment on any given day. And indeed the mechanisms
we are going to discuss almost certainly were at
play thousands of years ago, hundreds of years ago, and no
doubt will still be at play in our minds, and in our
bodies, and in our psychologies for the decades, centuries and
thousands of years to come. Indeed today, I want to
focus on core mechanisms that lead individuals to
seek out other individuals with whom to mate with, with whom to have children with or not, with whom to enter short or long-term relationships with, and for perhaps to end those relationships or to seek relationships on
the side, so-called infidelity. I'm certainly not going
to encourage or discourage any of these behaviors. I'm simply going to cover the
peer-reviewed scientific data on all these aspects of
desire, love, and attachment. I'm going to discuss how our
childhood attachment styles, as they're called, influence
our adult attachment styles. Yes, you heard that right. How we attached or did not
attach to primary caregivers in our childhood has much
to do with how we attach or fail to attach to
romantic partners as adults, because the same neural circuits, the neurons and their
connections in the brain and body that underlie attachment
between infant and caregiver, between toddler and
parent or other caregiver, and during adolescence
and in our teenage years are repurposed for adult
romantic attachments. I know that might be a
little eerie to think about, but indeed that is true. Now the fortunate thing is that
regardless of our childhood attachment styles and
experiences, the neural circuits for desire, love and
attachment are quite plastic. They are amenable to
change in response to both what we think and what we
feel as well as what we do. However, all three aspects
that we're discussing today, desire, love and attachment are also strongly biologically driven. We're going to talk about
biological mechanisms such as hormones, biological mechanisms
such as neurochemicals, things like dopamine,
oxytocin and serotonin, and neural circuits, brain
areas, and indeed areas of the body that interact
with the brain that control whether or not we desire somebody or not, whether or not we lose
or increase our desire for somebody over time,
whether or not we fall in love, what love means, and whether
or not the relationships we form continue to include the elements of desire and love over time or not. In order to illustrate just
how powerfully our biology can shape our perception
of the attractiveness of other people, I want to
share with you the results of a couple of studies. Both studies explore how people rate other
people's attractiveness. And in both studies, the
major variable is that women are at different stages
of their menstrual cycle. Now in the first study, men
are rating the attractiveness of women according to
the smell of those women. Now they're not smelling them directly. They're smelling clothing
that women wore for a couple of days at different phases
of their menstrual cycle. And what they find is that men
will rate the odors of women as most attractive if those women wore those shirts, that clothing, in the pre-ovulatory phase
of their cycle, okay? So this is not to say that men
do not find women attractive at other stages of their cycle. It is to say that men find women's odors particularly attractive, if
those odors were worn by women that are in the pre-ovulatory phase of their menstrual cycle, okay? Now, there was also a study
that was done where women at different stages of
their menstrual cycle are rating the odors of men. And a similar but mirror
symmetric result was found such that women who are
in the pre-ovulatory phase of their menstrual cycle
will rate men's odors as more attractive than at
other stages of their cycle. So the simple way to put
this is that there seems to be something special
about the pre-ovulatory phase of a woman's menstrual cycle
that makes men rate them as more attractive during
that time and women rate men as more attractive during
that particular time as well. So this is a bidirectional effect. The way that the second study was done, where women are rating men was
not just to smell the odors of those men on t-shirts, they did that, but they correlated
that with whether or not the shirts were worn by men that were particularly
physically symmetrical. They actually had these
men divided into groups. It was more of a continuum rather, rated according to body
symmetry and face symmetry. And women preferred more symmetrical men when they were doing the preference test during the pre-ovulatory
phase of their cycle. So again, the point is
that that pre-ovulatory phase of the cycle seems to create a bidirectional mutual attractiveness. Now, also extremely
interesting is that this effect does really seem to have
something to do with ovulation. Because in both studies, they had women that were taking
oral contraception or not. And what they found was
if a woman is taking oral contraception, it prevented
that peak and perceived attractiveness by the men,
meaning men no longer perceived a woman to be more attractive at a particular phase of their cycle. And also women taking oral
contraception no longer preferred the odors of more symmetrical men during the pre-ovulatory
phase of their cycle. Now, I want to make sure
that it's especially clear that it is not the case that
oral contraception reduced the perception of a woman as attractive, that did not happen in these studies. It reduced the further
increase in a male's perception of her as attractive. And if women took oral contraception, it prevented them from
preferring more symmetrical men based on the odors of those men. Now I realize there are
a lot of variables here. We've got odors, we've got symmetry, we've got menstrual cycle,
pre-ovulatory, non pre-ovulatory. And we have whether or not people are taking contraception or not. But the basic finding is that
depending on where women are in their menstrual cycle,
influences both men's perception of them as attractive and
their perception of men as attractive and oral contraception
eliminates that effect. So I share with you those
data to illustrate that we often think that somebody
is attractive or not based on, I don't know, how they look, their skin, their hair, et cetera, but it also illustrates that
their odor is a powerful cue for some people more than others. Some of us tend to be more
factory driven than others. Although if you watched the
"Huberman Lab Podcast" episode that I did with Professor David Buss from the University of Texas, Austin, who's a luminary in the field
of evolutionary psychology and has studied mate choice and mate selection bias over decades, he's really one of the
founders of that field, he emphasized findings
that odor for many people is a maker or a deal breaker. Meaning, there are some people
that even if somebody has all the characteristics that
they're looking for in terms of kindness, and
attractiveness, and values, and other features that
would and should be of very high priority in selecting a mate, that if someone does not like
the way that person smells, their innate body odor
independent of colognes, and perfumes, and soaps, et cetera, that that's often a complete
and total deal breaker. I'm sure there are some of
you that can relate to that. And there's some of you
perhaps for which that is not the case, and you can't
even imagine that being such a powerful variable. And yet the data suggested
indeed it is a powerful variable for many people out there. Before we begin, I'd like to
emphasize that this podcast is separate from my teaching
and research roles at Stanford. It is however, part of
my desire and effort to bring zero cost to consumer
information about science and science-related tools
to the general public. In keeping with that theme, I'd like to thank the
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Inside Tracker's plans. Just use the code Huberman at checkout. Let's talk about desire,
love, and attachment. And of course, these are topics that grab tremendous interest. So it's worth us defining
our terms a little bit before going any further. Of course, we can have many
different kinds of loves. There's romantic love,
there's love of family, so-called familial love,
there's love of pets. We can even love objects, where we can feel as if we love objects. We can love certain activities. We can have friends that we
love and so on and so forth. The word love is used to encompass a lot of different types of relationships. Today, we are mainly going to
be focused on romantic love and the neural mechanisms
of romantic love. I want to acknowledge here at the outset that most of the studies of romantic love have focused on monogamous
heterosexual love. And also when we talk about
studies focused on desire, and attractiveness, and
attachment, that's also the case. And that simply reflects the
general bias of the literature over the last 50 to 100 years. It does, of course, not
rule out that similar or different mechanisms could be at play in non-monogamous relationships, in homosexual relationships, or in relationships of
any kind or variation. It's also worth us defining
our terms around desire. It can mean lust, it can mean the desire for long-term partnership. So we need to define our
terms and throughout I will do my best to very carefully
define what I mean by desire, what I mean by love, and
what I mean by attachment. The formal study of love,
and desire, and attachment goes back to the early 1900s. One of the classic studies
on this is entitled "Love and Desire." It was published in
1912 and really focused on two opposing themes within romance. One is love which in that paper
was really meant to include attachment and dependence
or interdependence between individuals, right? And the other end of the
spectrum being desire, or the sexual desire for another. And romance was meant to
encapsulate both those things, love and desire. And for much of the 1900s,
it was thought that love and desire were on opposing
ends or in a push pull. And it was the dynamic push and
pull between love and desire that one could define romance. And that actually led to
much of what's out there in the psychological literature. Today, we are going to explore
some neurobiological studies, some studies of the endocrine system, meaning the hormone system that actually support that general model. And I'll point you toward what
I think is a very useful book in thinking about how relationships
can both form and last over long periods of time
and how those relationships can include both desire
and interdependence. I'll also talk about some
studies that have really focused on why relationships
succeed and why they fail, and how that relates to whether
or not there is sufficient amounts of attachment and desire. So today we're going to
talk about the science and indeed you'll also get some tools. Those tools should be useful
to you, whether or not you happen to be in a relationship or not, whether or not you're seeking
a relationship or not. I'd like to begin with an anecdote. And this is not an anecdote about my relationship history, it's an anecdote about
my scientific history. When I started graduate school, the chairman of the department
I was in at the time said to me, "Most PhDs last
longer than most marriages." And indeed he was right. And also most marriages in
this country end in divorce. I think it's about 50% with a
slight skew toward more ending in divorce than persist
until death do them part. But nonetheless, it's about half, and most marriages end before
the eight-year period is up. Most PhDs take anywhere
from four to nine years. So there was a bit of a
smearing of averages there, but the point he was trying to make really landed home for me. It did not scare me out of relationships nor did it scare me out
of a PhD, obviously. What it did illustrate
was that there's something about our attachment machinery that can be very, very compelling, such that people take on
tremendous levels of commitment. I have to imagine that
most people enter marriages assuming that they're going
to stay in those marriages. I don't think most people
enter marriages thinking they're going to get divorced. But that if 50% of those
commitments end in divorce, there must also be mechanisms by which our attachments can break. And today we're going to
talk about both the forming of attachments and the
breaking of attachments, what can prevent those
breaks in attachments, and indeed what can
lead to re-attachments. There are biological
mechanisms to desire, love and attachment, that's abundantly clear. Now there's a robust and
very large literature in animal models. What I mean by that are field
studies and laboratory studies in primates of different kinds, such as macaque monkeys or bonobos. People have looked at
these sorts of things, believe it or not, in
ducks, in laboratory mice, in different types of birds, et cetera. And if you look at that literature,
you can essentially find biological examples in the
animal kingdom for just about any behavior that you can
easily map to human behavior. So for instance, there's
a species of animal called the prairie vole. In one portion of the United States, this prairie vole species is monogamous. They only mate with
one other prairie vole, only raise the young with
one other prairie vole for their entire life. And in another region
of the United States, the same species of animal, prairie vole, will mate with many individuals,
they're non-monogamous. And the major difference,
at least as far as we know between the prairie voles in one location and another location is
the levels of a molecule called vasopressin in the brain and body. Vasopressin is present in humans. It has numerous biological roles. It's responsible, for
instance, for controlling the amount of urine that you excrete, the amount of water that you retain, and for sexual desire,
as well as mate seeking. Levels of vasopressin in prairie voles are strongly determinant of
whether or not a prairie vole is going to be a monogamous
or non-monogamous. Why do I raise this? Well, I raise this because the
literature on prairie voles is quite beautiful and has
been discussed quite a lot in the popular press. You can look it up with an
easily, just Web Edge search. You'll find lots of
information about this, lots of news articles about this, and lots of interpretations
as to how vasopressin might be involved in similar or
different mechanisms in humans. Now, I don't have a problem with mapping animal studies to humans. I think there's certainly
a place for that. But if we just lean back
and look at the giant mass of studies in animals and
their mating behavior, and their mate selection behavior, you can essentially find
examples of anything. You can find examples of polygamy, you can find examples of
cheating, of infidelity, you can find examples of all
sorts of different behaviors that in your own mind, you
can map to human behavior. But it's really hard to make
the leap from animal models to humans in any kind of direct way. And so thankfully there's
been tremendous work done in the last mainly 20 years or so, looking at human mate selection, human desire, human love
and human attachment. So we're mainly going to
focus on those studies today, and where appropriate, we
will map those findings back to the findings in animals to
see if there's some universal truths or some universal principles about how the neural circuits and biological mechanisms work. But by and large, we're going
to focus on human studies today. So unless I say otherwise,
the data that I'm referring to today are entirely from human beings. So let's talk about attachment
and attachment styles. And this will offer you the opportunity to answer some important
questions for yourself, such as what is my, meaning, your attachment style in relationship? One of the most robust findings
in the field of psychology is this notion of attachment styles. And this was something that was discovered through a beautiful set
of studies that were done by Mary Ainsworth in the 1980s, in which she developed
a laboratory condition called the strange situation task. Now, the strange situation
task has been studied over and over again in different cultures, in different locations
throughout the world. And in preparing for this episode, I actually spoke to three
different psychologists. I spoke to a psychoanalyst, I spoke to a cognitive
behavioral psychologist, and I actually spoke to a
psychiatrist, excuse me, not a psychologist, but a
psychiatrist with a medical degree and asked, is the strange situation task and the various attachment
styles that emerge from that task, are those
still considered valid? And indeed all three of
them said if ever there was a literature in psychology
that is absolutely tamped down and has a firm basis in both
data and real world principles and real world examples, it's this notion of attachment styles. So what is the strange situation task? The strange situation
task involves a parent, typically a mother in the
studies that were done, but a parent or other
caregiver bringing their child, their actual child into a laboratory. And there's a room with a
stranger and the mother enters the room with the child and
there are some toys in the room. And typically the mother
and the stranger will talk. Obviously the stranger is
part of the experiment, is not just some random
person off the street. And the child is allowed
to move about the room. They can observe the mother interacting with the other person or not, they can play with toys or not, but then at some point the mother leaves. And then at some point later
designated by the experimenter, the mother comes back. And what is measured in these
studies is both how the child, the toddler reacts to the mother leaving, and how the child reacts
to the mother returning at the end of the experiment. And oftentimes this will have
two or three different phases where the mother will bring
the child in then leave, then come back in and leave. There are also studies in
which the behavior of the child with the stranger is also examined. So there are a lot of variations of this, but the basic findings are
that toddlers, children fall into four different
categories of attachment style. And that these attachment
styles can predict many features of adolescent, teen, young
adult, and even adult attachment styles, not
in strange situations of the sort that I just ascribed, but in romantic attachments. I should mention also that
attachment style is plastic, meaning it can change across the lifespan. So as I describe the results,
I describe the different attachment styles that are out there, and if any of those resonate
with you or bring to mind certain people in your life,
please do not assume that those attachment styles
are rigid and fixed for the entire lifespan. There are also terrific
data that indicate that through specific processes,
both psychological and some biological adjustments that people can change
their attachment style, and that indeed people who have
different attachment styles can change the attachment
styles of others. But just to make very
clear what the results of the study were, I want to
review what the four different attachment styles are,
and typically people fall into one group or another but not several. So the four patterns of
attachment that were revealed by these studies, again,
were revealed by examining the behavior of the child in
response to the mother leaving and the mother returning,
and the child's response to the stranger that is
in the room with them. The first style is the so-called
secure attachment style. In the nomenclature of this kind of study, these are the so-called B babies, as in the letter B, bulldog, B. Not for bulldogs, but just
to designate this category. The secure attachment style
is one in which the child will engage with the stranger,
with the experimenter while the parent is present in the room. But that when the parent,
typically it's a mother, but when the parent or
other caregiver leaves, the child does get visibly upset. They might whine, they might cry, they might even tantrum a bit. However, when the caregiver,
meaning the mother, or father, or other caregiver returns,
the child visibly expresses happiness that the caregiver
has returned, okay? So that's the hallmark of
the secure attachment style. And again, this is all pre-verbal. This is happening long
before the child can express how they feel with words. And the interpretation of
this is that the secure child feels confident that the
caregiver is available and will be responsive to their needs and their communications. So that when the child
whines and, or is distressed, the parent doesn't come
right back into the room. But at some point they do
and they seem to have a sense of trust that if the
parent or caregiver leaves that the parent will come back, and that they're happy that they do. These children are also
very good at exploring novel environments after
the parent is gone, and while the parent is there. And almost always, when
the parent is there, they will explore more broadly, literally in space,
they'll venture out further than they will when the parent is gone. They also tend to engage
with the caregiver in a way that's not immediately
and completely trusting, but that over time
seems to evolve from one in which they're kind of
suspicious of this person to one in which they're at
least somewhat trusting, okay? So these were the general contours of the secure attachment style. And fortunately, nowadays
there are physiological studies measuring things like
heart rate and breathing and other measures that
correlate with the subjective assessment of what these
children are feeling. Okay, so first category
is secure attached. The second category is a
so-called anxious-avoidant or insecurely attached, which
are the category A babies. The children with
anxious-avoidant insecure attachment patterns
generally tend to avoid or ignore the caregiver, all right? Meaning the parent, and
show very little emotion when the parent leaves or returns. So this is the reason
they call them avoidant or anxious-avoidant and kind of insecure. There isn't this happiness or
joy that the parent is back. They don't seem to express that. They do not exhibit
distress on separation. And they generally tend to
have some tendency to approach the caregiver when they return, but there doesn't seem to be
a general expression of joy. And again, physiological
measures support that as well. Things like changes in heart
rate tend to be less dramatic in the anxious-avoidant
insecure attachment style than in the secure attachment style. Okay, so that's the second one. The third category is the so-called anxious-ambivalent/resistant-insecure
category. Okay, I didn't name these categories. So you have to blame others
in this one instance. For everything else blame
me, but in this instance, you have to blame the psychologists that named this category. The anxious-ambivalent/resistant-insecure
category also called the C babies, for the letter C just as a categorization. The anxious-ambivalent,
resistant-insecure toddlers, really, show distress even before
separation from their mother or other caregiver. And they tend to be very
clingy and difficult to comfort when the caregiver returns, okay? So they're distressed even
before the mother leaves the room and they tend to be very clingy
and really hard to calm down when the mother returns. They tend to show either
what seems to be resentment in response to the parent's absence. We don't really know what they're feeling. Or some helpless passivity. And there's actually subcategorizations that the psychologists have
come up with, C one subtypes and C two subtypes. We don't have to get bogged down in that. But just know that there
isn't one absolute measure that says, oh, well, this person is anxious-ambivalent, resistant-insecure. They could be somewhat
passive, or they could be, seem somewhat angry at the caregiver. But the basic idea is that
before and after the separation, they are clingy and difficult to comfort. They just can't seem to
calm themselves down, and physiological measures
of heart rate and hormone measurements such as cortisol
also support that statement. And the third category of
attachment style is the so-called disorganized or disoriented
or D for the letter D babies. This is a categorization
that was added later to this strange situation task. That is a real hallmark of
developmental psychology studies. It was developed by Mary
Ainsworth, graduate student, Mary Maine, who I actually had
the great fortune of taking a course from and learning
from when I was a graduate student at Berkeley many years ago. And this fourth categorization
was controversial for a while, but now
is generally accepted. The key feature of the
disorganized, disoriented category is that the toddlers tend to be tense and they tend to encompass a
lot of odd physical postures. They tend to hunch their shoulders. They'll put their hands behind their neck. They'll cock their head to the side. For those of you listening, I'm doing this on the video version. It's not where you don't
have to go see that. But for those of you that
are watching this on video, they tend to constrain
their body size a bit and going to odd postures
that they normally wouldn't do anywhere else. So this is why it's
called the disorganized or disoriented category. It seems like these children
just don't really know how to react to a separation. And they just start to manifest
behaviors and emotional tones that aren't observed
in other situations. Okay, so we've got our four categories. I'll try and use the
shortest possible names for each category. We've got category one,
which is securely attached. We've got category two,
which is insecurely attached, also sometimes called anxious-avoidant. Then we've got category three, which is the resistant-insecure category, which is anxious-ambivalent. And then there's this fourth category, the disorganized, disoriented category where they're so-called D babies. Now, what's interesting about
this from the perspective of desire, love and attachment
is that the categorizations of children into one of these
four different categories as toddlers is strongly predictive
of their attachment style in romantic partnerships later in life. Which is to me both amazing and surprising and not surprising all at the same time. Amazing because it means
that, first of all, we are relatively
hardwired for attachment. I think that that's
incredible and beautiful, that we have designated
neurons, nerve cells and hormonal systems
that are there to ensure that we have some response
to a caregiver being there, or not being there, or
returning, or leaving, but also that the same neural
circuitries, the same hormonal responses are at least
in some way repurposed for entirely different types
of attachments later in life. So when we hear the psychologist
talk about how we formed a template early in life
based on experiences that were even pre-verbal
before we had language, and those templates are
superimposed on our relationships, or we should say, our later
relationships are superimposed on those templates, there
really is a basis for that. We now have neuroimaging studies
to support, for instance, the work of Allan Schore
from UCLA, showing that when a mother and child
interact, either through very soothing interactions,
like bottle feeding, or breastfeeding, or
singing to one's baby, or putting them to sleep,
that the brain of the child and the brain of the mother are entering a coordinated
state of relaxation. And it's not one
direction, mother to child, the child is also calming the mother. Typically these studies were
done with mothers again, sometimes with fathers,
but typically with mothers. And in addition to that, when
the mother or other caregiver acts very excited and raises their voice, or puts a lilt in their
voice, or widens their eyes, that the child will do the same. And again, there's a
bidirectional interaction in that case of excitement. And there's the release of
neurochemicals like dopamine into the bloodstream, whereas
in the relaxation scenario and the soothing scenario,
there's we know the release of things like serotonin and oxytocin. So the neural systems for
attachment and the neural systems for what we call autonomic
arousal for being alert and calm don't act in a vacuum. They are tethered to other
people in our environment. And of course we know this, right? We sometimes hear the statement, no one can make you feel anything. I've always had a little bit of a problem with that statement. I don't think I'm contradicting
anyone in particular, but you hear that a lot, no
one can make you feel anything. Indeed they can, right? A physical injury can
make you feel something. If somebody says something
that you very much like, it can make you feel something. And if somebody says something
that you very much dislike, it will make you feel something. So the idea that no one
can make us feel anything isn't actually true. Our nervous system is tethered to the nervous systems of others. And that is true from the very
earliest stages of our lives. And in this case, we're
talking about how our templates for attachment in romantic
relationships, how we find them, how we maintain them, and
indeed how we break them and reform them is based on a
template that was established through an entirely
different set of priorities, which was how we feel safe and
secure in novel environments, depending on whether or
not our primary caregiver is there or not. Neuroimaging supports that. When I say neuroimaging, I
mean, brain scan support that, measures of hormones in the
body and brain support that, measures of neurochemicals support that. There's simply no way around this truth, that we have a set of roadmaps
in our mind that are reused for entirely different
purposes later in life. That is vitally important to understand. Because if one is successful in forming romantic attachments, maintaining
them, et cetera, or not, does in fact reflect the earlier templates that you've created. But as I've mentioned
before, the good news is that these templates can shift over time. And one of the more powerful
ways to shift those templates over time is purely by the
knowledge that they exist, and the understanding that
those templates are malleable. They can change through the
process of neuroplasticity. Again, neuroplasticity is just a rewiring of nerve connection. That is very much present in childhood, but also very much present in adulthood. So if you're somebody who
you think falls into category one, two, three, or four,
or you know somebody, or involved with somebody
who falls into category one, two, three, and four, the mere knowledge of
that can be very useful. But you might ask, well, what
do I do with that knowledge? Well, fortunately, both
psychologists and biologists have started to leverage that
knowledge toward establishing better, more secure bonds in
adult romantic relationships. And there's a book that has
really tapped into this. I think it's the first book
that has really addressed this head on. And that book comes from
two Columbia professors. And title of the book is
"Attached: The New Science of Adult Attachment and How It Can
Help You Find and Keep Love." The authors of this book are
Amir Levine and Rachel Heller. Again, both of them are skilled
academics and researchers who have really taken the
literature that I described on the strange situation task and mapped it to adult attachment styles. And also they've mapped out
ways that they've observed in their clinical practice. And that is laboratory
supported for, for instance, people that have an anxious-ambivalent or what we were calling
insecure attachment style, or for people that fall into the disorganized or
disoriented attachment style, how they can modify that
attachment style in or out of relationships in order
to establish what I think everybody wants, which
is secure attachment. Why does everybody want that? Well, secure attachment
allows people to be both in relationship, or if they
choose to be on their own, or to be in relationship
but physically separated from somebody else, or
even emotionally separated from somebody else and maintain what we call a stable
autonomic equilibrium, the ability to remain calm, clearheaded. You might not like what's happening, but you're able to navigate
that with some sense of clarity and not excessive discomfort. So, is there a goal in all of this stuff about love, desire, and attachment? Indeed, there is. The secure attachment
style is the one that leads to the most stable and predictable
long-term relationships. Put differently, babies,
toddlers, adolescents, teens, and young adults that have
a secure attachment style are more likely to find and
form long-term relationships than are people in the other categories. But people in other categories
can learn and eventually migrate into the secure attachment style. And I think that book "Attached..." I have no affiliation to the
authors or the book itself, I should just mention that. "Attached: The New Science
of Adult Attachment and How It Can Help You
Find and Keep Love," really it sounds very pop psychology, yes, but it is really grounded in the research psychology literature. And there's also some
interesting biology there. Another point to make
about attachment styles is that it is possible. And some of you may be
familiar with circumstances whereby people who are securely attached, either because they grew
up in an environment where secure attachment was cultivated, or because they developed
that on their own, can also migrate out of the
securely attached category into insecurely attached,
or into avoidant types of attachment styles as
teens, or as young adults, or as adults at any age
or any stage of life, by virtue of being with
somebody who has a different, perhaps less adaptive
attachment style, right? What this means is that
if you have or you develop a secure attachment style,
it's vitally important to protect that attachment
style because it is possible to become anxiously attached, even if you grew up in a
stable attachment framework. And again, this can happen at any stage. So if you're interested
in attachment styles and how they influence
adult romantic attachments, and certainly if you are a
parent, I would encourage you to check out the book, "Attached." Again, it's quite good and I
think that it offers a number of actionable tools to both form and hold onto secure attachment styles. So I mentioned that the neural
circuits for child-parent or child-caregiver
attachment are repurposed for romantic attachment later in life. But what are these neural circuits? What do they do? I mean, it's so attractive, if you will, to think about a brain
area that controls love, or a brain area that controls desire, or a brain area that controls attachment, but it simply doesn't work that way. As I've talked about
before on this podcast and I will say again and
again because it will persist to be true long after I'm gone, is that no one brain area
can give rise to anything as complex as desire,
or love, or attachment. Instead, there are
multiple brain areas that through their coordinated action create a song that we call desire,
or a song that we call love, or a song that we call attachment. Not a literal song,
although there are songs about desire, love, and
attachment, of course, many songs, some good, some not so good. But rather different brain
areas being active in different sequences and with different
intensities can make us feel as if we are in the mode
that we call desire, or in the mode of love, or
in the mode of attachment. But beneath all of that is this element of autonomic arousal. And I want to focus on autonomic arousal just for a bit longer, because it really is one
of the three core elements by which we form and
maintain loving attachments, and by which we break loving attachments. The autonomic nervous system as the name suggests is automatic. In fact, that's what autonomic means. Now it's actually the
case that we can control our autonomic nervous system
to some degree or another. But the autonomic nervous
system controls things like digestion, our breathing,
whether or not we're conscious of that breathing or not. It controls things like how
alert we are or sleepy we are. And the autonomic nervous system, as I just briefly described earlier, is really something that we
come into the world with. It's hardwired, all
the elements are there. But through interactions with our parent, either soothing interactions,
or fun, playful interactions, or dare I say, scary interactions, our autonomic nervous
system gets tuned up. Meaning, we each develop a
tendency to either be more alert and anxious, or more calm, or
a balance of alert and calm. Now, of course, this
changes across each day and depending how tired
we are late in the day. If we've been awake for a while, we tend to get sleepy early in the day. If we're very rested, we tend to wake up and feel very alert. So the way to think about
the autonomic nervous system is it's kind of a seesaw. We go back and forth
between being very alert, we can be alert and calm, or
we can be very, very alert, we can be in a state of panic, we can be fast asleep so
we can be extremely calm, or we can just be sleepy, semi
calm but still also alert. So think about it like a seesaw. And that seesaw has a hinge, and that hinge defines how
tight or loose that seesaw is, how readily it can tilt back and forth. Our autonomic tone is
how tight that hinge is. And there are biological
mechanisms to explain this, but here I just want to
stay with the analogy of the seesaw for now. The interactions between child
and caregiver early in life take the child and the caregiver from one end of the seesaw to the other. From being very alert in a
state of play, for instance, to being nursed and being very
soothed until we go to sleep. And of course, we each have a seesaw, the parent and the child has a seesaw, and they're interacting. What do I mean by that? Well, there are beautiful
studies, and beautiful not in the sense that they
focused on a pleasant topic, but beautiful because they
were done so beautifully well, that looked at, for instance,
the response of mothers and their physiologies and
the response of children and their physiologies
during the bombing of cities during World War II. So an unpleasant situation. But what was revealed during
the course of these studies was that if the mothers were very stressed during an onslaught of
bombing of the city, the children's physiologies
tended to be stressed also, and persisted in being stressed
long after that stressful episode was done. They actually followed that these children well out from many decades afterwards. Conversely, if the parent,
and in this case, again, it was mothers that were
explored in these studies, had turned this whole business of going into the bomb shelters into
somewhat of a game, right? Taking it seriously, but
essentially telling the children, "Okay, it's time to go," but not expressing much
stress or distress, the children also didn't
develop much stress, or distress, or trauma. Now there were exceptions
to this, of course, but in general, that was the rule that the autonomic nervous
systems of children tend to mimic the autonomic nervous systems
of the primary caregiver. And the mechanisms by which
this occurs has been explored. And again I just refer to the
beautiful work of Allan Schore at University of California, Los Angeles. And again, his name is
Schore, spelled S-C-H-O-R-E. I'm looking down briefly at the floor here because I'll just reach for the book. He has a wonderful book called
"Right Brain Psychotherapy." It's a little bit technical, but if you're interested
in some of the studies, this book "Right Brain
Psychotherapy" details how everything from nursing of children
to playtime behavior, to strange situation type
task behavior that we talked about before which of
course occurs when children get dropped off at
daycare, or nursery school, or with babysitters, et cetera. And indeed all types of
caregiver-child interactions tune up that autonomic nervous system, so that the child ends up with
an autonomic nervous system that either tends to lean more
towards alert and anxious, or can be very alert but calm, or can be very calm and hard to budge. Again, it's the tightness of that hinge that really underlies
these attachment styles that we were talking about earlier, and not on this episode of
the "Huberman Lab Podcast," but on many other previous
previous episodes, such as the master stress episode, or some of the optimized health episodes. You can find these if you
want at hubermanlab.com. A lot of the tools and techniques
that are recommended there have to do with readjusting
the autonomic nervous system in deliberate ways as an adult. Again, I won't go into the specific tools, but for instance, the physiological sigh. This tool that I've talked
about extensively of two inhales through the nose, as deeply
as you can on the first one, sneaking in a little bit
more air on the second one, and then a long exhale through the mouth is a way of adjusting
that autonomic seesaw. It tends to make us more calm. It activates what we call
the parasympathetic arm of the autonomic nervous
system, which is just fancy nerd speak for it's a quick way
to calm yourself down, right? Things like ice baths, or cold
showers, or cold immersion, or deliberate
hyperventilation by contrast, or ways in which we can
deliberately increase the level of our so-called sympathetic
arm of our autonomic nervous system to make ourselves more alert. Why would you want to do that? Well, you can do that to be more alert, to be more awake, if you like, or as a form of self-induced
stress inoculation to be able to tolerate
higher levels of adrenaline by making it a practice
that you self-direct. The reason those tools are out
there is because many of us, for whatever reason, we
don't have to blame anyone, but because of our childhood templates, because of things that
happened and didn't happen in terms of our interactions
with caregivers, have autonomic nervous systems
that are tilted to one side or the other more than we would like. Or in which the hinge that I'm
talking about in this analogy is too loose or that is too tight. And we're stuck in a mode of anxiousness, or stuck in a mode of lack of energy. That's what those tools are really about. But at a deeper level, the
autonomic nervous system is really the system that
governs how we will react in response to a romantic
partner being present or leaving. And I don't necessarily mean
leaving the relationship entirely, although it
could mean that, right? We know people, I'm sure you
know people that upon the end of a relationship that
they wanted very much, are absolutely crushed. And actually in researching
this episode there, I discovered there's an
extensive literature finding that the feelings that one has
after a breakup are very much like a clinical depression in many cases. But there are individuals
that can look at a breakup as a transient event
that they don't interpret as going to mean so much for
all aspects of their life or reshaping their view
of themselves, why? Well, we have different
levels of autonomic function. And depending on where our
seesaw is, if you will, some of us become extremely
distraught and can't recalibrate ourselves, can't adjust ourselves
down from stress to calm, or can't take ourselves
from exhausted to more alert if we need to do that on our own. And so that's why tools
for doing that exist. But attachment itself is about where our autonomic
nervous system resides. So if I were to offer a set
of tools around these topics of desire, love and attachment,
I would say, first of all, you might want to think
about whether or not you fall into the secure, insecure,
or other attachment styles. Second, I think it is vitally
important for all of us, but certainly for people
that are in relationships or seeking relationships to
be able to at least have some recognition of where our
autonomic nervous system tends to reside both in terms of
when we are with somebody and when they leave. When we are apart for
long periods of time, can we calm ourselves? Can we self-soothe? Or are we very much dependent
on the presence of another in order to feel soothed? Now, I absolutely want to emphasize that there is nothing wrong. In fact, there's everything
right with feeling great in the presence of somebody else. That is actually a hallmark of strong and quality attachments. These days, we hear the
term codependent a lot. This was a, I believe,
the term was first coined by Pia Mellody. And it actually does occupy
an important role in the world of trauma, trauma healing,
so-called trauma bonding, topics of another episode. Actually, did an episode
on fear and trauma. And we will do one all
about trauma bonding with an expert at some
point in the future. But codependence and codependency,
the term can sometimes be misinterpreted as any
dependence on another isn't good. Interdependence, a
healthy interdependence, of course is good. It is the hallmark of healthy
child-parent relations, sibling relations and romantic relations. But a key element of healthy
interdependence is that, yes, our autonomic
nervous system is adjusted by the presence of another, but
that also that we can adjust our own autonomic nervous system, even in the absence of that person. That if the person goes away
temporarily or permanently, that we can still regulate our
own autonomic nervous system, both from states of
stress to states of calm, both from states of exhaustion
to states of more alertness. And of course, we all need sleep to go from exhaustion to alertness. But what I'm referring to here
is the ability to regulate when distraught, or
regulate when fatigued, or feeling depressed. And that is and is all about
the autonomic nervous system. So as we talk about attachment styles, and we talk about infant and toddler and adult attachment styles, what we are really talking
about is a complex set of neural circuitries. And one of those neural
circuitries, which is absolutely crucial is this autonomic nervous system. So if the autonomic nervous
system is one key component of desire, love and attachment,
what are the other two? And what I'm going to tell you
next is largely the pioneering work of Helen Fisher, who
is really an anthropologist, who's become a bit of a
neuroscientist and has collaborated with neuroscientists to
establish brain areas and neural circuits that are associated with different aspects of
attachment, love and desire. I think the first really
high quality study of neural circuits
associated with these themes was a paper published in 2005
in a very fine anatomical journal, perhaps the best
neural anatomical journal, which is the Journal of
Comparative Neurology. The Journal of Comparative
Neurology has been around for more than 100 years and
is considered the archival location for placing really
high quality anatomy. They have tremendously high standards. And the study that I'm
referring to is entitled, "Romantic Love: An fMRI," meaning functional
magnetic resonance imaging, "Study of a Neural
Mechanism for Mate Choice." And Dr. Fisher is a author on this paper as is Arthur Aron, and Lucy Brown. So all very fine researchers. And this study as well
as several other studies using magnetic resonance imaging, things like EEG, neuro
anatomical tracing, et cetera, have identified a large
number of brain areas that are associated with different aspects of desire, love, and attachment. And I'll just throw out a few
names of those brain areas and what they control. And then I'll tell you how those anchor to the other two categories
of neural circuits essential for desire,
love, and attachment. So not surprisingly the
dopamine system in the brain is associated with desire,
love, and attachment, and mainly with desire,
although to some extent, love. Dopamine is a neurochemical sometimes associated with reward. But as some of you have
heard me say before, it is mainly a molecule of
motivation, craving and pursuit. And that motivation, craving
and pursuit that relates to dopamine is not unique to
attachment, or love, or sex, or mating, et cetera. It is a universal generic
currency in the brain for pursuing something. Food when you're hungry,
a mate when you want one, to mate when you want to,
warmth when you're cold, et cetera, et cetera, okay? So it's not for one specific purpose. But the brain areas associated
with dopamine involve, for instance, the ventral tegmental area, the substantia nigra, areas of
that sort, the basal ganglia. You don't need to know these names, just understand that these
are networks of neurons that tend to have put the
person, you into a state of forward action and pursuit
and craving and motivation. They are not about being
quiescent, relaxed, et cetera. The neural circuits for
quiescence and relaxation are most associated with
love and attachment, not surprisingly, and
they're the neurochemical serotonin, and to some extent, oxytocin are the predominant
neurochemicals involved. And those are released from brain areas, such as the raphe nucleus
in the back of the brain. You may have heard that
the majority of serotonin in your body is made in your
gut, and indeed, that's true, but I hate to break it to
you, the serotonin in your gut is not responsible for your
feelings of love and attachment, at least not to a high degree. That's mainly going to be
the reflection of neurons in your brain that make serotonin. And there are other areas of
the brain that make serotonin as well and oxytocin as well, but they tend to be associated
with the warmth and calm, and the soothing that we feel
in the presence of another. And again, these are not
strictly divided circuits. We can have dopamine and
serotonin present in our brain and body at the same time to
equal or different degrees. And we return in a little bit
to what happens when levels of dopamine are very high and
levels of serotonin are low and vice versa and so on, including in states of
neurochemically modified states, as it were in, when we talk
about things like MDMA, so-called ecstasy. But in the meantime,
I want to just discuss the two neural circuits that use dopamine, that use serotonin and oxytocin, and that collaborate with
the autonomic nervous system to drive what we call
desire, love and attachment. And the three circuits are
autonomic nervous system, we talked about that one. Then there's the nervous system components or the neural circuits for
empathy, for being able to see and respond to indeed
match the emotional tone or the autonomic tone of another. And then there's the third category, and this might surprise some of you, it certainly surprised me, but the data point to the fact
that the third neural circuit that's very important
for establishing bonds is one associated with positive delusions. So given that the neural
circuits for empathy are absolutely crucial for falling in love and maintaining stable attachments, I'd like to talk about
those neural circuits and what they are. Now, often when we hear empathy, we think, oh, empathy is really about
listening to and really understanding what
somebody else is feeling. Maybe even feeling what they're feeling. And indeed that's the case,
but what do we mean by that? Right? What is it to
feel what another feels? Well, what it means is that their seesaw is driving your seesaw, or your seesaw is somehow
driving their seesaw. That there's a match in terms
of the tilt of those seesaws. Now it doesn't have to
be an exact match, right? If someone that you really he care about is very, very stressed, you
could also become very stressed. That's a form of empathic matching, and there are indeed
neural circuits for that. I'll describe what those neural
circuits are in a moment. But sometimes the best role
for us to take is actually one in which we are calm when
the person that we care about or that we are romantically involved with is very, very anxious. And in a few minutes, I'll
talk about how matching of emotional tone can be good or bad for the stability of a relationship, and complementarity of autonomic matching can be good or bad. In other words, sometimes it's
beneficial for a relationship to go into the same state as the other. And sometimes it's more
beneficial for us to not go into the same state as the other. But the important feature here
is that when we talk about emotional matching or empathy
or going into the same state or not going into the same
state, what we are really talking about is whether or not
the autonomic seesaw of one individual is
driving the autonomic seesaw of the other individual. And this is a vital principle
for how we fall in love and form attachments. And it's actually part of the desire and mating process itself. I would go so far as to say
that one of the prerequisites to the propagation and
expansion of our species is this notion of autonomic regulation. And to some extent, matching
of autonomic nervous systems. Let me explain what I mean. Last I checked, the only way
that new humans can be created is by way of sperm meeting
egg, either in body or in dish, but sperm meets egg and then
typically nine months later, we have a human baby. The process of bringing
sperm to egg, right? Mating behavior, sex behavior in humans is one of autonomic regulation. And what I mean by that is
the process of finding a mate, and in this case, I mean,
actually someone to mate with, typically, well,
scenarios vary, typically, is one of elevated autonomic arousal, meaning increased activation of the so-called
sympathetic nervous system. This is related to dopamine release and it's related to epinephrine release. There has to be a pursuit
or at least there has to be a mobilization to arrive
in the same location whereby one can mate, right? That almost always is the case. However, the sexual arousal itself in both males and females is actually driven primarily
by the parasympathetic arm of the autonomic nervous system. So while pursuit is one of
alertness and sympathetic drive, as we say, again, sympathy is not really what's at play here, the word simple means together, and the activation of the
autonomic nervous system toward more alert state is because of a
sympathetic nervous system, meaning the co-activation
together of many neurons in the brain and spinal cord. But then the actual
physiological arousal state that we call sexual
arousal is predominantly parasympathetically driven, okay? To be quite direct about this, if the sympathetic nervous
system activation is too high, the sexual arousal response
cannot happen in either males or in females, it's inhibited. However, the orgasm and
ejaculation response, which if you think about
it is required for sperm to meet egg is sympathetic driven. And then after orgasm and ejaculation, the parasympathetic nervousness
system kicks back in, and there's a calming and relaxation. So the arc of mating involves
sympathetic arousal, okay? Not sympathy, but alertness
and arousal for pursuit, then a tilt of the seesaw
at least to some degree for arousal of the sort
that we typically hear of sexual arousal. Then at the point of orgasm
and ejaculation is back to a sympathetic response. And how can I say that?
How do I know that? The sympathetic nervous
system meaning neurons within the sympathetic arm of
the autonomic nervous system are what drive ejaculation and orgasm. And then afterward there's a return to increased parasympathetic activation. And we don't know for
sure why that happens, but it's thought that in
species that pair bond, humans generally pair bond, not always, there the return to more
parasympathetic activation after orgasm and ejaculation
is thought to increase the exchange of pheromonal
orders, odors, excuse me, and to increase pillow
talk and pair bonding of different kinds, okay? So that's the seesaw going back
and forth is actually built into the process by which our
entire species propagates. So in some ways, every human
is required to navigate that process if they want
their offspring to persist. And of course, nowadays
there are technologies like in vitro fertilization,
intrauterine insemination, there are a variety of ways
that technology has allowed people to circumvent the
actual physical mating process in the way that I described. But by and large, that's
the way it it's done. And certainly that's the
way it was done historically for if not tens of thousands or hundreds of thousands of years. That process is also what happens in all mammalian species that mate. Okay, so I'm overlooking
an entire literature of animal studies that classic
studies of this were done by two individuals, I'll
just briefly mention them in case you want to
look at the literature. There's a guy at the
Rockefeller University named Donald Pfaff, P-F-A-F-F, who
has done beautiful studies identifying the neural circuitry, what's called the lordosis response. Unlike in humans, the
mating behavior of animals is rather stereotyped in
terms of the positions that they occupy. And the lordosis response is a U-shaping or a bending up of the hindquarters
of typically of rodents, but of other animals as well. The the male mounting is
almost always from behind except in some species of primates. And that lordosis response
is only going to occur during particular phases
of the estrous cycle. The estrous cycle is the
analog to the menstrual cycle, but it's not 28 days, it's four
days or some other duration in other animals, depending on the animal. The lordosis response is
strongly regulated by odors, by contact and is estrogen
and testosterone controlled. And then the male portion of
the mating sequence in animals, the mounting and thrusting and
ejaculation as they're called or mounting, thrusting,
intromission and ejaculation. Those are the four scientific categories that have been described, that's presence in
rodents and also in dogs where it was primarily
studied by Frank Beach, who was at University
of California, Berkeley for a long time. And the entire literature
around the neural circuitry for sexual mating behavior
in animals largely stemmed from the work of Donald
Pfaff and Frank Beach and their scientific offspring,
not their actual offspring. You can look at that
literature, if you like. There have been human neuroimaging
studies of the process that I described a few minutes
ago, believe it or not, of people in brain scanners,
not necessarily mating with other people, but going
through that arc of arousal, sympathetic activation
during orgasm or ejaculation and then the post-ejaculatory
or orgasmic phase in both men and women. And the brain areas associated with those have all been mapped out now. The spinal cord areas that
control things like erection, vaginal lubrication,
ejaculation and orgasm, those have also been mapped out. And this has all been
explored from the perspective of both basic science, just
to get an understanding of how our species has sexual
interactions and reproduces, but also from the
perspective of, for instance, trying to repair sexual function
after spinal cord injury, which is a prominent
concern for a lot of people, depending on where they have their injury, but in the number of people
that have spinal cord injuries. So this is both vital
biological and clinical data. The neural circuits for
everything that I just described reside in the autonomic nervous
system and are coordinated with the neural circuits that
are associated with empathy. The neural circuits for
empathy, again, there are many, but mainly two structures
that you should know about, the prefrontal cortex, which is how we perceive
things outside of us and make decisions on the
basis of those perceptions, how we organize those decisions, and an area of the brain
called the insula, I-N-S-U-L-A. The insula is a really interesting
brain area that allows us to interocept, to pay attention
to what's going on inside our body and to split some of
our attention, to exterocept. And the mating dance, whether
or not it's the dinner and date portion of the mating dance, or the actual physical dance
part of the main dance, or actual mating and sexual
behavior, kissing or otherwise, that is a coordinated
activity of two bodies, typically it's two. I realize sometimes it's
more, sometimes it's only one, but typically it's two bodies
at least in the framework we're using here. That coordinated dance is one in which the autonomic nervous
system of one individual in general is coordinating with
the autonomic nervous system of the other individual. And the insula is essentially
splitting one's attention between how we feel
ourselves, how our body feels, what we're thinking with the thinking and the bodily sensations of the other. And that can be communicated,
obviously, through words, it can be communicated through sounds, it can be communicated through touch, and it can be communicated
through a number of more subtle cues like
pupil size or whether or not, certainly in cases where
we recognize the person and we know their responses,
their autonomic responses under different conditions. We can assess, is the person comfortable? Are they uncomfortable? Are they more focused
on me or on themselves? This is the coordinated silent dance that if we look out in neurobiological terms, we can really see is all about
the autonomic nervous system, whether or not it's time to
tip the seesaw to one side or the other, depending on
whether or not the other person's seesaw is tilted higher
or lower than the other. Okay, so we have the
autonomic nervous system, and then we have this thing
that we're calling empathy, which is really about autonomic matching. And again, the insula
and the prefrontal cortex are neural circuits that are
crucial for autonomic matching, because they allow us to
say, what's out there, and do I want to match to it or not? Okay? And then the third
category of neural circuit that Helen Fisher and others
have found to be important for desire, love and attachment
is the neural circuit associated with self-delusion. What do we mean by that? Well, first of all, self-delusion
implies a kind of cynicism about love and attachment. And I think it was George
Bernard Shaw that said, "Love is really about overestimating the differences between individuals." Actually, when I hear
that, and as I say it, I really don't like that quote. I have no bone to pick
with George Bernard Shaw, but what it suggests and I
think what he meant was that, in love and attachment, we
tend to put so much value in the other that we forget
that many of the processes that are going on in our brain and body actually could be evoked
by many other people too. But I think it somewhat
overlooks the enormous power of attachment and the ways
in which somebody's smell, somebody's voice, somebody's everything, or somebody's particular
thing or things can really become so vital for our
autonomic nervous system to feel soothed and to
feel elated, et cetera. So I think that while
the quote is accurate, in the one sense, I think it does overlook the neural circuits for attachment and just how deeply wired
those can become for us. So I will balance that quote
with an enormous number of other quotes that I won't
mention, but that you can find out there that really point to
how incredible the person is that one tends to be attached
to that there's really only one or several people
that could ever exist that could evoke those feelings from us. And of course you can
read your Neruda poetry, and you can find these
things all over the place, in music, and poetry, and writing. So for every cynical quote
about these neural circuits being generic and could
be activated by anybody, I think you'll find an ample
number of opposing quotes that these neural circuits
can only be activated by that special someone,
or that particular person, or maybe in just a small
set of those people. So what of delusion? Well, the work of Helen Fisher
and others has really pointed to the fact that desire,
love and attachment are three separate phases of what we call romantic relationships. That typically, not always,
but typically desire tends to come first or falls in the early phase. That the process of
romantic/sexual interactions, it doesn't necessarily
have to be sex itself, but certainly something
that involves intimacy of some kind, right? And generally touch of some kind, eventually transitions
into what we call love, which eventually transitions
into what we call attachment. And I should just mention
touch because touch is a fundamental aspect
of this whole process. There's an article, a research
article, I should say, the title of it is, "Relationship-specific
Encoding of Social Touch in Somatosensory and Insular Cortices." Cortices being cortex. Cortex's plural, cortices. And again, there's our friend the insula. So this is a study that
explored what brain areas and what body areas are
activated by specific forms of attachment and social touch. And what they found not
surprisingly is that the areas of the brain that are
associated with touch, the somatosensory areas,
but more interestingly, the insular cortex are
strongly activated by touch. So touch in the amount of
touching, and proximity, and skin contact, not
surprisingly activates brain areas associated with somatosensory, touch, but also the insular cortex, which again, is this brain area that links the internal or feelings about what's
going on inside us and at the surface of our
skin with events external. And they found activation
of a number of brain areas, the amygdala, orbitofrontal
cortex, and so on and so on. That's not as essential
as just understanding that the insular is the place
in which we start to take our experience of our internal landscape, attach that to our perceptions
of the external landscape, and then assign that
a value or assign that some sort of interpretation. And positive delusion is
predictive of long-term attachment. What do we mean by positive delusion? Positive delusion is the contradiction of that George Bernard Shaw quote. It's the belief that only this person can make me feel this way. This other person holds the
capacity to make me feel this way physically or
emotionally or both. And so, as we move from
desire to love to attachment, our brain circuitry is literally
getting tuned up such that that individual that we
happen to be attached to, again, here thinking about
monogamous relationships, but I guess for non-monogamous
relationship individuals is and are the way in which
our autonomic nervous system can be regulated. They actually get access
to our control panel. So it's our autonomic
nervous system empathy and this positive delusion. Now positive delusion is critical. If you look at the stability
of relationships over time, something that's been extensively studied mainly by psychologists, but
now also by neurobiologists, what you find is that
there are some key features of interactions between
individuals that predict that a relationship will last. And those are many, but mainly fall under this
category of positive delusions. I'll return to those in what
those exactly look like. But there are also just a
handful of things that predict that a relationship will fail over time. This is largely the work of the Gottman's, is actually a husband and wife team up at the University of
Washington in Seattle. The Gottman's have, run a laboratory in the department of
psychology for a long time. They've also done a lot of public facing work around relationships. And they've talked about
the various aspects of relationships and
interactions between people that predict either staying
together or breaking up. So much so that they've
established a method by which they can look at video
interactions between couples and with very high degree
of certainty predict whether or not those
couples will stay together or break up over time. And they've identified what they call the four horsemen of relationships. These are things that essentially, almost always predict that
a couple will break up. And I think the current
number on this is that Gottman can predict divorce with 94% accuracy, which if you think about
is pretty remarkable. So even though these are
purely psychological studies, I'm not aware of any analysis
of underlying physiology, there are some things that they
can observe between couples that can lead them to predict
whether or not a couple will stay together or
break up with 94% accuracy. So what are those things? Those four behaviors, what
they call the Four Horsemen of the Apocalypse
[laughs] for relationships are one, criticism, two,
defensiveness, three, stonewalling, and four, contempt, with
contempt being the most powerful predictor of breaking up. Criticism, of course, does
not mean that there's no place for criticism in stable relationships. Of course, there is. Has to do with how
frequent and how intensely that criticism is voiced. Defensiveness, of
course, is defensiveness. We know as the lack of
ability to hear another or to adopt their stance. So lack of empathy, I think is one way to
interpret defensiveness. Stonewalling, which is
actually another form of lack of empathy. It's a turning off of this neural circuit that's so critical for
desire, love and attachment. The stonewalling essentially
means the emotional response or the request of another
is completely cut off. So it's, I don't think there's
been brain imaging of this, but I think, we can reasonably
imagine that it involves untethering your insular
response from the other and what they're dealing with, and focusing your insular response, [giggles] no pun intended,
on your own internal state or perhaps the state of
someone else entirely. I'll talk about infidelity in a moment. And then contempt. And contempt has actually been referred to as the sulfuric acid of relationship. I didn't say that, but
Gottman and colleagues have. That it is such a powerful predictor of divorce and breakups in the future. And contempt, of course, by
definition is the feeling that a person or thing
is beneath consideration, worthlessness or deserving scorn. And apparently they can
identify this in the videos of couples having
discussions and interacting by very elaborate eye rolls,
by expressions of anger in one individual when their
partner is actually expressing enthusiasm or excitement about something. It's the, oh yeah, you would say that, or deep seated resentment
toward the other, so much so that it's apparent
that one actively dislikes the other partner. So contempt, disregard for
something that should be taken into account is the other
way to think about it. That runs counter to all
of the neural circuits, all three of the neural circuits that we talked about before. It certainly, it is the
antithesis of empathy. It is anything but a positive delusion. It's really looking at
the other individual, either accurately or inaccurately as somebody that you despise. And then it is an absolute
inversion of the autonomic seesaw matching that I
was talking about before. It's a dissociating of your
seesaw from their seesaw. They're very excited about something, you're unexcited by it. In fact, it's an inversion of their seesaw where they're excited, you're down. They're down, you are up, okay? So it's basically an inversion
of all of the neural circuits that Helen Fisher and others
have identified as critical for desire, love, and attachment. And therefore it's not
surprising that it is so strongly predictive of breakups, and in the case of married
couples, of divorce. For those of you that are
interested in the work of the Gottman's and similar work, they've written several popular books. They're fairly easy to find. We can link to one of
those in the caption. But they've also developed some quite interesting online resources in their so-called Love Lab. I guess it's fortunate that
they didn't call it the Hate Lab or the Breakup Lab, 'cause they focused a lot
on what predicts breakups. But they've also written
extensively and researched extensively in peer-reviewed studies what makes people find
appropriate partners for them, and to maintain those
partnerships over time. So you can go, you can
search for Love Lab, University of Washington, Gottman, or any number of their various books. I think you'll find some
useful resources there. I want to shift back to
the work of Helen Fisher. She's made some very
interesting statements and some very interesting observations that at least to my mind map very well onto the knowledge of neural
circuitry both in humans and in non-human primates
and in other species. I realize that she's the
only name in the game. But she's made some observations
that I think are very, as we say, parsimonious, meaning
they allow us to organize a lot of this stuff into
some distinct frameworks. Now, she's also done some
really beautiful studies that involve data from millions
or even tens of millions of individuals on dating sites. So I'm going to share
those with you in a moment. But before I do that, I just
want to paraphrase Dr. Fisher, who said that sex drive
or desire that the pursuit of someone to mate with,
meaning to mate, the verb, not necessarily to find a mate, may be, she didn't say definitively,
but may be a way to forage for potential love partners
that the arc of this whole business is really the
order that we're describing it, that it's desire, then
love, and then attachment. And that oftentimes
people can get confused. You may know some of these people, you may be one of these individuals
who might confuse desire for attachment or might
confuse love for attachment, but that there's a sequence of recruitment of these neural circuits
that's established first from the pursuit of someone to mate with. And she's placed us in the
context of more modern dating themes where depending on
culture, people might explore several, maybe many,
many individuals before, quote, unquote, settling
down with somebody, at least for some period of time. I think that's an interesting framework because it circumvents a lot
of the, frankly, unanswerable questions about whether
or not humans were meant to be monogamous or whether
or not they weren't. Those are conversations
that hold cultural context, that hold all sorts of context, that really can't be addressed
in a laboratory setting. But this idea that sex
drive is a way to forage for potential love partners
and that love is a litmus test for whether or not longer
term or deeper attachments can and will form, is one that
at least makes sense to me. Later in the episode, we'll
talk about this notion of sex drive and desire. I'll actually talk about some
tools that have very strong data really to support them
in terms of things that people can do or take to increase
libido, both men and women, because there's actually
quite good data on that now. But in the meantime, I want
to talk about some of the work that Dr. Fisher has done in terms of categorizing people into... Again, we have four groups. These are distinct from the A, B, C, and D attachment styles described earlier. Although as I describe them, you might be able to map
them somewhat onto those. And these four groups are
groups that were defined through her studies of
people that were, or are, I don't know if they were or
if they are still on match.com, but a very extensive dataset. So again, millions if not tens
of millions of individuals. The number I heard her quote, and forgive me if this is not accurate, is that in upwards of
40 million individuals, in terms of whether or
not their neurochemical and hormone systems are tuned toward particular types of behaviors. What do I mean by that? Well, both men and
women, males and females have both testosterone and estrogen. Typically, again, these
are averages, but typically men have more testosterone
than they do estrogen, and they have more
testosterone than do women, and less estrogen then do women. Typically women have more estrogen than they do testosterone,
again, averages. And they have less testosterone than men, more estrogen than men,
and so on and so forth. But both hormone systems are active in both sets of individuals. And of course, all
humans, as far as we know, manufacture both dopamine and serotonin. Dopamine, as I mentioned
earlier, has a number of effects in the brain and body. But one of the primary
effects is that it places us into states of motivation and
pursuit for various things. There is somewhat close
relationship between the dopamine system and the testosterone
system in the hypothalamus, this brain area above
the roof of your mouth. And the pituitary gland,
which is responsible for making hormones that make
the ovaries and or testes, secrete testosterone or estrogen. So there's a lot of signaling
that occurs such that dopamine and testosterone tend to
operate as close cousins in a system of pursuit. And conversely, the serotonin
system tends to on average collaborate with the estrogen
system to impart certain physiological functions and behaviors. So these aren't hard and fast,
or I guess better stated, these aren't strict black
and white categorizations, but I think those general themes hold when you look at the
animal and human data. So Dr. Fisher has taken some
liberties, but I think they are what I would call logically,
and scientifically, and neurobiologically grounded liberties in classifying individuals
who are on these dating sites according to the types
of things they report about themselves and the
type of people they tend to match with on these dating sites, and created these four categories. The four categories are, she calls one, the dopamine category. So these are people who
would have high dopamine. And again, that's just a name. It doesn't mean they
have low anything else, but they are high on the dopamine scale. People who rate high on the
dopamine scale tend to be what the scientists and psychologists call high sensation seeking, novel seeking. They like new things,
they like spontaneity, they tend to be very adventurous. And I think that's largely true. If you look at the conditions where dopamine is super physiological, it's elevated beyond abnormal levels. Things like mania or when
people take certain drugs of abuse, like cocaine or amphetamine that really raise dopamine
levels up very, very high. For some period of time,
they do tend to increase energy motivation and novelty seeking. And of course, drugs like
amphetamine and cocaine have all sorts of deleterious effects that I don't need to go into here, but it's worth pointing out. But they don't tend to make
people calm and relaxed and seek soothing interactions. Conversely, the group
that Dr. Fisher calls the serotonin group
tend to be more grounded in soothing activities,
quiescent type activities. They actually tend to be, on average, they tend to like rules and follow rules, they tend to be homebodies,
this sort of thing. They're really, you can
imagine them this stable types, but they really like stability. They're not really into
spontaneity as much, again, averages. And then she created two other categories, the testosterone category
of high testosterone. This again, could be males or females. And then the estrogen category, again, could be males or females. And she gave these different names that I won't go into here. You can look up her work online, but she names like the
director, and the follower, and things like that. But I don't really want to use
those as much as I want to stick to the biological terms. So we have dopamine, serotonin,
testosterone, and estrogen. Now that might seem like an
unfair overgeneralization, but what's interesting is
not necessarily the name or the neurochemical system, right? Those could have just been
called category one, two, three and four for all that matters here. What is interesting is seeing
how those different groups of individuals that she
absolutely can categorize based on their self-reported preferences about behaviors and certain
kinds of interactions. How those groups tend
to pair up with people in the same or opposite categories. So what her studies reveal
is that people that fall into the high sensation
seeking, novelty seeking, spontaneity category,
the one that she calls the high dopamine category
tend to pair up with, at least in the short term, tend
to pair up with people who are also in that
dopaminergic category. So these would be people
that would spontaneously take a trip or explore
something new or new restaurant. They tend to be creative
and explorative types. So that group on average
tends to date and mate, and potentially form long-term relationships within category. Again, averages. Individuals that she placed
into the serotonin group or what she hypothesized would
be a high serotonin group, again, they didn't measure serotonin, but people that tend to place
value on stability, on rules, on certain forms of
traditional organization at home and in relationships, those people also tended to
pair up with select date, we presume mate with and
form stable relationships with people in the same category. Now, individuals in the
other two categories, the high testosterone group, and again, testosterone wasn't measured, but she called it the
high testosterone group, but these are people that
tend to be very directive, they tend to know what they
want and are comfortable telling other people what they want. And from them, these are
individuals that in her studies and in other studies tend to
be a little bit challenging, meaning they not necessarily
challenging to be around, but they tend to challenge other people, push them in order to
expand their boundaries, either for sake of the
relationship or just in general. And the people they tend
to push are the people that they pair up with, which are the people in the estrogen category,
what she called high estrogen. Again, they didn't measure estrogen, but the people in the estrogen
category were the ones that described themselves
and their choices in life and their preferences as being nurturing. They actually seem to
like it when someone else is making the major
decisions, not every decision. They certainly like to
be heard, of course, in terms of their preferences. But that those two types, what
she called the testosterone and the estrogen type tend to pair up. So why are these categorizations and these averages interesting to me, at least interesting
enough to convey to you? The reason they're interesting to me is, again, not because of their names, these molecules were not
measured in these individuals, but that they once again
bring us to the themes that we addressed before, which are the autonomic nervous
system and whether or not it tends to be shifted more
towards alertness in action or more towards a stable
equilibrium or more towards calm, and whether or not individuals
are selecting for people who have autonomic nervous
systems that are more or less like theirs before they even meet, right? So again, going back
to this seesaw analogy, it's almost like people
who have the flat seesaw, alert but calm, but not extremely alert, not extremely overly calm in
situations but in the middle, seem to be seeking out
people that are also at that autonomic equilibrium. People in the, what she
called the dopamine category, which are really can just be described as high sensation
seeking, novelty seeking, they seem to want to
pair with one another. So there's a selection for similar, in two of the groups, autonomic tone. I find that very interesting
because in that decision or that preference for
similar autonomic tone, it essentially eliminates
a lot of the requirement for figuring out how to match one's autonomic nervous system to another. They simply find someone with
a similar tendency, okay? Whereas in the other two
groups that she called testosterone and estrogen,
the director type and the nurturing somewhat follower type, there's an establishment of balance, but not in between two who
individuals as a match, but rather on the whole
in the relationship. One person is driving the novelty seeking in the course of decisions and actions, and the other person is
essentially agreeing to those. Now, assuming that those decisions
are good for both people. And I emphasize good for both people, because one of the themes
that Dr. Fisher underscores, and I'd like to underscore here as well, is that it need not be the
case that people pair up exactly according to these categorizations that I've described,
dopamine with dopamine, serotonin with serotonin,
testosterone with estrogen, and so on. What is important is that
there be a recognition and a respect for the other types, or a recognition and a
respect for the fact that both are of the same type. You could actually imagine,
for instance, that two people of this high sensation
seeking, novelty seeking could have a terrifically
exciting relationship, but that it actually
might be a relationship in which the financial
stability isn't quite there, or in which the basic
stability isn't there. You could imagine, for
instance, a situation in which a relationship between two people of what she called the
high serotonin preference would have a relationship
that was actually dull, in which both of them found
themselves bored at some point, or in which there wasn't
enough of the dynamic tension that sometimes is required
in order to keep this cycle of desire, love, and attachment going. Something that we will
talk about in a moment. So the point here is not that
one should necessarily pair up according to these
arrangements that I described. The point is that on average,
that's what tends to happen. And that through a recognition
that these categorizations exist similar to the
recognition that the type A, B, C, and D infant and
toddler type attachments exist, that we can gain better
self-awareness of who we are and how we tend to show up
in romantic attachments, and thereby navigate
healthier mate seeking, healthier breakups, if
the case dictates it, and in some cases healthy
long-term relationships by understanding that the other
person can either be similar or complimentary to us. One is neither better than the other. It's simply the case that
in all romantic attachments, from the initial inception
of the romantic attachment, desire, love, and attachment, there is an autonomic coordination. And of course there's
coordination of all sorts of other things like food,
sex, and sleep, and finances, and where people are going to
live, and many other features, but that at the core of
all that is a seeking of either autonomic likeness
or autonomic differences. And I think that recognition
can be extremely valuable in thinking about tools to enter
and maintain relationships. If one thinks about their
autonomic nervous system, not simply as something that
is driven by external people and events, but that we can
actually gain some control over through techniques of the sort
that I talked about earlier and on previous podcasts, but also generally, if
we are able to adjust our autonomic nervous system
in order to at least appreciate or get some empathy into what
someone else is experiencing, then we gain actual cognitive empathy. And this episode isn't
about empathy per se, but the theme keeps
coming up again and again. And I think it's worth
mentioning that when you talk to psychologists, whether
or not they're psychoanalyst or from another source of training, what you find is that they
don't talk about empathy as a general term, they will
talk about emotional empathy, they'll talk about cognitive empathy. And what I'm talking
about here today is that yet a third category that
is very strongly determinant of relationship dynamics,
and that's autonomic empathy. I'm a biologist, I'm not a psychologist. So I love mechanism. And fortunately there are
studies that have been done recently using modern techniques to look at neural mechanisms
of romantic attachment. I mentioned earlier some of
the brain imaging studies that have been done on child
and mother literally imaging the activity of neurons in
the brain as child is nursing, or as a mother is soothing baby, and as you learned earlier,
baby is soothing mother as well. Those are remarkable studies. You may have seen some
of these pictures online. You can see the silhouette
of the infant and mother, and their brains and even
some of the brain activation patterns, really, really
beautiful studies. Similar studies have been
done in romantic couples with those couples, either
touching one another, touching and kissing,
or in clever, I think, control experiments of the
person just touching a pillow, [laughs] or something, or kissing a pillow in order to try and create
the most reasonable control for what are actually pretty complicated interpersonal dynamics to do in a brain imaging scanner. But some of the other studies
that have been done recently involved so called EEG. So these are electrical recordings that are done noninvasively, putting a bunch of electrodes
on the outside of the scalp. EEG is useful in that you
can do it noninvasively, you can do it while people
are moving and doing things, kissing, touching, et cetera. It doesn't allow one to image
or to evaluate neural activity very deeply in the brain. So you can miss out on a lot of things. It's like looking at the
wave structure on the ocean without actually looking
into the depths of the ocean. So you can miss certain things, but if you see things generally
you trust they're there, but you can't see what you don't see. Nonetheless, there's some studies that I'll just point you
to and that form the segue for what I'm going to discuss in a moment, which is a study published in
Scientific Reports in 2021, entitled "Investigating Real Life Emotions in Romantic Couples: a Mobile EEG Study." So this is, as the title
suggests, having people wear these EEG caps of electrodes,
get engage in very passionate, emotional kisses, emotional
speech toward one another standing at different distances. So a lot of cool stuff that
you can do that you really couldn't do in a brain scanner,
because in a brain scanner, people have to be there
usually in a bite bar, they're actually jaw flicked like this. I've been in one of these things. There's not a lot of
moving around to be heard, at least not using the current technology. In any case, what they found was there is a shift in brain
waves, brain states, things like alpha waves or
just a particular frequency of brain waves in the
neocortex, the outer shell of the brain just beneath the skull. And in people that are kissing
or in people that are engaged in romantic speech, or I didn't
actually hear what they said to one another, but what
the couple seems exciting, romantic and arousing to
them, they see more alpha wave activity compared to
the control conditions. And there was some what
we call lateralization, where the left hemisphere was
more active than the right and so forth. And these studies are
important because we know that the autonomic nervous
systems of individuals tend to start to collaborate
and actually synchronize at the level of heartbeats,
at the level of breathing during romantic interactions
of different kinds. But these studies are some of the first of their kind to start looking at neural synchronization
between individuals. Now, the simple version of looking at this and the way I would've
thought this would all go was, okay, two people start
kissing, they start talking about what they find particularly romantic and arousing for them. And their brain waves will
just match to one another. And that's really the basis
of romantic attachment and romantic engagement
in that sort of thing. But it turns out that
the opposite is true. So a really nice study published
in a really fine journal, Cerebral Cortex is a
journal that I've known about for many years, they
published strong anatomy, physiology and neuroimaging. There's a study that was
published, first author, Kajimura, and this paper really points... Again, this is 2021. And the title of this paper is, "Brain Knows Who Is on
the Same Wavelength: Resting-State Connectivity
Can Predict Compatibility of a Female-Male Relationship." Now what this study did
was a little bit different. They looked at the resting or default mode activity of the brain. So rather than evoked
activity, as it's called, where people are kissing or
are engaged in some activity, this was a neuroimaging
study, not EEG, but fMRI, functional magnetic resonance imaging, which is similar to EEG in principle, but allows you to look
deep into the brain. And it has a very good
resolution in time and space. So fast events can be monitored
and the precise location of those events can be monitored
somewhat better than EEG. And there are exceptions to this. So for you EEGers out there. EEG don't come after me with electrodes. Just understand that fMRI
gives you a fuller picture of what's going on. And what Kajimura et al
found was that contrary to what your reflexive
prediction might be, people tend to select people
that have resting brain states that different than theirs, or sometimes they found
that are actually opposite to their own resting brain state. And you might say, "Well,
that doesn't make any sense. I thought this is all about
autonomic coordination." But actually if we go back to
Helen Fisher's categorizations of the dopamine types, the
sensation seeking types, that is serotonin, the
stable rule following types, testosterone and estrogen types, remember that the two
categories that she called testosterone and estrogen type, the director and the
follower, the nurturer, I guess it would be the more accurate way, the director and the nurturer, those tend to pair up across categories, not within category. And so I think what's
really needed for this field which to my knowledge hasn't happened yet, is to really start to
map the neuroanatomical and neurophysiological
findings of, in this case, that resting brain state is
in one form in one individual, and they tend to seek out
people whose resting brain state is different than theirs, not similar. That needs to be mapped
onto the more subjective psychological categorizations
that Helen Fisher and indeed the Gottman's
and others have created, that sort of the state of the field now. And I mentioned this not to confuse you, but to the contrary, to
illustrate that it's not just about finding someone just like you, and it's not just about finding someone who's opposite to you. This is actually the reason
that I decided to become a biologist at some point
in my life, which is that we can find verbal sayings,
and stories, and examples to support just about anything. This is not a knock on
the field of psychology, as you can probably tell
from today's episode. I have great respect for in reverence for the field of psychology,
especially its collaboration with neuroscience and vice versa. But in the popular culture, we can find examples and
sayings that support essentially anything as it relates to a relationship. For instance, I've heard
and you've probably heard, absence makes the heart grow fonder. And indeed I've experienced
that and I believe it's true. But I also have experienced
and I believe to be true that out of sight out of mind also exists and that there will be a
biological mechanism for that. The point here is that
matching of same to same or same to different can
both be effective in creating the desire, love, attachment process. It's a matter of, who is looking for same, and who is looking for different? And there, I think Dr. Fisher and the work of these neurophysiologist
and brain imagers really does point in a direction whereby there is not one form of attachment that is going to be
wholly above [indistinct] will predict good outcomes. There is not going to be a case
in which opposites attract, and that's always the best rule to follow. Sometimes it will, sometimes it won't. There is also not the
case that people tend to pair up with similar. Sometimes it will be the
case, sometimes it won't. Now there are certain statistics that support that statement. For instance, people, on average, people pair up with individuals
of similar educational background, income, and attractiveness. That is true on average, but
it's not always the case. And again, a knowledge of and
a respect for the different categorizations of attachment,
the different categorizations of mate seeking described
by Fisher and others, and the recognition that
matching of autonomic nervous systems but also mismatching
of resting state brain networks are all at play in driving
what we are calling desire, love and attachment. So in keeping with the
exploration of the fact that there's a saying, or a book,
or a song, or an example of pretty much any relationship dynamic, I want to now talk about an
article that came out a little over 10 years ago that talked
about the universality of love and the ability to fall in love. So this would be very much in line with the George Bernard Shaw
quote that I mentioned earlier that "Love is really overestimating the differences between individuals." And again, I should say
that is not something that I personally believe, although maybe I'm just diluting myself. I like to think that the
people that we fall in love with are really special for us, that they could not easily be
replaced with anybody else. That's simply my stance. I'm not basing that on any hardcore neurobiological mechanism. But nonetheless, an article was published in The New York Times in 2015 that related to some psychological
studies that were done, as well as some clinical
work, as well as some, what I would call pop
psychology or things that fall outside the domains of academic science. And the whole basis of this article was 36 questions that lead to love. And it involved a listing
out indeed of 36 questions, divided into set one, set two,
and set three that progressed from somewhat ordinary
questions about life experience and self-report to more, let's call them deep questions
about people's values and things that are
emotionally close to them. And I'll just give an
example of a few of these. You can find this easily
online by just putting into your search engine, 36
questions that lead to love. Some of the questions in set
number one, where for instance, what would constitute
a perfect day for you? For what in your life do
you feel most grateful? Kind of standard questionnaire stuff. In set two, what is your
most treasured memory? What is your most terrible memory? So these, as you can tell, are
drilling a little bit deeper into one's personal experience
and emotional system. And then set three, questions
25 through 36 are things, what is a very embarrassing
moment in your life? When did you last cry in
front of another person and by yourself? What is something that's too
serious to be joked about? So it's going deeper into
one's emotional system. And even questions like, of
all the people in your family, whose death would you find
most disturbing and why? So pretty, pretty heavy
stuff there at the end. Now, the reason this article
got so much traction, and the reason I'm bringing
it up today is that there was a statement that
was made in and around this article that if two
people went on a date or simply sat down and asked
each other these questions, and each answered these questions
and the other was paying attention carefully and at some
level emotionally responding or not out responding, but
certainly paying attention to the answers of the other person, that by the end of that
exchange, where one person asks 36 questions and the other
person answers all 36, and then the other person asks
all 36 and the other person answers all 36, that they
would fall in love, right? Which seems like a ridiculous thing. And yet it is the case that people who go through this exercise report
feeling as if they know the other person quite well
and feeling certain levels of attachment or even love and
desire for the other person that they were, would not
have predicted, excuse me, would not have predicted had they not gone through that process. So what's going on in
this exchange of questions and answers of a
progressively more emotional and deep level? Well, what I predict is
going on is that inside of that exchange, people are
creating a delusional story about the nature of the
exchange being a reflection of some deeper attachment. And so even though people
are just exchanging words, they're not physically touching,
they are not, at least not at the point where they're
running these kinds of questionnaire studies. They may touch afterwards for all I know, and probably did in some cases, but they're not exchanging life experience in an immediate way. They're not actually
going off into the world and doing things together yet. They are simply exchanging narrative. But we know based on recent
studies and I've covered this before on this podcast,
but I'll mention again, there was a study
published in Cell Reports, a Cell Press journal, excellent journal showing that when individuals
listen to the same narrative, their heart rates tend to synchronize or at least follow a very similar pattern, even if they're not in the same room listening to a given narrative. Whereas in this case, people
are facing one another listening to the narratives of each other. Certainly they are having
autonomic responses. And it stands to reason that
their autonomic nervous systems are synchronizing much
in the same way that the Cell Report study found
that people will synchronize their autonomic nervous
systems to a shared, heard story from another. In other words, whether
or not we hear a story, watch a movie, listen to a song, or exchange our own individual stories, our autonomic nervous
systems have the potential to map onto one another. So I'm not all that
surprised that people find that they fall in love, in quotes, after answering these
questions to one another, because essentially
the way these questions are laid out is they
establish a narrative. They establish a very personal narrative and the other person is
listening very closely. And we don't have physiological
or brain imaging studies to support what I'm about to say, but the reasonable interpretation is that that's causing some
autonomic synchronization. So if you want to try this on
a date or even it's actually been hypothesized that
this could be useful for existing couples, even if
they already know the answers to some of these questions. And that doesn't surprise me either. I think the autonomic
coordination is present during mating behavior, it's present during shared
experience of the outside world, movies, concerts, watching one's children with somebody else, et cetera. And it's established by
sharing one's own narrative of their own personal experience. So I don't want to seem
overly reductionist. I'll never propose that all
of our sensation, perception, action and experience in life
boils down to us just being bags of chemicals and the
action of those chemicals, or any aspect of our nervous system. And yet in looking across
the psychological literature of development of attachment,
in the psychological literature of adult and
romantic attachment, and what makes and
breaks those attachments, it's very clear to me. And I think courses through
the literature multiple levels, that autonomic coordination
is absolutely key for the establishment of
desire, love and attachment. In fact, I talked earlier
about how our actual conception is born out of autonomic coordination of one sort or another. So again, it doesn't necessarily
mean that autonomic nervous systems always be synchronized
in the case of the two categorizations that Fisher proposed of the director/testosterone type and the nurturing follower/estrogen type. It was actually the coordination
but in opposite directions of individuals that fall
into each of those categories that led to more stable attachments or the seeking out of those
attachments, I should say. But nonetheless, it's, at
least to my mind, very clear that autonomic coordination
is a hallmark feature of desire, a hallmark
feature of what we call love, and a hallmark feature of
what we call attachment. And that the breaking of
attachments were the failures of desire, the failures of love, and the failures of attachment over time in line with the work
of Gottman and others. And in even just simply what's
required for mating behavior is also reflected in the
autonomic nervous system. But in that case, a failure to coordinate the autonomic nervous systems
in some sort of concerted way. Any discussion about
desire, love, and attachment would be incomplete if we didn't talk about the
dreaded infidelity and cheating. Much has been made of
infidelity and cheating and whether or not people
who are higher on dopamine and sensation seeking tend
to cheat more or less. Frankly, I don't think there's
any solid evidence for that. I think there are a lot of
examples that we can draw from in our own lives and
in the lives of others that would generally support
one or the other model, but I'm not aware of any
decent physiological studies or psychological studies
that really point to that. For instance, I would never
say that the serotonergic phenotype as described by
Fisher is less prone to cheat, or that the people who
have an insecure attachment are more likely to cheat,
et cetera, for instance. I don't think those
correlations have been drawn in any kind of meaningful way yet. So I would be cautious
about assigning them without that evidence. However, there are some
interesting studies involving, again, neuroimaging and some
subjective measures in humans, meaning asking them questions that they're good ways to
tease out lies from truths in these sorts of studies and
whether or not people tend to find their partner or
others more or less attractive depending on how people
feel about themselves. And I think this is a
very interesting aspect to desire, love, and attachment
for the following reason. You hear a lot out out there that in order to form a really strong relationship, you have to have a good
relationship with yourself, or you have to love yourself. Or you often hear for instance
that it's exactly when you're not looking for a relationship
that you're going to find one. You hear this stuff, right? But none of that is really
grounded in any studies. Again, that's like out
of sight out of mind, or absence makes the heart grow fonder. There are many life examples
to support those statements. And there are many life examples to support statements to the opposite. There's a particular study that I found. This was published in
Frontiers in Psychology, but it's a experimental study
that involves neuroimaging. The title of this study is
"Manipulation of Self-Expansion Alters Responses to Attractive
Alternative Partners." And I love the design of this study. What they did in this
study is they took couples and they evaluated members
of that relationship for what's called self-expansion. Now self-expansion is
a metric that involves one's perception of self as seen through the
relationship to the other. And this is something
that was developed by, the authors are Aron and Aron. So they have the same last name. So I'm assuming this was
either a sibling team or a somehow related team
or a romantic couple team. A-R-O-N and A-R-O-N,
Aron and Aron, in 1986, proposed this self-expansion
model of close relationships. And they proposed "That
people are motivated to enter relationships..." I'm reading here. "In order to enhance the self
and increase self-efficacy." In other words, that one of
the reasons why many people enter relationships is
that it makes us feel good about ourselves and more capable. And I would see that as a
healthy interdependence, not necessarily codependence. This is especially strong at the beginning of a relationship, it turns out, when people are forming pair bonds, and it's the case that pleasure,
arousal and excitement, again, all hallmark features of autonomic nervous system function, pleasure, arousal and excitement, give rise to self-expansion,
meaning to self-efficacy. So what this self-expansion
model is really about is how great other people that we
are close to and romantically attached to can potentially make us feel, in terms of what they say,
in terms of what they do, in terms of the way in which
we believe they feel about us. So it doesn't necessarily
have to involve explicit statements of them telling
us how great we are, or them doing great gestures for us, but how we actually
feel they feel about us. Turns out to be a very
strong parameter in terms of how we feel about ourselves
and the relationship overall. Now, some of you out there
are probably thinking, "Oh yeah, isn't there this thing of the love languages?" Right? I don't have any neuroscience
to support, I think, the love languages, I'm not
super familiar with this, and I didn't list it out,
but that some people are... Their autonomic nervous
system, if you will, tends to be very responsive
to gifts, or to quality time, or to physical touch, or acts of kindness. I think I've got a few of these right. I probably have a few wrong. Anyway, they're easy to find online. And people do tend to have
a bias toward two or three of these things that are especially meaningful for them. And when I hear meaningful,
I hear they tend to push the autonomic nervous system
and neurochemical systems of the brain and body in a
direction that makes us feel good as opposed to lousy or neutral. In any event, this study
looked at whether or not people have high levels of self-expansion through the actions or statements of their significant other,
and how that influences their perception of people
outside the relationship. Meaning how attractive
they perceive people outside the relationship to be, turns out to be strongly influenced by, A, whether or not their
self-expansion is very strongly driven by the other person
that they are involved with, that they're in the
romantic relationship with, and whether or not that's
being expressed to them. So here's how the study went. First of all, they rated
or categorized individuals on the basis of the self-expansion metric. Some people have more of
a potential to experience self-expansion through others, right? Some of us feel great about
ourselves and we're topped off, the others don't feel so
great about themselves, but they can feel much
better in response to praise, in particular praise or
self-expansion type behaviors or statements from people
that we really care about. And still other people
are a mixture of the two. They moderate levels of both. So they rated them on this scale. And then they had people experience self-expansion narratives. They heard their significant
others say really terrific things about them and about the
relationship, in particular, that the relationship that
they have was exciting, novel and challenging. So that was one form of self-expansion. And they went into some detail
as to why that was the case in their particular relationship. Or they heard a narrative
from their significant other about strong feelings
of love between the two that had been experienced
previously in the relationship. So in the one case, it
directed more towards them. And in the other case, it's more about the relationship itself. And then they did brain
imaging of one person in the relationship while
that person assessed the attractiveness of people
outside the relationship. And what they found was
that people who were primed for this self-expansion had
lower activation of brain areas associated with assessing
others' attractiveness than did the people who experienced
a lot of self-expansion. Now the takeaway from that,
at least the way I read the study is if you're with
somebody who really benefits from or experiences a
lot of self-expansion, unless you really want
them to pay attention to the attractiveness of other people, it stands to reason
that they would benefit from more self-expansion type
gestures or statements, okay? Not so much centered on the relationship. We have such a great relationship. There's so much love,
it's so great, that too, but in the context of this
study and these findings, that the person is really
terrific, that the relationship that they've created
together is really exciting, novel, and challenging, that
there's a narrative around the relationship that
really has a lot to do with the dynamics between the
individuals, in particular, that the person who really
likes self-expansion is vital to that dynamic, okay? So it's not looking
down at the relationship as a set of equals. There is this bias
written into this of that this person is really
essential for the relationship. I'm not saying this is
something that anyone has to do. I'm not not saying this is right or wrong. This is just what the data say. But what's remarkable
is that in the absence of those statements, people who have, or that rate high on this
scale of self-expansion rate attractive alternative
partners as more attractive. Now, that's interesting to
me, because it may means that their actual perception
of others is changing. It's not that their opportunity to see others is changing, right? This is not a matter of
them somehow getting access or no access to attractive
alternative partners. Again, attractive alternative partners, literally the language in
the title of this paper, they're still seeing all
these attractive people. It's just that if they're
feeling filled up, in air quotes, psychologically filled
up, emotionally filled up, autonomically filled,
enhanced in the language that we're using today by
the self-expansion narrative, well then the same set of
attractive faces appear less attractive to a given individual. Now, whether or not this
predicts cheating or loyalty, [laughs] I certainly can't say. That would be very hard
to assess in neuroimaging. And there, of course,
people rarely if ever report accurately their cheating behavior. There's some studies in which
confidentiality is assured to the point where people
seem to be more trusting and willing to reveal cheating behavior. But if you look at the
statistics on cheating behavior, it's very hard to track
because people lie all the time about their cheating in
and outside of the context of psychological and neuroimaging studies. But I find this study, again, the title, "Manipulation of
Self-expansion Alters Responses to Attractive Alternative Partners" to be absolutely fascinating,
because again, it points to the fact that the
interactions with our significant others shapes our autonomic
arousal, shapes our perception of self and thereby shapes our
perception of other potential partners in the outside world, or shuts us down to the
potential of other people in the outside world. So when I hear statements such as, it's important that you love yourself in order to really fall in
love with somebody else, or it is when one is not
looking for a relationship that they're most likely to fall in love and form a stable relationship, I can filter that through
these findings to say that it's really the person who
needs a lot of self-expansion, stimulating statements or
actions coming from other people that is most prone to seeing
other potential partners out in the world as attractive. And in this sense, we can return to the
autonomic nervous system as a glass that it can be filled up through various contexts. It can be filled up through
our own ability to regulate it. It can be filled up through
other people's ability to enhance our sense of wellbeing. And in some sense, this points
to an idea where it is true that the better that we
can feel about ourselves in the absence of any
self-expansion type input from somebody else really does place us on more stable grounds,
such that when we do receive that praise, or we do receive
those acts of kindness, or service, or physical
touch or whatever they are, that we are able to further
enhance the way that we feel, but that we don't necessarily
tether all of our feelings of self-worth or self-expansion
to that one individual. So you might think that if
person A can only receive the self-expansion from the
statements, from the action of the they're involved with, person B, that that will form a very stable bond, but what this study
points to is the fact that that's a very unstable bond. That person A is actually very susceptible to the attractiveness of others, because they're so desperately
attached to this notion of self-expansion, even
if they don't realize it. And so this really does
point to the idea that, well, it is important to link
our autonomic nervous systems to establish desire, love, and attachment that we want to have a stable
internal representation of ourselves, a stable
autonomic nervous system to some degree in other so
that we can be in stable romantic partnership
with another individual, if that what we're really trying to do. So until now, I've been
weaving together studies from the field of experimental psychology and the fields of neuroscience
in particular neuroimaging. But if you recall back to the
very beginning of the episode, when I was discussing how
odors, and how hormones, and how even birth control
can shape people's ratings of attractiveness of others, you'll realize that there's
a deeper layer to all this, which is that our biology that
resides below our conscious awareness, things like our hormones, things like pheromones
even are shaping the way that we choose, interpret
and act with other potential romantic partners or the romantic partners that we already have. Now, this cannot be
over-emphasized, right? No matter how much we would like to create a top-down description,
meaning from the cortex and our understanding of things onto what we find attractive,
who we find attractive, what we enjoy, what we
don't enjoy in the pursuit in romantic interactions with others, there always seems to be,
and indeed, there always is a deeper layer in which
our subconscious processing drives us to find a particular person to be particularly attractive, or in which we have
chemistry with somebody, or in which we lack
chemistry with somebody. And I would say that one of
the more exciting, fascinating, and indeed mysterious aspects
of desire, love and attachment are those subconscious processes, those things that we
call chemistry, right? I mean, people will report,
for instance, that somebody's smell is just absolutely
positively intoxicating for them, or that somebody's smell is
absolutely repulsive to them and they don't know why. That the taste of someone's
breath, and I don't mean that in any kind of poetic sense,
I literally mean the taste of somebody's breath in some cases can be very exciting to somebody. And believe it or not, we can
taste each other's breath. I talked about this in the
chemical sensing episode some months back, but we
actually have receptors for taste and smell that engage
in coordinated action, such that we can't really
separate taste and smell at some level. And this is especially true
when it comes to the formation of romantic relationships
and what we call chemistry. Now is chemistry absolutely required for forming stable attachments
for love and for desire? No, of course, they're not. But in general, these
are primitive mechanisms that exist in all animals, they exist in special forms in humans, but that they drive us
toward behaviors that will, as the theory goes, lead
to love and attachment. Not always, as Dr. Fisher pointed
out that sex and sex drive is one way to explore
potential love relationships, and to explore potential attachments, which, of course, are major investments that extend well beyond one
night, or a week, or a vacation, or even a year. When we talk about stable attachments, in general, that means
long-term attachments in humans. Now, there is a biology to
all of that chemistry stuff. And the studies of oral
contraception and men finding women more attractive at certain
phases of their menstrual cycle, and women finding men more
attractive at certain phases of the women's menstrual cycle
point to the incredible power of those deeper biological mechanisms. In the "Huberman Lab Podcast," I discuss both science
and science-based tools. And so I'd be remiss if
I didn't actually cover some of the tools that relate to those deeper biological mechanisms. Now, the hormones,
testosterone and estrogen are almost always the
first biological chemicals and hormones that are mentioned,
and described, and explored when thinking about desire,
and love and attachment, too, for that matter since love and
attachment stem from desire. I did an entire episode about
the biology of testosterone and estrogen and ways to optimize
testosterone and estrogen. You can easily find that
episode at hubermanlab.com. It's timestamped, there
you can find all sorts of information about how
certain behaviors or absence of behaviors drive up or down
testosterone and estrogen. I also dispel some myths
about sexual behavior and things like masturbation and how they relate to
testosterone and estrogen, as well as some myths about
how those hormones change across the lifespan. I also talk about the role of exercise, I talk about supplementation,
and I also talk a little bit about hormone replacement therapy, although that will be the
topic for a future episode. So if you're interested in
the biology of testosterone and estrogen, two hormones
that absolutely influence things like libido and desire,
please check out that episode as well as what I'm going to
talk about in just a moment here. The simple stereotyped
version of the hormones, testosterone and estrogen
are that testosterone drives libido or increases it aka sex drive, and that estrogen somehow
blunts it or is not involved in libido and sex drive. And that is simply not the case. As I describe in that
testosterone and estrogen optimization episode and
as I'll tell you now, yes, testosterone and
some of its other forms like dihydrotestosterone are
strongly related to libido and sex drive and the
pursuit and ability to mate. However, the hormone estrogen
is also strongly associated with libido and mating behavior. So much so that for people
that either chemically or for some other reason
have very low estrogen, libido can severely suffer. So it's a coordinated dance
of estrogen and testosterone in both males and females that
leads to libido or sex drive. So I absolutely want to make
clear that it's not a simple relationship between
testosterone and sex drive, or estrogen and sex drive. Both are required at appropriate ratios. Now, with that said, there are
things that can shift libido in both men and women in
the direction of more desire or more desire to mate,
either to seek mates or to mate with existing partners. And there's a quite solid literature around a few of those substances. Now, a common misconception
is that because dopamine is involved in motivation and
drive that simply increasing dopamine through any number of
different mechanisms or tools will increase libido and sex drive. And that's simply not the case either. It is true that some level
of dopamine or increase in dopamine is required
for increases in libido. However, because of
dopamine's relationship to the autonomic nervous system, and because the autonomic nervous system is so intimately
involved, no pun intended, in sexual activity in seeking
an actual mating behavior, as I described earlier,
it's actually the case that if people drive their
dopamine system too high, they will be in states of
arousal that are high enough such that they seek and
want sexual activity, but they can't actually
engage the parasympathetic arm of the autonomic nervous system sufficient to become physically aroused. There's a whole description
of this that awaits us in a future episode. But I'll summarize now
by saying for people that are taking substances just
simply to increase dopamine in order to increase libido, that can be a potentially
hazardous route to follow. Because depending on whether
or not that dopamine level is high enough that it puts
them into a mode of seeking mates or mating, but they
can't adjust their autonomic nervous system during
actual mating behavior, what essentially is I'm
saying is it can place people into a chronic pursuit but in
inability to perform sexually. And this is true for men and women. Okay, so I would just caution
people against just thinking, "Oh, a lack of libido is
simply a lack of dopamine." That is not the case. It could be from lower levels of dopamine, but it could also be for other reasons. And so these systems,
these signaling systems and these neurochemicals
are very intricate. And just simply ramping up
dopamine has actually been found, for instance, in amphetamine
and cocaine users, there's a phenomenon in which
they become hyper aroused, but can't perform sexually. This is also true for people
who take elevated levels of other recreational drugs
or who take antidepressants that increase the dopamine
system too much, right? Dosage has to be worked
out with your physician, with your psychiatrist,
such that mood is enhanced and the various aspects
of a healthy wellbeing, mind and body are enhanced,
but not so much so that that what we call the arousal
arc is locked with the seesaw in the sympathetic drive position such that sexual arousal
can't occur, okay? So this is an important point to make, because I think that a lot of people are under the impression that if they just drive up
testosterone, increase dopamine, and generally get
themselves into high states of autonomic arousal that that's
going to increase the libido. But that's simply not
the way the system works. It's that seesaw and that
seesawing back and forth that is the arc of arousal
that we talked about earlier. Now, there are substances, legal
over-the-counter substances that fall under the
categorization of supplements that do indeed increase
libido and arousal. And so I'm going to talk about
some of those in the context of peer-reviewed literature now. I want to be clear, however, that these are by no means required. Many people have healthy
libidos or have libidos that are healthy for their life
and what they need and want. And as always in any discussion
about supplementation, you absolutely have to
check with your physician. I don't just say that to protect us. I say that to protect you. Your health and wellbeing is
dependent on you doing certain things and not doing others,
and everybody is different. Nonetheless, there are studies that point to specific substances that
are sold over the counter that at least in the
United States are legal and that have been shown to
be statistically significant in increasing measures of libido. There are many such substances,
but three that in particular have good peer-reviewed
research to support them are Maca, M-A-C-A, which
is actually a root. Tongkat Ali, also
sometimes called longjack, I didn't name them, forgive
me, and Tribulus, or Tribulus, it's sometimes called. I'm going to talk about
each of these in sequence. But on the whole, the studies
on Maca are quite convincing that consumption of two to
three grams per day of Maca, which generally is sold
as a powder or a capsule, typically consumed early in the day, because it can be somewhat of a stimulant, meaning it can increase alertness
and you wouldn't want it to interfere with sleep by
taking it too late in the day. But in studies that include
both men and women of durations anywhere from eight to 12 weeks of athletes and non-athletes, and different variations of Maca, turns out there's black
Maca, red Maca, yellow Maca. There are a bunch of
different forms of Maca. But that they can increase
subjective reports of sexual desire, independent
of hormone systems. Meaning, it does not seem at
least based on the existing literature that Maca
increases testosterone or changes estrogen, at
least not on the time scales that these studies were done, or with the measures that were
performed in these studies. But that Maca, again,
consumed in doses of anywhere from two to three grams per day, has been shown to
significantly increase libido. And in fact, those dosages of
Maca have been shown to offset so-called SSRI induced sexual dysfunction. So there are various routes
to sexual dysfunction. The SSRIs are selective
serotonin reuptake inhibitors. They go by name brands
like Prozac and Zoloft, and there are many others now
on generic forms and so forth. Those don't always, I should point out, lead to sexual dysfunction. There's a dose dependence. Some people do quite well on
SSRIs and don't have any issues with sexual function. Other people suffer quite a
lot from sexual dysfunction while taking SSRIs, highly variable. You need to work with a physician,
a qualified psychiatrist. But nonetheless, everything
I've been saying about Maca thus far has also been
explored in the context of SSRI induced sexual dysfunction. The paper that I'm referring to here is "A Double‐Blind, Randomized,
Pilot Dose‐Finding Study of Maca Root..." It goes by the name L. meyenii. These always have fancy names. And the Latin names in biology
are always more complicated, but it's Maca root. "for the Management of
SSRI‐Induced Sexual Dysfunction." First author is Dording, D-O-R-D-I-N-G. This was a study done at Mass General, which is one of the satellite
locations around Harvard Med. It's associated with Harvard Med, that found significant
improvements in libido when people were taking a pretty low dose. It was actually in this
case, just 1.5 grams per day, up to a high dose, three
grams per day of Maca. And they were doing this in 20 remitted depressed outpatients. So these are people that had depression, their depression was
successfully treated with SSRIs, but they were suffering from
some of these SSRI related sexual effects and Maca seemed to offset some of those effects
significantly in this population. The other studies exploring
the lack of effect on serum testosterone in adult healthy
men was a 12-week study, again, consuming anywhere
from 1.5 to three milligrams, meaning one, excuse me, 1500 milligrams to 3000 milligrams or placebo. So again, this is 1.5 up to
three grams of Maca or placebo, and they rated sexual desire,
depression, and other measures such as testosterone in the blood. Again, no change in
testosterone or estrogen estradiol levels in men treated with Maca and those treated with placebo. But nonetheless, there was a
significant and positive effect on libido with this dosage of 1.5 to three grams per day of Maca. And there are several other
studies that also show this. Again, in people that taking
SSRIs and people that are not taking SSRIs, in chronically
over-trained athletes, this was also found to be the case. So seems like across the board, Maca is a fairly useful supplement for those that are seeking
to increase their libido. And there are fewer
studies involving women, but there are a few such studies
that also point to the same general positive effect on
libido in women taking Maca at equivalent doses to
those I just described. I think it's noteworthy
that Maca supplementation does not seem to adjust
testosterone or estrogen levels to any significant degree,
but it does change libido. I think that points to the
fact that there are multiple systems in the brain and
body that influence libido, not just testosterone and estrogen. And indeed we know that to be the case. Things like PEA, which is a
substance found in chocolate and is a substance that
some people supplement, is known, for instance,
to increase sexual desire, but also the perception
of sexual experiences as more stimulating for instance. So there are a lot of pathways
in the brain, in particular, in the hypothalamus, this
ancient area of our brain, that harbors neurons and
hormone secreting cells, including neurons that
can shape our perceptions of even just our tactile experience of others and their attractiveness. And indeed can shift levels
of desire, independent of changing levels of
circulating hormones. Another substance that has
been shown to increase libido across a range of human populations is so-called Tongkat Ali. I've talked a little bit about this before on the "Huberman Lab Podcast"
in reference to testosterone. And I've talked about it
extensively as a guest on other podcasts. Tongkat Ali goes by a
number of different names. One of them is exceedingly
difficult for me to pronounce. It's Eurycoma longifolia,
also called longjack. But Tongkat Ali is the typical name. This is an herb, there's
a Malaysian version and an Indonesian version. My understanding is that
the Indonesian variety of Tongkat Ali is the
one that is most potent for its effects on libido. Previously, I've talked about Tongkat Ali taken in 400 milligram per day capsules as a means to increase the amount of free, meaning unbound testosterone. So testosterone has a both
bound form and an unbound form. Very briefly, the bound
form is bound to albumin in the blood or to so-called
sex hormone binding globulin. When it's bound, it can't
be biologically active at many cells. It is important that some
of it be bound in order to get a time release
and proper distribution of testosterone through the body, but is the unbound free
testosterone that can really have its most potent effects. And there's some evidence
that Tongkat Ali can increase the amount of unbound
so-called free testosterone by lowering sex hormone binding globulin, although it is almost certain
that it has other routes of mechanism as well. Nonetheless, there are
some reports of Tongkat Ali increasing libido. One particular article,
last author, or I should say last name of first author,
excuse me, Ismail, I-S-M-A-I-L. This was published in
Evidence-Based Complementary and Alternative Medicine, it's from 2012. Reports a significant increase in libido and sexual function. There are other studies,
not a lot of them, not as many robust, controlled,
quality peer-reviewed studies as there are from Maca. Nonetheless, a number of people,
men and women that I know do take Tongkat Ali and it
seems to work well for them. The question always comes up around discussion of supplements. Do you need to cycle these things? The only way to determine that is really to do your blood work,
monitor liver enzymes, monitor hormone levels and so forth. So I simply can't say
whether or not you need to, or you don't need to cycle them. Typically Tongkat Ali
and Maca are not cycled in any regular kind of
way that I'm aware of. But again, you really need
to check with your doctor if you're going to initiate
taking any of these things. And you certainly should
do your best to monitor your blood work as well as
subjective measures in evaluating whether or not they're working for you, safe for you and so forth. The third and final substance/supplement that I want to touch on
as it relates to libido is called Tribulus Terrestris. So that's T-R-I-B-U-L-U-S,
terrestris, T-E-R-R-E-S-T-R-I-S. This is a commonly sold
over-the-counter supplement for increasing testosterone, for fitness purposes and so on. Whether or not it actually does that to a meaningful degree, isn't clear. But I'm aware of four
peer-reviewed studies that were focused on
both males and females ranging anywhere from 18 years old all the way up to 65 plus. They say 65 plus. I guess it could be 70, it could be 80. I don't know. But a fairly broad age range
where people took anywhere from 750 milligrams per day
divided into three equal doses. So 750 total per day divided
into three equal doses of Tribulus or placebo for 120 days. This particular study
was focused on females. And according to the female
sexual function index questionnaire, no significant difference between any of the groups,
however free and bio-available testosterone increased in the group taking Tribulus Terrestris, total testosterone did not reach statistical significance. So this is the inverse
of what we see with Maca, where there do seem to be
increases in testosterone, which would predict that there
would be increase in libido. In this case, this was
postmenopausal women, there was no increase in libido. There was an increase in testosterone. I mentioned it only because
there might be instances in which people want to
increase their testosterone. It does seem that Tribulus,
at least in that population is capable of doing that. Now there's a separate
study that was done, a double-blind study lasting
anywhere from one to six months that had a clear and
significant increase in libido. Now this was taking six grams. So that's 6,000 milligrams
of Tribulus root for 60 days. And it did seem to
increase various aspects of sexual function. And there was what appeared
to be a substantial 16.3% increase in testosterone,
but in this particular study because of the variability
across individuals that did not actually arrive
at statistical significance. Now, there were a number of
other studies that explored the role of Tribulus, in
particular, in females. And one of those studies was a study that was actually quite short,
it was two to four weeks. It involved 67 subjects. These were subjects that had
experienced a loss of libido and took Tribulus divided
into two equal doses, compared that to placebo. And they did see a significant
improvement in these measures of sexual desire and function on this female sexual function index. So there is some evidence
that Tribulus can be effective in increasing testosterone
in certain populations, in increasing sexual desire and function in certain populations
in particular in females. I think more studies are certainly needed. But these three substances/supplements, Maca, Tongkat Ali, in particular,
Indonesian Tongkat Ali, and Tribulus can indeed create significant increases in sexual desire. And in some cases by
adjusting the testosterone and estrogen system, in
some cases not by adjusting the testosterone and estrogen system. Again, pointing to the
complexity of neurochemicals and features that adjust
things like libido aka desire. So we covered a lot of
material today related to desire, love, and attachment. And yet I acknowledge
that it is not exhaustive of the vast landscape that
is the psychology and biology of desire, love and attachment. Nonetheless, I hope that
you found the information interesting and hopefully
actionable in some cases toward the relationships
of your past, of present and potentially for the
relationships of your future. If you're enjoying and or
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neuroscience-related tools on both Instagram and Twitter. Some of that material overlaps with material covered on the podcast. Some of it is unique material only covered on Instagram and Twitter. During today's episode and
on many previous episodes of the "Huberman Lab Podcast,"
we discussed supplements. While supplements aren't
necessary or appropriate for everybody, many people
derive tremendous benefit from them, for things like
enhancing sleep, enhancing focus, or as discussed today for
enhancing libido and desire. If you want to see the
supplements that I take, you can go to Thorne, that's
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amounts of those supplements. Thank you for joining me
for today's discussion about desire, love, and attachment. And last but certainly not least, thank you for your interest in science. [upbeat music]
