Welcome to Huberman Lab Essentials,

where we revisit past episodes for the

most potent and actionable science-based

tools for mental health, physical

health, and performance.

I'm Andrew Huberman and I'm a professor

of neurobiology and opthalmology at

Stanford School of Medicine. Today we

are going to talk about the psychology

and the biology of desire, love, and

attachment. 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. 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's some toys in the room

and typically the mother and the

stranger will talk. Obviously the

stranger is part of the experiment. It's

not just some random person off the

street and the child is allowed to move

about the room. They can play with toys

or not. But then at some point the

mother leaves and then at some point

later designated by the experimentter

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. 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. The first style is the

so-called secure attachment style. The

secure attachment style is one in which

the child will engage with the stranger

with the experimentter while the parent

is present in the room but that when the

parent or other caregiver leaves the

child does get visibly upset. However,

when the caregiver meaning the mother or

father or other caregiver returns the

child visibly expresses happiness that

the caregiver has returned. 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. These children are also

very good at exploring novel

environments after the parent is gone

and while the parent is there. The

second category is a so-called anxious

avoidant or insecurely attached. They do

not exhibit distress on separation and

they generally tend to have um some

tendency to approach the the the

caregiver when they return but there

doesn't seem to be a general expression

of joy. The third category is the

so-called anxious ambivalent

slashresistant insecure category. 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. And the

third category of attachment style is

the so-called disorganized or

disoriented or D for the letter D uh

babies. It seems like these children

just don't really know how to react to a

separation and they just uh start to

manifest behaviors and emotional tones

that aren't observed in other

situations. 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. 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. 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, uh, it's so, uh, 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. Instead, there

are multiple brain areas that through

their coordinated action create a sort

of a song that we call desire or a song

that we call love or a song that we call

attachment. not a a literal song, 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. So the way to think about the

autonomic nervous system is it's kind of

a seessaw. 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 kind of sleepy, semicol um and

but still also alert. So think about it

like a seessaw and that seesaw has a 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

seessaw 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 seessaw. 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 for many decades

afterwards. Conversely, if the parent

and in this case again it was mothers

that that were explored in these studies

had turned this whole business of going

into the bomb shelters into somewhat of

a game. All 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. 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 um 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 a hallmark of of strong and

quality attachments. 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. So if the autonomic nervous

system is one key component of desire,

love and attachment, what are the other

two? 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 uh 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 etc.

It is a universal generic currency in

the brain for pursuing something. 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 and

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 seessaw is

driving your seesaw or your seessaw is

somehow driving their seessaw. That's a

form of empathic matching. And there are

indeed neural circuits for that. 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 su l a.

The insula is a really interesting brain

area that allows us to interoscept to

pay attention to what's going on inside

our body and to split some of our

attention to extercept. 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 body bodily sensations

of the other. Okay? 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

is the neural circuit associated with

self-d delusion. What do we mean by

positive delusion? Positive delusion is

belief that only this person can make me

feel this way. Now positive delusion is

critical. If you look at the stability

of relationships over time, 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 and 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 Gottmans. It's actually a husband

and wife team up at the University of

Washington in Seattle. And they've

identified what are called the four

horsemen of relationships. Those four

behaviors, what they call the four

horsemen of the apocalypse

uh for relationships are one criticism,

two defensiveness, three stonewalling,

and four contempt. With contempt being

um the most powerful predictor of uh

breaking up. Um criticism of course does

not mean that there's uh no place for

criticism in stable relationships. Of

course there is. It has to do with how

frequent and how intensely that

criticism is voiced. Defensiveness

of course is defensiveness uh we know as

the sort of lack of ability to hear

another or to adopt their stance. So

lack of empathy I think is is a 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 uh the

emotional response or the request of

another is completely cut off 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

uh such a powerful predictor of divorce

and breakups uh in the future. Contempt

of course uh by definition is the

feeling that a person or thing is

beneath consideration, worthlessness or

deserving scorn. The runs counter to all

of the neural circuits, all three of the

neural circuits that we talked about

before. It certainly is um 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 kind of 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

seessaw from their seessaw. They're very

excited about something. You're

unexcited by it. And therefore, it's not

um surprising that it is so strongly

predictive of breakups. And in the case

of married couples of divorce, 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.

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 uh what I would call um pop

psychology or things that fall outside

the the domains of academic science. And

the the whole basis of this article was

um 36 questions that lead to love. And

it involved a listing out indeed of 36

questions set divided into set one, set

two, and set three that progress from

somewhat ordinary questions about life

experience um and self-report to more,

let's call them deep questions about

people's uh values and and things that

are emotionally close to them. And I'll

just give an example of a few of these.

Some of the questions in set number one

were um 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, um what is your most

treasured memory? Uh was your most

terrible memory? So these are are as you

can tell are drilling a little bit

deeper into one's um personal experience

and and emotional system. And then set

three questions 25 uh through 36 um are

things um you know what is a a very

embarrassing moment in your life? Uh

when did you last cry in front of

another person uh and by yourself? what

is something that's too serious to be

joked about. So, it's going um deeper

into uh one's emotional system. 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 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 kind of 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 uh

levels of attachment or even love and

desire for the other person that they

would not have predicted uh 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? We know based

on recent studies, and I've covered this

before on this podcast, but I'll mention

again, 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. So, I'm not all that

surprised that people find that they

fall in love in quotes um 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. So, I don't

want to seem overly reductionist. You

know, I will 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 at multiple levels 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. You

hear a lot out there that you know in

order to form a really strong

relationship uh you have to have a good

relationship with yourself or you have

to love yourself or uh you often hear

for instance that you know 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. There's a particular study that

I found uh this was published in

frontiers in psychology but it's a

experimental study that involves um

neuroiming. 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. 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. 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 this

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 kind of topped off at 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 um behaviors or statements from

people that we really care about. And

still other people are a mixture of the

two, the kind of moderate levels of

both. So they rated them on this scale.

And then they had people experience

self-expansion

narratives. They heard their significant

other say really terrific things about

them and about the relationship in

particular that the relationship uh 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 a 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

sort of 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 sort of 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

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 means that their actual

perception of others is changing.

They're still seeing all these

attractive people. It's just that if

they're feeling filled up, uh, in air

quotes, uh, psychologically filled up,

emotionally filled up, autonomically

filled, uh, enhanced, uh, in in the

language that we're using today by the

self-expansion narrative, well, then the

same set of attractive faces appear less

attractive to a given individual. Now,

whether or not this predicts cheating or

loyalty, uh, I certainly can't say. That

would be very hard to assess in in

neuroiming.

I find this study again the title

manipulation of self-expansion alters

responses to attractive alternative

partners to be absolutely fascinating

because again it points to the fact that

the interactions with our significant

others shapes our autonomic arousal

shapes our perception of self and

thereby shapes our perception of other

potential partners in the outside world

or shuts us down to the potential of

other people in the outside world. And

so this really does point to the idea

that while it is important to link our

autonomic nervous systems to establish

desire, love, and attachment, that we

want to have a stable internal

representation of ourselves, a stable

autonomic nervous system to some degree

or another so that we can be in stable

romantic partnership with another

individual if that's what we're really

trying to do. In the Huberman Lab

podcast, I discuss both science and

science-based tools. And so, I'd be

remiss if I didn't actually cover some

of the tools that relate to those deeper

biological mechanisms.

Now, the hormones testosterone and

estrogen are almost always the first

biological chemicals and hormones that

are mentioned and described and explored

when thinking about desire and love and

attachment too for that matter. Since

love and attachment stem from desire,

the simple stereotyped version of the

hormones testosterone and estrogen are

that testosterone drives libido or

increases it, aka sex drive, and that

estrogen somehow blunts it or is not

involved in libido and sex drive. And

that is simply not the case. Yes,

testosterone and some of its other forms

like dihydrotestosterone

are strongly related to libido and sex

drive and the pursuit and ability to

mate. However, the hormone estrogen is

also strongly associated with libido and

mating behavior. So much so that for

people that either chemically or for

some other reason have very low

estrogen, libido can severely suffer.

So, it's a coordinated dance of estrogen

and testosterone in both males and

females that leads to libido or sex

drive. With that said, there are things

that can shift libido in both men and

women in the direction of more desire or

more desire to mate either to seek mates

or to mate with existing partners. Now,

a common misconception is that because

dopamine is involved in motivation and

drive that simply increasing dopamine

through any number of different

mechanisms or tools will increase libido

and sex drive. And that's simply not the

case either. It is true that some level

of dopamine or increase in dopamine is

required for increases in libido.

However, because of dopamine's

relationship to the autonomic nervous

system, and because the autonomic

nervous system is so intimately

involved, no pun intended, in sexual

activity, in seeking and actual mating

behavior, as I described earlier, it's

actually the case that if people drive

their dopamine system too high, they

will be in states of arousal

that are high enough such that they seek

and want sexual activity. but they can't

actually engage the parasympathetic arm

of the autonomic nervous system

sufficient to become physically aroused.

So this is a an important point to make

because I think that a lot of people are

under the impression that if they just

drive up testosterone, increase

dopamine, and generally get themselves

into high states of autonomic arousal

that that's going to increase their

libido. But that's simply not the way

the system works. It's that seessaw and

that seesawing back and forth that is

the arc of arousal that we talked about

earlier. Now, there are substances,

legal over-the-counter substances, uh

that fall under the categorization of

supplements that do indeed increase

libido and arousal. I want to be clear,

however, that these are by no means

required. Uh many people have healthy

libidos or have libidos that are healthy

for uh their life and and what they need

and and want. Um, and as always in any

discussion about supplementation, you

absolutely have to check with your

physician. I don't just say that to

protect us. I say that to protect you.

Your health and well-being is dependent

on you doing certain things and not

doing others. And everybody is

different. Nonetheless, there are

studies that point to specific

substances that are sold over the

counter that at least in the United

States are legal and that have been

shown to be statistically significant in

increasing measures of libido. There are

many such substances but three that in

particular have good peer-reviewed

research to support them are maca m a ca

which is actually a root tongat ali also

sometimes called longjack I didn't name

them forgive me and tribulus or tribulus

it's sometimes called I'm going to talk

about each of these in sequence but on

the whole

the studies on maca are quite convincing

that consumption of two to three grams

per day of maca which generally is sold

as a powder or a capsule

typically consumed early in the day

because it can be somewhat of a

stimulant meaning it can increase

alertness and you wouldn't want it to

interfere uh with sleep by taking it too

late in the day. But in studies that

include both men and women of durations

anywhere from 8 to 12 weeks of athletes

and non-athletes and different

variations of maca. Turns out there's

black maca, red maca, yellow maca. There

are a bunch of different forms of maca,

but that they can increase subjective

reports of sexual desire

independent of hormone systems. Meaning

it does not seem at least based on the

existing literature that maca increases

testosterone or changes estrogen at

least not on the time scales that these

studies were done or with the measures

that were uh performed in these studies.

Another substance that has been shown to

increase libido across a range of human

populations is so-called Tongat Ali.

This is an herb. There's a Malaysian

version and an Indonesian version. Um my

understanding is that the Indonesian

variety of Tonga Ali is the one that is

most potent for uh its effects on

libido.

Previously I've talked about Tonga Ali

taken in 400 mgram per day capsules as a

means to increase the amount of free

meaning unbound testosterone. So

testosterone has a both bound form and

an unbound form. Very briefly, the bound

form is bound to albumin in the blood or

to so-called sex hormone binding

globbulin. Uh when it's bound, it can't

be biologically active at many cells. Uh

it is important that some of it be bound

in order to get a sort of time release

and and proper distribution of

testosterone through the body, but is

the unbound free testosterone that can

really have its most potent effects. And

there's some evidence that Tonga Ali can

increase the amount of unbound so-called

free testosterone by lowering sex

hormone binding globbulin although it is

almost certain that it has other routes

of mechanism as well. Nonetheless, there

are some reports of Tonga Ali increasing

libido. The question always comes up

around discussion of supplements. Do you

need to cycle these things? The only way

to determine that is really to do your

blood work. Monitor liver enzymes. u

monitor hormone levels and so forth. So

I I simply can't say whether or not you

um need to or you don't need to cycle

them. Typically uh tonga ali and macaka

are not cycled in any regular kind of

way that I'm aware of. But um again you

really need to check with your doctor if

you're going to initiate taking any of

these things. Um and you certainly

should do your best to monitor your

blood work as well as subjective

measures and evaluating whether or not

they're working for you, safe for you,

and so forth. The third and final

substance supplement that I want to

touch on as it relates to libido is

called tribulus terrestus. So that's T R

I b u lus terrestus t

u this is a commonly sold

over-the-counter supplement for

increasing testosterone for you know

fitness purposes and and so on. Whether

or not it actually does that to a

meaningful degree uh isn't clear, but

I'm aware of four peer-reviewed studies

that were focused on both males and

females um ranging anywhere from uh 18

years old all the way up to 65 plus. a

fairly broad age range um where people

took anywhere from

uh 750 milligrams per day divided into

three equal doses. So 750 total per day

divided into three equal doses of

tribulus um or placebo for 120 days. Um

this particular study was focused on

females. Um and according to the female

sexual function index questionnaire um

no significant difference between any of

the groups. However, free and

bioavailable testosterone increased in

the group taking tribulus terrestus.

Total testosterone did not reach

statistical significance. So, this is

sort of the inverse of what we see with

maca where there do seem to be increases

in testosterone which would predict that

there would be increase in libido. In

this case, in this was post-menopausal

women, there was no increase in libido.

There was an increase in testosterone. I

mention it only because there might be

instances in which people want to

increase their testosterone. It does

seem that tribulus at least in that

population is capable of doing that. Now

there's a separate study that was done a

double blind study uh lasting anywhere

from 1 to 6 months that had a clear and

significant increase in libido. Now,

this was taking six grams, so that's six

6,000 milligrams of tribulus root for 60

days. And it did seem to increase

various aspects of sexual function. I

think more studies are certainly needed,

but these three substances slash

supplements, maca, Tonga Ali in

particular, Indonesian Tonga Ali, and

Tribulus can indeed create significant

increases in sexual desire. and in some

cases by adjusting the testosterone and

estrogen system. In some cases not by

adjusting the testosterone and estrogen

system again pointing to the complexity

of neurochemicals and features that

adjust things like libido aka desire. So

we covered a lot of material today

related to desire, love and attachment.

And yet I acknowledge that it is not

exhaustive of the vast landscape that is

the psychology and biology of desire,

love, and attachment. Nonetheless, I

hope that you found the information

interesting and hopefully actionable in

some cases toward the relationships of

your past, of present, and potentially

for the relationships of your future.

Thank you for joining me for today's

discussion about desire, love, and

attachment. And last, but certainly not

least, thank you for your interest in

science.