The Science of Love, Desire and Attachment

- 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.

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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.