"Sexy Times Call For Sexy Measure" | CAS Inquire
Tierney Lorenz of the Department of Psychology gave the talk for CAS Inquire Feb. 22.
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- [00:00:02.240]Good evening, I'm Dr.
- [00:00:03.800]Taylor Livingston,
- [00:00:04.840]the director of the College of Arts
and Sciences Inquire program.
- [00:00:08.960]Thank you all for joining us tonight.
- [00:00:12.080]We had the cozy comfort of Zoom
or joining us in person
- [00:00:16.840]and braving the blistering cold outside.
- [00:00:21.080]Tonight's installment
of the spring semester CAS Inquire
- [00:00:24.560]lecture series is based upon
the theme Pain and Pleasure.
- [00:00:29.000]Although the topic for the series
was chosen before the global pandemic,
- [00:00:33.400]it's particularly apt
given our current cultural moment
- [00:00:37.400]and celebrating recently the anniversary
of the second year of a global pandemic.
- [00:00:44.160]The entire series is structured
around these lectures,
- [00:00:47.760]allowing students, faculty, staff
and the wider public
- [00:00:52.160]the opportunity to investigate
how we, as individuals and society
- [00:00:57.760]understand the concepts
of pain and pleasure
- [00:01:00.880]and how their perceptions shape
and are reflected by human behavior.
- [00:01:07.360]Additionally, it creates the opportunity
to learn about the fascinating research
- [00:01:12.280]the faculty members in the College of Arts
and Sciences are conducting
- [00:01:16.360]and enable students
to see the necessity of multi trans
- [00:01:21.160]and interdisciplinary insights
to understand human phenomena and actions.
- [00:01:27.600]Tonight's lecture by Dr.
- [00:01:29.280]Tierney Lorenz, assistant
professor of psychology
- [00:01:32.280]in the Department of Psychology
and also in the Center for Brain
- [00:01:37.240]Biology and Behavior, explores
the discom, the aspects of pleasure,
- [00:01:43.440]sexual arousal and,
while perhaps not openly discussed,
- [00:01:48.520]is a vital aspect of women's, mental
and physical health.
- [00:01:53.520]Dr. Lorenz was a postdoctoral fellow
at the Kinsey Institute
- [00:01:58.120]for Research in Sex, Gender
- [00:02:01.560]and here at Nebraska.
- [00:02:04.360]She is the director of the Women Immunity
and Sexual Health Lab, which investigates
- [00:02:09.720]the connection between sexual behavior,
women's immune system and hormone levels.
- [00:02:16.240]In addition to this research, the lab
also helps women with mental
- [00:02:20.560]and physical health conditions
lead sexually fulfilling lives.
- [00:02:25.000]Please join me in welcoming Dr. Lorenz.
- [00:02:51.120]OK, they told me that
- [00:02:54.360]I still have to use a mic,
even though I'm a New Yorker.
- [00:02:58.360]OK, well, thank you all for braving
the cold to be with us today.
- [00:03:02.720]I'm absolutely thrilled
to be here to get to close out
- [00:03:04.920]what has been a really amazing lecture
series on pleasure and pain.
- [00:03:10.320]And thank you, Dr.
- [00:03:11.080]Livingston, for that lovely introduction.
- [00:03:13.920]As you mentioned, I am an assistant
professor in the Department of Psychology
- [00:03:17.280]and the Center for Brain Biology
and Behavior, CB three
- [00:03:20.280]and the Women Immunity
and Sexual Health Lab,
- [00:03:22.880]which has a couple of representatives
here in the front row. Thanks for coming!
- [00:03:26.880]Is within the clinical psychology
and neuroscience and behavior areas.
- [00:03:31.120]Today, I'm going to be talking
a little bit about some of our recent work
- [00:03:34.120]on sexual arousal, desire, pleasure
- [00:03:36.920]and how that might influence
women's, mental and physical health.
- [00:03:41.280]So as a quick heads up, I'm
guessing that if you are listening today
- [00:03:47.400]that you know that
we're going to be talking about sexuality.
- [00:03:51.080]But I do want to warn folks that I am
going to be using scientifically accurate
- [00:03:55.720]but explicit language to describe sexual
anatomy and sexual processes.
- [00:04:00.760]So if you're listening at home
- [00:04:02.000]and you have some little ones
- [00:04:03.080]in the background, now's a great time
to get those headphones.
- [00:04:07.120]I also want to mention
that I'm going to be talking
- [00:04:09.720]about some of our work
with survivors of sexual trauma
- [00:04:12.840]and how their minds and bodies
respond to sexual stimuli post assault.
- [00:04:17.040]I recognize that
that can be a really sensitive topic
- [00:04:19.280]for some people, so I will give a heads up
before we get into those sections.
- [00:04:22.720]There will be two of them
- [00:04:24.000]and each one is going to take about two,
two and a half minutes or so.
- [00:04:26.800]So if you want to tap out during
the sessions, you will get fair warning.
- [00:04:31.200]So let's start with the very broadest
question, which is why study sex at all?
- [00:04:37.200]Why study sexual pleasure and why
specifically are we interested in the fun
- [00:04:41.840]bits? I get this question a lot, usually
right after the loading screen fail face.
- [00:04:49.120]A you study what
- [00:04:52.520]because people have a really hard time
wrapping their heads around the idea
- [00:04:57.080]that a scientist
would want to take something
- [00:04:59.880]that's so taboo and so personal
and quantify and analyze it.
- [00:05:04.240]But it's that tension that makes
sexual pleasure so interesting to study.
- [00:05:08.640]Some of the other talks in this series
of really nicely
- [00:05:11.200]highlighted the ways
in which we think about pleasure and pain
- [00:05:15.360]and how that in turn helps us
to understand who we are as people
- [00:05:20.520]and as a society now as a neuroscientist.
- [00:05:23.800]I would argue that sexual pleasure
is one of the most important aspects
- [00:05:28.320]of pleasure to understand
because it shaped the evolution
- [00:05:33.040]of our sexual reward systems or of our
reward processing systems more broadly.
- [00:05:37.680]Sexual pleasure is considered one of the
primary rewards, meaning that it's innate.
- [00:05:41.880]It's sort of built into
how our reward processing centers work.
- [00:05:46.800]Primary rewards refer back
to those rewards
- [00:05:50.280]that we experience when engaging
with our most basic needs, right?
- [00:05:53.320]So the pleasure that we get from eating
or from relief, from physical discomfort.
- [00:05:58.480]But sex is really special
among the primary rewards because
- [00:06:04.240]although reproduction is necessary
for the survival of the species,
- [00:06:08.640]it's not necessary
for the survival of any individual
- [00:06:12.080]and in fact can come at really great cost.
- [00:06:15.120]And so evolution has favored
- [00:06:19.200]whose sexual motivation and reward
processing is sensitive
- [00:06:24.040]to the environmental context
is sensitive to those times
- [00:06:28.480]when resources are good
and you can afford to invest
- [00:06:32.320]in reproduction and in humans
who are an incredibly social animal.
- [00:06:38.160]That environment,
when we talk about being sensitive
- [00:06:41.000]to the environment, that environment
includes the social environment.
- [00:06:44.800]So understanding sexual pleasure
- [00:06:48.680]gives us a really important key
- [00:06:52.040]some of these evolutionary tradeoffs
that we make between
- [00:06:56.320]investing now in a current reproduction
versus delaying later.
- [00:07:00.760]And that, in turn,
tells us a great deal about the mechanisms
- [00:07:05.560]by which our minds, our bodies
and our relationships
- [00:07:09.960]are responsive to each other
and to the environment .
- [00:07:13.040]It provides a really excellent model
of those broader systems.
- [00:07:16.960]So for example, as we're going to see
throughout the talk today,
- [00:07:20.320]our bodies pay attention
to our sexual activity
- [00:07:23.440]and our sexual arousal levels in order
to regulate the action of our hormones,
- [00:07:28.200]of our autonomic nervous system
and on of our immune system.
- [00:07:33.480]And moreover, the
ways that we experience sexual pleasure
- [00:07:37.600]have also shaped the evolution
- [00:07:39.160]of how we relate to each other
in our most intimate relationships.
- [00:07:43.440]There's been a lot of really great work
that suggests that when it is shared,
- [00:07:47.120]sexual pleasure is one of the most
- [00:07:49.920]tight bonds that people can experience
- [00:07:52.080]one of the strongest binding forces
within a relationship.
- [00:07:55.360]And evolution knows this and has used this
to kind of shape the incredible
- [00:07:59.680]diversity of different social systems
that we see across the globe, right?
- [00:08:05.640]Many different kinds of intimate
relationships that vary in their structure
- [00:08:10.240]and their form, but always come back
to this sort of foundational
- [00:08:15.120]framework of shared sexual pleasure.
- [00:08:17.280]So if we don't understand
how we experience sexual pleasure,
- [00:08:21.280]why we experience that, the ways
that people use it
- [00:08:23.520]in their sexual relationships,
then we're really missing out on this kind
- [00:08:26.640]of key foundational piece to understanding
the diversity of human relationships
- [00:08:31.000]and the very nature of intimacy itself.
- [00:08:34.480]As a real quick aside, here
I do want to be mindful
- [00:08:37.800]of the ace and Arrow folks
who are listening in.
- [00:08:41.080]I realize that it could sound like
I'm dismissing people who don't experience
- [00:08:45.360]sexual pleasure and don't particularly
want to is somehow being unnatural.
- [00:08:48.880]And I do recognize that historically
there's been a lot of marginalization
- [00:08:52.600]from science that has generally either
excluded asexual folks or
- [00:08:58.760]treated asexuality
as some sort of pathology.
- [00:09:01.720]But I think that there is incredible value
- [00:09:04.760]your experiences, too,
because it's a sexuality.
- [00:09:09.040]And although sexuality evolved together
and understanding both of these
- [00:09:13.680]gives us a much better understanding
of the broad range and spectrum
- [00:09:17.640]of human sexual experience,
- [00:09:20.080]and it helps us to understand
these complex ways that sexual pleasure
- [00:09:23.320]shapes our minds, bodies
- [00:09:26.560]So all of this is
my pitch to you about why
- [00:09:28.760]sexual pleasure is interesting
from the perspective of a neuroscientist.
- [00:09:31.840]But I'm also a clinical health
psychologist, and from that perspective,
- [00:09:36.000]I'm really interested
in sexual pleasure and the ways in
- [00:09:38.760]it's rooted in promoting well-being.
- [00:09:41.840]So when we have good models of how
the mind, the body and relationships work
- [00:09:45.360]together, then we can act on those systems
to promote. Well-Being.
- [00:09:50.080]And when I talk about this,
people are usually quick
- [00:09:52.360]to think about reproductive health,
and certainly sex
- [00:09:56.040]is really important
for understanding reproductive health.
- [00:09:59.200]So for example, if we're really serious
- [00:10:02.040]sexually transmitted infections,
- [00:10:03.800]we have to understand the context
in which people get
- [00:10:07.200]sexually transmitted infections,
which are sexual context, right?
- [00:10:10.960]People don't engage in sex
in order to expose themselves to risk.
- [00:10:14.920]They engage in sex because it's fun.
- [00:10:16.800]And so if we don't understand that fun,
then we're really missing a key
- [00:10:20.280]part of being able to help people
to reduce their risks in a meaningful way.
- [00:10:26.080]So if we're not serious
about sexual pleasure,
- [00:10:28.560]we're really not going to get very far
when it comes to reproductive health.
- [00:10:32.480]But as I just argued, sexual
pleasure is really foundational
- [00:10:36.480]to understanding
how our minds and bodies work.
- [00:10:39.720]So a lot of the work from
my lab looks at sexual
- [00:10:42.840]wellbeing in folks with mental
or physical health conditions, as Dr.
- [00:10:46.320]Livingston mentioned.
- [00:10:47.840]But that's not just because
we want to promote health
- [00:10:50.600]in these populations,
although we certainly do,
- [00:10:53.120]but also because we see sex
as a health behavior
- [00:10:56.480]that can be used to promote well-being
and reduce the risk of disease.
- [00:11:01.200]So for example, today
we're going to be talking
- [00:11:03.640]about how sexual activity interacts
- [00:11:07.360]and how that in turn, could potentially
influence people's risk for inflammatory
- [00:11:11.880]inflammation related conditions
such as depression or heart disease.
- [00:11:17.280]And then finally, as a teacher
and a mentor to the next generation
- [00:11:21.520]of scientists and clinicians, I'm
committed to training folks in the bio.
- [00:11:25.320]Psychosocial model of health
and sexual science is a really great way
- [00:11:28.840]to get at this because sex is inherently
a biological phenomenon,
- [00:11:33.440]a psychological experience
and a social context.
- [00:11:37.480]So the science of sexuality really helps
us to be able to train that mindset
- [00:11:41.120]in the next generation, and I'm excited
to see some of that next generation here.
- [00:11:45.600]So that's my pitch
for why we need to study
- [00:11:49.320]sexual pleasure in the first place.
- [00:11:51.240]But given that importance,
how do we go about quantifying
- [00:11:55.360]such a nebulous variable?
- [00:11:57.880]So generally speaking, psychologists
- [00:12:01.320]are interested in people's
thoughts, feelings and behaviors.
- [00:12:04.960]So this means that
in the context of sexuality,
- [00:12:07.200]we might be interested in studying
people's behavior, such as their patterns
- [00:12:10.840]of sexual activity,
both partners and solitary.
- [00:12:14.760]We might be interested in their sexual
feelings, their subjective experiences
- [00:12:18.280]of their own desire and pleasure, as well
as their positive and negative emotions.
- [00:12:23.160]When it comes to cognition, we might be
interested in people's patterns
- [00:12:26.560]of sexual motivation and interest,
but also their attention to sexual cues
- [00:12:31.440]or conversely, their distraction
or dissociation from those cues,
- [00:12:35.520]as well as the way that we think
- [00:12:37.240]about our own sexuality
that is our sexual self schema.
- [00:12:41.280]Now, none of these broad categories
are things that are particularly unique
- [00:12:45.400]to sexuality scientists.
- [00:12:46.640]There's lots of tools that psychologists
use to measure schemas or attitudes or
- [00:12:51.280]people's health behaviors.
- [00:12:53.440]And certainly, we
use all of these tools in my lab.
- [00:12:55.640]But something that's unique to our lab
and to sexual psycho physiology
- [00:12:59.440]is also looking at the ways
that people's minds influence
- [00:13:02.880]what their bodies do
during the sexual response and vice versa.
- [00:13:06.240]That is what we call sexual
arousal and orgasm psycho physiology.
- [00:13:11.800]So thinking about
what are the different aspects,
- [00:13:16.440]what are the ways in which our minds
influence what our bodies do during sex?
- [00:13:21.080]first and foremost, we have to think about
sexual arousal as an emotional response.
- [00:13:27.040]So like all emotional responses,
- [00:13:30.400]arousal is going to activate certain parts
of the autonomic nervous system.
- [00:13:35.440]So I'm going to take
- [00:13:36.000]a little step back here
and do some kind of psych 101 refreshing
- [00:13:40.360]in our nervous system, right?
- [00:13:42.120]We have different parts
of the nervous system.
- [00:13:43.720]We have the central nervous system.
That's your brain, your spinal cord.
- [00:13:46.840]And that's what most people think of
when they think of the nervous system.
- [00:13:49.360]But there's this whole other branch
- [00:13:50.960]called the autonomic nervous system, and
this is the part of your nervous system
- [00:13:55.240]that helps to kind of coordinate action
across different organ systems
- [00:14:00.160]and communicate with your central nervous
system in response to particular stimuli
- [00:14:04.560]that you need to either
activate or rest and relax.
- [00:14:07.440]So the autonomic nervous system
has the parasympathetic nervous system
- [00:14:10.840]and the sympathetic nervous system
as kind of buddies that operate together
- [00:14:15.200]the parasympathetic nervous system.
This is your rest and relax system.
- [00:14:18.440]This is the system
that's predominantly active
- [00:14:20.360]most of the time when you're
a healthy person, and the sympathetic
- [00:14:23.400]nervous system is sometimes
called the fight or flight system.
- [00:14:27.200]It's a little bit of a misnomer, though,
because it would be more accurate to say
- [00:14:30.120]it's your activate
- [00:14:31.320]and get energized system because with the
sympathetic nervous system does is , it
- [00:14:35.080]constantly scans
the environment for cues that you need
- [00:14:38.560]to react to a particular stimulus
you need to activate.
- [00:14:42.360]And when it notices
those cues, it activates
- [00:14:44.640]a whole bunch of different systems
all across the body in.
- [00:14:48.360]Order to be able
to mobilize energy resources
- [00:14:51.480]and get you ready to do something
in response to that stimulus.
- [00:14:55.120]So all emotions are going to generate
some sympathetic activation.
- [00:15:01.080]That's part of what makes
- [00:15:03.600]emotional responses feel activating
fuel energizing right now.
- [00:15:08.960]That's true if you get turned on
or if you're happy or you're angry, right
- [00:15:12.960]that you're sympathetic, nervous system
- [00:15:14.200]is going to kick on a little bit
for any kind of emotional response.
- [00:15:18.680]What's really interesting and unique
about sexual arousal
- [00:15:22.360]as an emotional response
is the relationship that we have between
- [00:15:27.800]this autonomic nervous system activation
and the stress response.
- [00:15:32.720]So when your sympathetic nervous
system kicks in, right when that fight
- [00:15:36.440]or flight system kicks
in, when it gets to the higher levels
- [00:15:39.440]of its activation,
it can trigger a broader stress response.
- [00:15:44.000]When we think about stress,
we often think about the responsiveness
- [00:15:46.920]of our hormonal stress
responses like cortisol, right?
- [00:15:50.680]And so when you feel really,
really strong emotional responses,
- [00:15:55.200]whether they're happy or not happy,
whether they're good or bad,
- [00:15:59.520]if they get to very high levels
of sympathetic activation
- [00:16:02.200]that can generate a stress response,
that's part of why it feels so draining
- [00:16:06.120]to have really strong emotions, even
if those strong emotions are positive.
- [00:16:11.560]But this is what's really unique
about sexual response
- [00:16:16.000]is that when sympathetic activation
happens in the context of sexual arousal,
- [00:16:21.240]we don't see that stress triggering
- [00:16:23.720]right at very high levels of arousal
and particularly at orgasm
- [00:16:27.760]when we see really high levels
of sympathetic activation.
- [00:16:31.360]We see a significant drop
in cortisol levels.
- [00:16:35.000]Now, from a scientific perspective,
this is really fascinating
- [00:16:38.000]because it says that there's
something unique about sexual arousal
- [00:16:42.080]that allows the body
to decouple this activation
- [00:16:46.080]of the autonomic nervous system
with a broader stress response.
- [00:16:49.720]And if we can just understand
that decoupling system,
- [00:16:53.880]we might be able to harness
that to be able to help
- [00:16:57.320]to retrain the stress system in people
whose bodies are particularly responsive
- [00:17:02.720]to autonomic arousal,
such as people with anxiety disorders.
- [00:17:06.680]So as one example of this line of research
- [00:17:10.320]from my lab, we've looked at sympathetic
- [00:17:14.240]activation and various
different measures of genital arousal.
- [00:17:18.040]And here we're talking
about vaginal genital arousal.
- [00:17:20.720]So this vigorous from a large meta
analysis that we conducted
- [00:17:24.400]a meta analysis is when you take data
from a bunch of different studies
- [00:17:27.880]that study something similar
and you put them all together
- [00:17:30.040]into one big data set to try to come up
with some stronger conclusions.
- [00:17:33.720]So in this study, we looked at changes in
heart rate variability,
- [00:17:36.840]which is a measure
of this autonomic balance, right?
- [00:17:39.840]So in the kind of more blue
side of the screen here,
- [00:17:42.840]we're seeing more increasing
- [00:17:46.160]That means lower sympathetic activation.
- [00:17:48.640]And on the red side of the screen, here
- [00:17:50.240]we're seeing increasing
- [00:17:52.920]This is in response to a sexual fell
- [00:17:56.400]on the y axis. We have changes in genital
arousal and in this particular case,
- [00:18:00.280]we're looking at changes in vaginal blood
flow in response to a sexual thing.
- [00:18:03.760]I'll get into how we measure that
in just a moment.
- [00:18:06.440]But as you can see, there's
this really interesting curvilinear
- [00:18:09.080]response between autonomic arousal
and subsequent genital arousal. Right?
- [00:18:14.800]What's even more interesting
is that when we get to these
- [00:18:17.400]really high levels
of sympathetic activation, even though
- [00:18:21.200]there's maybe lower
levels of absolute genital arousal,
- [00:18:25.800]we're not seeing that same stress cascade.
- [00:18:29.560]So really kind of interesting
- [00:18:32.560]decoupling happening here
and something that would be very difficult
- [00:18:36.520]to look at if we weren't measuring genital
- [00:18:40.520]. As a heads up, I had mentioned that
there were going to be a couple of moments
- [00:18:43.600]when I was going to talk about
sexual trauma, and this is one of those.
- [00:18:46.160]So again, if you need to step out,
now's the time to step out.
- [00:18:48.680]We'll see you in
about two and a half minutes.
- [00:18:52.840]So one of the reasons
that we're really interested
- [00:18:54.840]in this kind of decoupling response
is because we're really interested
- [00:18:58.520]in the ways that this plays out
in sexual trauma survivors.
- [00:19:01.920]So in folks who have experienced
sexual trauma, a sexual stimulus is
- [00:19:08.120]has a kind of a push pull to it
- [00:19:10.600]because on the one hand, a sexual stimulus
still signals the possibility of reward.
- [00:19:15.280]Right. Sex can still be quite pleasurable
and fun for folks, even post assault.
- [00:19:20.800]But at the same time,
that exact same stimulus is now
- [00:19:24.400]also being coded as a stressor.
- [00:19:27.560]So you have this really interesting
- [00:19:31.160]of the sexual response and the stress
response system at the same time.
- [00:19:35.160]In parallel, that
decoupling sort of breaks
- [00:19:38.160]down in the context
of sexual trauma survivorship.
- [00:19:41.440]And that's also really interesting
because it tells us a great deal more
- [00:19:45.160]about the potential after effects
of sexual trauma and the ways
- [00:19:49.280]in which sexual trauma really uniquely
activates the stress response system,
- [00:19:53.720]even in the face of what would otherwise
be a very pleasant, rewarding you.
- [00:19:59.280]And so understanding that, too has some
really powerful implications for therapy
- [00:20:04.880]and for treating sexual trauma survivors
- [00:20:07.160]and helping them to be able
to experience reward again.
- [00:20:10.800]So in a set of studies, we've looked at
- [00:20:14.280]sexual trauma survivors and folks
who don't have a trauma history.
- [00:20:18.080]And what we found is that among women
who have a sexual trauma history,
- [00:20:22.400]particularly a history of childhood
sexual abuse, we see
- [00:20:25.840]we tend to see higher
- [00:20:28.640]And it gets up to that level
where we start to see the triggering
- [00:20:31.440]of the stress response that we don't see
in folks who don't have a trauma history .
- [00:20:36.040]In fact, folks without a trauma history,
- [00:20:38.040]we tend to see relatively lower
- [00:20:41.200]but that's actually associated with higher
arousal levels simply because it kind of
- [00:20:44.800]puts them into this more moderate level
of sympathetic activation.
- [00:20:48.160]And then in folks
- [00:20:48.880]who don't have a trauma history but
who say that they have sexual problems,
- [00:20:53.600]we actually see really low activation
of sympathetic activity.
- [00:20:57.640]And this kind of reflects
the sort of broader issue
- [00:21:00.800]with not feeling activated,
not feeling energized, not feeling excited
- [00:21:04.960]and engaged during sex.
- [00:21:07.080]So it kind of nicely reflects
that across the board. OK.
- [00:21:10.960]Those of you who tapped out
for the sexual trauma piece, welcome back.
- [00:21:16.000]So coming back to
that broader picture, right?
- [00:21:18.000]So going beyond the idea that
sexual arousal is an emotional response,
- [00:21:23.240]there's 1,000,000 other things that happen
to the body during sex that we could
- [00:21:28.040]potentially measure and do measure
in sexual psycho physiology.
- [00:21:31.840]And I will note,
not everything on this list
- [00:21:33.520]I'm about to present is stuff
that we do necessarily in our lab.
- [00:21:37.040]But it is definitely things
that we collaborate with, with other labs
- [00:21:40.200]and is used in the broader
field of sexual psycho physiology.
- [00:21:43.840]So like I mentioned, we're
really interested in autonomic arousal.
- [00:21:48.400]At its core, sexual arousal is a
- [00:21:51.280]a process of blood
flow rate is a shift of blood flow
- [00:21:55.160]to the genitals in response
to a particular cue
- [00:21:58.040]that the brain identifies
as sexual or erotic.
- [00:22:01.680]And so when we're studying blood flow,
- [00:22:03.640]there's all different pieces to this
that we can study.
- [00:22:05.480]We can look at the direction
of blood flow into the genitals,
- [00:22:09.680]which we can measure directly
using ultrasound or Photoshop.
- [00:22:12.920]This mammography, both of which are tools
that are going to measure the movement
- [00:22:16.080]of blood flow or volume of of blood
that pools into a tissue.
- [00:22:22.240]So we can look at this
- [00:22:23.080]directly, but we can also look
at the after effects of that process.
- [00:22:26.840]So if you think about the last time
that you blushed,
- [00:22:30.160]I'm going to call you out here
- [00:22:31.120]because you were talking about
how every time I talk,
- [00:22:33.280]every time I give a talk,
you always blush.
- [00:22:35.000]So right now in Rick's cheeks,
probably there's a little bit of blood
- [00:22:39.280]that was circulating close to his core and
is now coming up into his cheeks, right?
- [00:22:45.680]And it's causing some change in color
- [00:22:47.440]and it's causing some change,
and he is giving me a thumbs up.
- [00:22:50.000]That's what's happening. So, right,
- [00:22:52.080]so when we move blood
from the central part of the body
- [00:22:56.320]into the periphery, it changes the heat
and the color of those tissues.
- [00:23:00.680]And those two we can measure directly
using thermal graphic measurements.
- [00:23:06.080]There is, of course, erection,
which is probably
- [00:23:08.200]what popped into most people's heads
when I said measuring sexual arousal.
- [00:23:12.240]So we can measure
the physical firmness of the tissues.
- [00:23:14.800]But more often we're changing.
- [00:23:16.120]We're looking at changes in size
or the rigidity of the tissue,
- [00:23:20.320]and that's measured using this placement
so we can put a displacement chamber
- [00:23:23.680]over a tissue bed
and that chamber will be filled with air.
- [00:23:28.360]And as the tissue changes in shape or size
- [00:23:31.640]that will push the air
out of that chamber,
- [00:23:33.640]and we can look at the amount of air
- [00:23:34.920]that is being pushed out as a reflection
of the degree of the erection,
- [00:23:38.760]where similarly there are
soft rings that are filled
- [00:23:41.520]with liquid that you can place over
or around a tissue.
- [00:23:44.680]And again, as it becomes as it changes
in shape, as it becomes more rigid,
- [00:23:48.400]it will push against that soft ring
and it will pull some of the liquid.
- [00:23:52.280]Out of that ring, and we can measure
just the amount of change in liquid
- [00:23:56.040]in order to be a reflection
of the degree of erection of that tissue.
- [00:24:01.800]So in the uterus
and vagina, during arousal,
- [00:24:05.440]there are some really interesting
protective mechanisms that occur
- [00:24:09.600]to help protect the cervix
and the internal organs from penetration.
- [00:24:14.320]And so during arousal,
as the body becomes more aroused,
- [00:24:17.720]the vagina will actually stretch long
and the uterus will kind of retreat up
- [00:24:21.520]into the abdomen,
- [00:24:22.800]and that both of those responses
will increase the pressure
- [00:24:25.640]within the vaginal canal.
- [00:24:27.240]And so we're able to measure the change
in the amount of pressure
- [00:24:30.560]within the vaginal canal,
either by using force plates
- [00:24:34.760]or by looking at things in MRI.
- [00:24:36.880]So by doing direct imaging, they're
- [00:24:40.080]in a manner similar
to how the uterus and vagina
- [00:24:43.520]change their shape in order
as a protective response for penetration.
- [00:24:49.000]Similarly, the scrotum
will also change its shape.
- [00:24:52.440]And so this is essentially
to kind of protect it from harm
- [00:24:57.280]if it's being moved about
or if it's being pressed up another body.
- [00:25:01.320]So we can look at the changes
in skin tension or elasticity
- [00:25:05.080]as a function of the degree of arousal.
- [00:25:10.080]Excuse me, something that
we're really interested in in my lab is
- [00:25:13.760]the way that arousal changes lubrication,
vaginal lubrication in particular.
- [00:25:18.400]So there's lubrication that occurs across
genital types, not just in vaginas, but
- [00:25:24.160]we can look at the amount of lubrication
that's actually produced during arousal.
- [00:25:29.120]So just the sheer amount of moisture.
- [00:25:30.640]But what's even more interesting is
that there are some
- [00:25:32.480]pretty significant changes
in the composition of that lubrication
- [00:25:36.360]in terms of its acidity, its protein
content, the presence of certain
- [00:25:40.040]immune parameters
or endocrine factors, hormones.
- [00:25:43.880]So, for example, at baseline at rest,
- [00:25:47.840]a healthy vagina is going to have
a moderately acidic p h.
- [00:25:52.400]It is precisely the age of a
pinot noir wine.
- [00:25:57.240]Good luck with trying
to get that packed out of your mind
- [00:26:00.040]the next time that you go to
a wine bar. You're welcome.
- [00:26:03.560]And as the process of arousal unfolds,
- [00:26:06.920]that or that lubrication is going
to become very slightly more basic.
- [00:26:10.960]And so we're able to actually measure
the changes in p h by
- [00:26:14.000]just handing off a P H testing strip
to be able to observe the ways
- [00:26:18.880]in which arousal is changing
that lubrication dynamic.
- [00:26:23.400]So in addition to the changes
in muscles and blood
- [00:26:25.960]vessels and glands in the genitals,
- [00:26:27.560]there's also changes in the nerve beds
that generate sexual sensation.
- [00:26:31.720]And we can measure this as well.
- [00:26:33.440]So there's a really strong increase
in sensitivity to fine touch and pressure.
- [00:26:39.040]And at the same time,
there's a significant decrease
- [00:26:41.880]in pain sensitivity
that is an increase in pain tolerance.
- [00:26:45.760]What's really amazing is that the pain
tolerance that we see in these nerve beds
- [00:26:52.280]during orgasm is actually
- [00:26:54.200]among the highest unmedicated
pain tolerances that have been recorded.
- [00:26:58.880]Now, from an evolutionary perspective,
this makes a ton of sense because we are
- [00:27:03.200]subjecting those tissues to extraordinary
forces during sexual arousal, right?
- [00:27:08.600]They are changing their shape,
they're changing their structure,
- [00:27:12.000]they're being moved
about with great vigor.
- [00:27:14.280]And so it would make a lot of sense
that we would have evolved and adapted
- [00:27:18.320]to have increased pain tolerance
in those tissues during this time.
- [00:27:22.720]But from a scientific perspective,
this is really fascinating
- [00:27:25.640]for understanding
pain perception itself, right?
- [00:27:28.920]Understanding the way
that the brain processes pain
- [00:27:31.760]and and interacts
with other emotional sensations
- [00:27:34.800]to be able to either
increase or decrease our pain tolerance.
- [00:27:38.360]So, for example, there's
some really amazing work that's happening
- [00:27:41.560]right now looking at people
with chronic pain conditions
- [00:27:46.160]and using orgasm therapies
to retrain how the brain perceives pain
- [00:27:51.840]in order to be able to help
treat that chronic pain.
- [00:27:55.160]I don't want to oversell that work.
- [00:27:56.400]It is still definitely
it's in its infancy,
- [00:27:58.920]but I think it's really fascinating
and kind of underscores
- [00:28:01.240]the fact that understanding
- [00:28:02.560]these processes tells us a great deal
about how the brain works
- [00:28:07.320]when it comes to orgasm.
- [00:28:09.320]one of the things we're interested in is
the not just the rhythmic contractions of
- [00:28:15.840]that happen during orgasm,
- [00:28:17.880]but the specific patterns
of those rhythms, right?
- [00:28:20.920]So during orgasm,
there are contractions that occur within
- [00:28:25.120]the genitals that kind of spread out
into the pelvic floor.
- [00:28:28.040]And there's some evidence
that in people who are pregnant
- [00:28:32.160]as they get closer and closer
to their delivery date,
- [00:28:36.760]that the pattern of rhythm
that we see in during
- [00:28:41.080]orgasm gets closer and closer to that
which is coordinated during delivery.
- [00:28:45.680]So there's this hypothesis
that the body is using orgasm
- [00:28:50.400]to train the pelvic floor
not only in the extraordinary strength,
- [00:28:54.560]but also the specific rhythms
that are going to be necessary
- [00:28:57.480]for a successful delivery.
Really fascinating stuff.
- [00:29:01.160]And then finally, there are these specific
brain activation patterns
- [00:29:05.160]that are associated with our subjective
experience of our own sexual response
- [00:29:09.920]and perhaps not surprisingly, sexual
arousal and orgasm are associated
- [00:29:13.800]with a significant decrease
in brain activity,
- [00:29:17.080]particularly in the higher order
areas of the brain.
- [00:29:20.920]This is often why I joke that I am a below
the neck neuroscientist because if the
- [00:29:24.960]brain's doing its job during orgasm,
not a lot going on above the neck.
- [00:29:31.920]So that was a lot.
- [00:29:34.720]But hopefully it gives you an idea of some
of the complexity of these measurements
- [00:29:37.720]and the wealth of information
that we can gather if we actively look
- [00:29:41.480]for what happens
during the sexual response.
- [00:29:47.000]So what does that all get us?
- [00:29:48.360]Let's dove into a little bit
- [00:29:49.640]of our research on inflammation
and women's sexual response.
- [00:29:54.560]So a shout out here
to my graduate student on a list
- [00:29:58.080]who is in this picture showing off her
amazing technical skills in the wet lab.
- [00:30:01.440]But she's also a very talented
- [00:30:03.640]and she designed this figure
for one of our recent reviews.
- [00:30:06.920]So in the whish lab,
we're really interested in the ways
- [00:30:09.600]that the immune system and in particular
the inflammatory system
- [00:30:12.800]interacts with women sexual desire,
- [00:30:16.320]Inflammation is a really significant
contributor to a lot of different
- [00:30:20.000]chronic health conditions
because it has interactions
- [00:30:24.040]with a lot of different systems
throughout the body.
- [00:30:26.920]So, for example,
the inflammatory system has communication
- [00:30:30.160]with the endocrine system with hormones,
and it regulates and is regulated
- [00:30:35.120]by the expression of reproductive hormones
and stress hormones.
- [00:30:38.160]two things we're really interested in.
- [00:30:40.080]It's also responsible for coordinating
- [00:30:43.520]certain certain aspects of cardiovascular
function, such as and can
- [00:30:47.160]contribute to cardiovascular pathologies
such as heart disease.
- [00:30:51.280]So insofar as we're interested
in arousal, right,
- [00:30:54.560]we're really interested in blood flow.
- [00:30:56.040]And so understanding
inflammation is important there, too.
- [00:30:59.200]And then there's also direct
effects of inflammation on the brain,
- [00:31:03.040]on the central nervous system, changing
the way that the brain processes reward.
- [00:31:07.880]So all of these things
not surprisingly contribute to women's
- [00:31:11.000]sexual arousal, desire and pleasure,
and potentially vice versa.
- [00:31:15.760]So I first got interested in this question
of the interaction
- [00:31:19.080]between sexuality and inflammation
- [00:31:21.400]when I saw the results from
the biological study about ten years ago.
- [00:31:25.040]Now, it seems like yesterday.
- [00:31:27.160]So this was a study that was conducted
by the National Institutes of Child
- [00:31:30.400]Health and Human Development.
- [00:31:32.160]And in this study,
they followed 259 women over the course
- [00:31:36.520]of several menstrual cycles and measured
multiple times throughout their menstrual
- [00:31:40.600]cycles, a variety of different hormones
and immune factors.
- [00:31:44.240]And in this particular aspect
of the study, they were really interested
- [00:31:47.320]in this particular marker of inflammation
called C-reactive protein, or CRP.
- [00:31:52.280]A CRP is a really useful marker
of the aspects of inflammation
- [00:31:57.000]that can contribute to vascular pathology,
- [00:32:00.080]which in turn can contribute
to the risk for heart disease.
- [00:32:03.280]So this is actually a test
that your doctor can order
- [00:32:06.520]to assess your risk
for getting heart disease later on. Right?
- [00:32:11.240]But the researchers were really interested
- [00:32:14.800]how that measure might change
over the course of the menstrual cycle.
- [00:32:18.800]So here is being depicted
in the dark circles that are filled in.
- [00:32:23.960]And as you can see,
there is a significant change in CRP
- [00:32:27.520]over the course of the menstrual cycle
in these healthy women.
- [00:32:31.040]So we have the highest levels of CRP
or highest levels
- [00:32:33.960]of inflammation around menses.
- [00:32:36.240]And then the lowest levels around the time
of ovulation right around mid-cycle.
- [00:32:40.840]What's more, these researchers found that
if you took exactly the same woman
- [00:32:45.880]and you took her values of CRP at menses,
- [00:32:50.000]the same exact woman might be
- [00:32:52.760]misdiagnosed as having heart disease
if you measured her during menses.
- [00:32:57.320]Then if you measured her
two weeks later during her ovulation.
- [00:33:01.480]So this has really profound implications
- [00:33:04.760]the clinical utility of CRP
as a marker of heart disease.
- [00:33:08.640]But what intrigued me about this was
the rationale that these authors offered
- [00:33:12.560]for why there might be changes in
CRP over the course of the cycle
- [00:33:16.720]in the first place.
- [00:33:17.960]So they hinted that it might be part
of an evolutionary adaptation
- [00:33:22.160]that by reducing the level of inflammation
- [00:33:26.680]that is around the time of peak fertility
that the body might be reducing
- [00:33:31.640]the risk of interference of inflammation
with the chance of conception.
- [00:33:37.040]So this explanation struck me as logical,
but a little bit incomplete,
- [00:33:42.560]because if the body evolved to shift
its immune function
- [00:33:46.840]priorities over the course
of a menstrual cycle
- [00:33:49.880]in order to balance
these offs between conception and
- [00:33:55.360]defending against disease,
- [00:33:57.200]then it would follow that those trade offs
would only be relevant
- [00:34:00.960]for people who could be reproducing
that cycle. Right.
- [00:34:04.320]So if a person is sexually active,
then their chance of conceiving that cycle
- [00:34:10.600]is it's possible they might get pregnant
because they have been sexually active.
- [00:34:14.800]And so it would make sense
that for these people
- [00:34:17.120]that you would see this shift in immune
function over the course of the cycle.
- [00:34:21.200]But in people who are sexually abstinent,
- [00:34:23.600]then the chances
of getting pregnant that cycle are.
- [00:34:27.480]I mean, the pretty low rate,
like the Virgin Mary is pretty much
- [00:34:29.960]the only instance I can think of in
which an absent person got pregnant.
- [00:34:34.600]So barring that, it's real, pretty low.
- [00:34:37.480]And so it really wouldn't make sense
to be engaging with this tradeoff
- [00:34:41.280]if somebody is sexually abstinent.
- [00:34:44.200]So we first started
to look at this hypothesis.
- [00:34:47.600]We first tested this hypothesis
in a sample of about
- [00:34:51.480]30 healthy young college
students here in the US.
- [00:34:55.360]So women provided saliva samples at four
time points throughout their cycle.
- [00:34:59.680]So within the first three day
of their menstrual cycle,
- [00:35:02.720]about a week later during their follicular
phase within 36 hours
- [00:35:07.200]of their ovulation, which is what we call
the Perry ovulatory phase.
- [00:35:11.120]And then one week later,
during their luteal phase,
- [00:35:15.120]women collected their samples,
their saliva samples at home,
- [00:35:17.840]and they tested for ovulation using
urine test strips for luteinizing hormone.
- [00:35:21.960]So we were able to accurately pinpoint
where within the cycle
- [00:35:25.520]they actually ovulating so that we could
match their saliva samples up to that.
- [00:35:29.920]So about half of the sample
was sexually abstinent,
- [00:35:32.720]although I will note that this meant
that they were not sexually partnered.
- [00:35:36.400]This did not necessarily mean that they
didn't engage in masturbation, because
- [00:35:40.400]if you exclude women who masturbate
from a young, healthy college sample
- [00:35:45.200]pretty soon, you
have no one left to study.
- [00:35:47.280]So about half of the other women
were sexually partnered, and of them,
- [00:35:53.360]about half reported having partnered
sexual activity once a week or less.
- [00:35:57.640]That's our low frequency
group, or twice a week or more.
- [00:36:00.360]That's our high frequency group.
- [00:36:02.680]These are not value judgments.
- [00:36:04.120]These are just the median
split of the data.
- [00:36:07.560]So as predicted, the abstinent group
- [00:36:10.040]showed very little change in inflammation
over the course of the cycle.
- [00:36:14.040]And similarly, the low
- [00:36:15.640]frequency of sexual activity group
also showed very little change.
- [00:36:19.560]But among our folks who said
that they had the most sexual activity,
- [00:36:24.520]we saw really significant differences in
inflammation over the course of the cycle.
- [00:36:28.120]And this fits with our broader theory
that this should only really matter
- [00:36:31.320]for people who are more likely
to potentially conceive.
- [00:36:34.440]Right. So we saw much higher levels of
inflammation in the in the menstrual phase
- [00:36:39.400]and then a considerable decrease
around the mid-cycle.
- [00:36:43.120]So this is nice initial support
for our evolutionary adaptation theory.
- [00:36:47.680]But if this truly is
an evolutionary adaptation,
- [00:36:51.560]we should expect to see similar patterns
across cultures and environments.
- [00:36:57.640]And so we then sought to replicate
these findings in a different population.
- [00:37:02.360]And luckily, around this time I was
working with an anthropologist colleague
- [00:37:07.160]who was doing some research in Bolivia
looking at rural Bolivian farmworkers,
- [00:37:12.080]and she was really interested
- [00:37:12.880]in understanding the dynamics
of inflammation in that population
- [00:37:15.880]so radically different
from our UC College students.
- [00:37:19.680]So here's what we found there.
- [00:37:22.040]So in the graph that I'm about to show
in a moment, the dotted lines reflect
- [00:37:27.080]women who were sexually abstinent,
were not sexually partnered, and then the
- [00:37:30.280]solid lines are going to reflect the women
who were sexually partners.
- [00:37:34.200]And you can immediately
see the extraordinary similarity
- [00:37:37.280]to the findings that we had
in the US population.
- [00:37:40.640]So among the abstinent women,
- [00:37:43.200]there's very little change in inflammation
over the course of the cycle.
- [00:37:47.000]And in the partnered women
who are sexually active,
- [00:37:50.120]we saw significantly elevated inflammation
at the premenstrual menstrual
- [00:37:56.360]luteal phase and a significant decrease
around the time of population.
- [00:37:59.600]So the fact that we saw such
- [00:38:01.280]similar results across these two
radically different populations of women
- [00:38:05.200]really provides some additional support
that this is an evolutionary adaptation.
- [00:38:10.360]And what these studies suggest is
that the body is using information
- [00:38:14.320]about one's sexual behavior
to direct the activity
- [00:38:18.800]of the inflammatory system
in really subtle but consistent ways.
- [00:38:23.480]And that, in turn, got us thinking
about some of the other ways
- [00:38:26.640]that sexual activity both regulates and
is regulated by the inflammatory system.
- [00:38:32.520]So we were interested in understanding
how the immune system might moderate
- [00:38:35.840]inflammation to regulate
reproductive investment, and that
- [00:38:41.200]how this in turn could extend
to sexual arousal to desire to pleasure.
- [00:38:46.000]So in other words, the immune system in
the reproductive system are coordinating
- [00:38:50.080]their function in order to make sure
that if sexual activity leads
- [00:38:53.920]to an offspring,
that that investment is really well spent,
- [00:38:56.960]that conception is going to happen
when the body is in this
- [00:39:00.080]maximally receptive state a state of low,
relatively low inflammation.
- [00:39:07.600]Excuse me. So, for example,
if a woman is really currently ill
- [00:39:12.560]or engaging in a recovery response
from an infection or an injury,
- [00:39:17.760]and she's in a state of acutely inflamed
and acutely inflamed state,
- [00:39:22.880]that's not a great time for her
to be investing a lot of energy
- [00:39:26.400]in reproducing in producing an offspring.
- [00:39:29.960]It would be better to delay her
reproduction to when times are better,
- [00:39:33.600]when resources are better
and when her physical body
- [00:39:35.520]is in a better condition to do so.
- [00:39:37.400]And we certainly see this play out
in the form of early
- [00:39:40.240]pregnancy loss in folks
who are experiencing acute illness.
- [00:39:43.680]But as I mentioned at the beginning
of the talk, evolution really favors
- [00:39:46.840]these kind of subtle behavioral
and psychological strategies
- [00:39:50.320]because they allow us
- [00:39:51.920]to dynamically respond to our environment
in a much more flexible way.
- [00:39:55.960]And so we started thinking of the ways
that exposure to inflammation
- [00:40:00.320]might also subtly change
- [00:40:03.280]of their own desire
and pleasure and their sexual reward.
- [00:40:07.400]So in other words, inflammation
might decrease a woman's sexual interest
- [00:40:12.880]and decrease the amount of reward
and pleasure that she experiences
- [00:40:16.880]when she does engage in sex,
and that if that happens on the balance,
- [00:40:22.000]it's going to decrease her
sexual frequency and delay her chance
- [00:40:25.200]of conception to a time when her body is
not in the state of active inflammation.
- [00:40:30.440]And this would be a highly adaptive
response in our evolutionary past.
- [00:40:34.840]So we set out to investigate
this new question by taking another
- [00:40:38.480]look at the data from the study
that I mentioned a moment ago
- [00:40:40.680]where we were following women
over the course of their cycle.
- [00:40:43.400]So over that month, women reported on
- [00:40:46.400]they did a daily diary measure
- [00:40:48.120]on whether or not they had engaged
in any kind of sexual activity that day,
- [00:40:51.520]and if so, how aroused they became, how
much pleasure they experienced and so on.
- [00:40:56.520]And we also measured their CRP levels
and kind of looked at how that mapped
- [00:41:01.680]onto their self-reported sexual pleasure
at different phases throughout the cycle.
- [00:41:08.040]So indeed, we did
see some significant effects here,
- [00:41:11.200]so inflammation was not significantly
related to women's self-reported
- [00:41:15.480]sexual pleasure, either at menses
or in the luteal phase, we didn't expect
- [00:41:19.040]that those are not times when there's
a very high chance of conception.
- [00:41:23.120]It's not zero, but it's very unlikely.
- [00:41:26.200]Surprisingly, there was actually a small
but significant positive association
- [00:41:30.600]between sirup and pleasure
during the follicular phase,
- [00:41:33.880]which is a little bit of a head scratcher,
but might make sense in the context
- [00:41:37.040]of the hormonal responses
that are happening
- [00:41:38.760]during this time
as the body ramps up its estrogen
- [00:41:42.840]during the follicular phase
towards the ovulatory phase.
- [00:41:46.640]It can actually have a slightly
- [00:41:50.800]at the same time that other things are
also driving sexual desire.
- [00:41:55.760]But what was really kind
of the kicker here is that we saw this
- [00:41:58.320]really significant negative relationship
between inflammation and pleasure
- [00:42:03.760]during the ovulatory phase
that is during the time of peak fertility.
- [00:42:07.640]So in other words, if a woman experienced
a higher level of inflammation,
- [00:42:12.400]she reported much lower sexual pleasure
for the sexual activity
- [00:42:16.760]that happened during that
ambulatory phase. Excuse me.
- [00:42:22.800]So this fits this this fits really nicely
with our original hypothesis
- [00:42:27.360]that at the times
when women were at peak fertility,
- [00:42:30.080]that the negative effects of information
on sexual reward were really amplified.
- [00:42:35.080]But this analysis was limited by the fact
that it's a really small group of women.
- [00:42:39.040]It's only 30 women.
- [00:42:40.760]So we thought to replicate these findings
in a much larger, more diverse
- [00:42:43.840]group of women and to examine a variety
of different measures of inflammation
- [00:42:47.400]and a variety of different ways
of looking at sexual pleasure and desire.
- [00:42:51.080]So for this next study, we recruited
91 women to come into the lab, and there
- [00:42:55.480]they completed a really comprehensive
battery of sexual functioning measures,
- [00:43:00.360]as well as a comprehensive battery of
measures of their inflammatory response.
- [00:43:05.560]So we also measured their vaginal sexual
- [00:43:07.600]arousal using about vaginal photocopies
mcgruff, which indexes
- [00:43:11.480]these really my new changes in blood flow
in response to a sexual film.
- [00:43:15.520]And they completed samples of saliva
and blood and vaginal fluid.
- [00:43:19.360]But to stay consistent
here, I'm just going to be reporting
- [00:43:22.600]on our findings with your
so drumroll, please.
- [00:43:26.200]We found a whole lot of nothing
- [00:43:30.880]like seriously like
impressively null results,
- [00:43:34.000]and this was true if we looked
at different measures of desire.
- [00:43:37.720]So here I'm just showing off our results
with our clinical index of desire,
- [00:43:42.200]which comes from a really well
validated clinical screener.
- [00:43:45.080]But that was also true
if we looked at self-reported desire
- [00:43:48.040]to the sexual film
or their desire that week.
- [00:43:51.720]This was true. If we looked at zero p
or we looked at other
- [00:43:54.440]measures of inflammation
like different kinds of cytokines.
- [00:43:58.480]It was like really impressively null.
- [00:44:00.600]And then we were talking about this
with a group of researchers from Canada
- [00:44:04.640]who had done a similar set of studies
and we were like, we found all results.
- [00:44:08.120]What did you find? And they said,
Good question. Let's go look.
- [00:44:10.720]And these sliced
and diced their data 8 million ways.
- [00:44:12.720]And they also found no results.
- [00:44:15.280]So at least we were confident
in the null myths of these results.
- [00:44:21.120]Now, given the fact
that this wasn't in lab study,
- [00:44:25.480]it would be tremendously difficult
- [00:44:27.240]to try to capture people
during their ovulatory phase.
- [00:44:30.040]It's a really narrow window of time.
- [00:44:32.320]And so we were not actually in this study.
- [00:44:34.440]We were not looking at people
just within that narrow ovulation window.
- [00:44:39.160]And so taken together, the results
from our first study and the results
- [00:44:42.880]from this impressively male study,
what it suggests is that if there is an
- [00:44:46.840]effect of inflammation on sexual desire,
then it's really specific
- [00:44:51.840]to the cycle phase,
really specific to that ambulatory phase.
- [00:44:56.760]But where we did
see some significant effects
- [00:44:59.400]of inflammation in this healthy
sample is in sexual arousal
- [00:45:03.880]and in particular with vaginal blood flow
in response to sexual arousal.
- [00:45:07.880]So our measure of national arousal
is derived from the national photo.
- [00:45:11.200]Put this in a graph
I mentioned a moment ago.
- [00:45:13.040]So here's a picture of the photo
Put this in a graph.
- [00:45:15.240]It's a small, tampon shaped device
- [00:45:18.360]insert themselves into their vagina
in the privacy of a locked room,
- [00:45:22.680]and it measures these really tiny minute
changes in vaginal blood flow.
- [00:45:26.640]The science writer Mary Roach
once called this Cinderella's tampon,
- [00:45:30.000]which I will treasure forever.
- [00:45:32.960]So here I'm presenting on the
- [00:45:34.320]degree of change
in the amount of blood flow.
- [00:45:38.120]But it's our findings
are pretty similar here.
- [00:45:40.080]If we look at how quickly
the arousal response happened
- [00:45:43.240]or how long women spent
- [00:45:45.080]in their highest phase of arousal,
that is the plateau phase.
- [00:45:49.040]So following some of our prior work
- [00:45:52.120]showing differences between women
who are infrequently versus frequently
- [00:45:55.600]sexually active,
we looked at this interaction
- [00:45:57.400]between degree of sexual activity
and the effects of inflammation.
- [00:46:02.120]So women who were regularly
sexually active two or more times a week
- [00:46:06.800]showed a really significant negative
association between inflammation levels
- [00:46:11.040]and the degree to which
- [00:46:12.160]their vaginal blood flow
increased in response to the sexual act.
- [00:46:15.200]So nicely fitting
in with our original theory.
- [00:46:18.600]Surprisingly, we saw actually the opposite
- [00:46:21.040]response in women who were more
infrequently sexually active.
- [00:46:24.480]Another head scratcher
- [00:46:25.520]We don't have a great
explanation for this,
- [00:46:27.240]but one possibility is that women
who are more infrequently sexually active
- [00:46:31.400]have more variable patterns
of sexual arousal,
- [00:46:34.240]especially when they come into the lab.
- [00:46:36.200]And so that may have kind of changed
the way that we are able
- [00:46:40.000]to detect these effects in the lab.
- [00:46:43.120]So everything that I've been talking
about up until this point has really kind
- [00:46:47.200]of looked at inflammation and immune
response across the whole body, right?
- [00:46:51.200]Systemic levels.
- [00:46:52.640]But we're also really interested
in understanding the local effects
- [00:46:56.360]within the reproductive tract
because the effects of the immune system
- [00:47:00.600]can be very different if you're looking
in the general circulation
- [00:47:04.120]versus if you're looking locally
within a particular tissue bed.
- [00:47:08.320]So here I'm going to do a
- [00:47:11.080]little shout out to my graduate student,
Kristen, who's also here in the front row,
- [00:47:15.320]who is leading the next few set of studies
that I'm going to be talking about here.
- [00:47:19.680]So. In the same study
that I described a moment ago, we also had
- [00:47:22.520]women insert a menstrual cup
into their vagina
- [00:47:25.840]for ten minutes before
and after the sexual film,
- [00:47:29.080]and this collected samples
of their vaginal and cervical fluid.
- [00:47:31.800]So it allows us to be able
to look at the composition
- [00:47:33.920]of the lubrication that their body
produced during sexual arousal.
- [00:47:37.720]And not surprisingly, women had a greater
expression of lubrication post arousal.
- [00:47:43.280]So everything that I present here
takes into account the difference
- [00:47:46.280]in the total sample volume
collected in the concentration
- [00:47:49.360]of these findings are of these samples.
- [00:47:52.880]So I'll also note here that I have shifted
away from talking about inflammation,
- [00:47:57.480]and here I'm looking at immunoglobulin
- [00:48:00.400]A, which is a very important mucosal
- [00:48:04.360]antibody that exists
at the boundary points
- [00:48:08.960]and is our first line of
- [00:48:10.680]defense against diseases that occur
within this mucosal environment.
- [00:48:14.040]So is our first line of defense
against sexually transmitted infections.
- [00:48:18.240]We're really interested in
kind of understanding the dynamics there.
- [00:48:22.520]So we found no difference
- [00:48:24.520]in the antibody production in women
who had relatively low levels
- [00:48:29.480]of vaginal sexual arousal from their pre
to post arousal samples.
- [00:48:34.400]There was really not a big difference.
- [00:48:35.840]There was a slight decrease,
but this was not significant.
- [00:48:39.080]However, among women who had really high
levels of national arousal,
- [00:48:43.320]there was a significant increase
in the production of these vaginal anti
- [00:48:49.000]anti sexually transmitted
- [00:48:52.440]And because these antibodies
are so important to the resistance
- [00:48:55.360]disease, it's possible that this effect
is part of a coordinated response
- [00:49:00.320]of the body to use information
about sexual arousal
- [00:49:05.080]to predict the kinds of infection
- [00:49:07.960]that it might encounter
in the subsequent minutes,
- [00:49:11.640]and to shift immune resources
- [00:49:14.520]towards the kinds of immune resources,
the kinds of antibodies
- [00:49:18.320]that are going to be most important
to reduce the possibility
- [00:49:22.760]of having a transmitted infection
in that context.
- [00:49:27.560]So if that's the case, then
it's another instance in which our body
- [00:49:30.320]is using information about sexual arousal,
about sexual pleasure
- [00:49:34.560]in order to cue the activity
of the immune system.
- [00:49:39.040]This is heads up
- [00:49:39.760]number two that I'm going to talk
about sexual trauma for another moment.
- [00:49:42.800]So again, those of you who are tapping out
come back in about two minutes.
- [00:49:47.640]So we're also really interested
in the ways that sexual trauma,
- [00:49:50.560]particularly childhood sexual abuse,
or KASEI, can influence
- [00:49:54.720]how a woman's immune response
to sexual arousal might play out.
- [00:49:58.800]Sadly, these experiences are incredibly
common, and so a fair number of women
- [00:50:03.600]in our sample reported
having experienced childhood sexual abuse.
- [00:50:07.960]So we saw a significantly increased
concentration in vaginal IGA
- [00:50:13.520]in the post arousal samples among women
who did not have trauma histories.
- [00:50:17.960]Unfortunately, in the women
with the history of childhood sexual
- [00:50:21.160]abuse, the level of vaginal antibodies
- [00:50:26.000]Now you're probably thinking as we were.
- [00:50:28.240]Well, this is surely related to what
- [00:50:29.720]you just showed me
in the previous slide, right?
- [00:50:31.400]Like this has to do with surely the women
who have a history of childhood
- [00:50:35.080]sexual abuse have lower levels of arousal
and that that in turn,
- [00:50:38.760]is explaining this decrease
in their rational antibodies.
- [00:50:42.600]But in this particular sample,
that's actually not the case.
- [00:50:45.520]There was no relationship
between the history
- [00:50:48.880]of childhood sexual assault
and the degree of arousal.
- [00:50:52.520]Some women had low arousal.
- [00:50:53.920]Some women had high
arousal in both groups.
- [00:50:56.880]But the same kind of arousal,
the same level of arousal,
- [00:51:00.320]had very different outcomes,
depending on the history of sexual trauma.
- [00:51:05.080]And this, in turn,
might start to explain why we see such
- [00:51:08.240]dramatically different rates
of sexually transmitted infections
- [00:51:11.840]in survivors of childhood sexual abuse,
even when we account for differences
- [00:51:16.320]in sexual activity
patterns and contraceptive barrier use.
- [00:51:20.320]And again, a little
- [00:51:21.400]shout out to sexuality science here,
because I'll note that the pre
- [00:51:25.240]arousal levels are pretty similar in women
with and without trauma histories.
- [00:51:29.920]And so we would not see this difference
unless we studied women
- [00:51:33.760]in the context of sexual arousal, right?
- [00:51:36.560]And given that sexually transmitted
- [00:51:40.720]that they are transmitted during sex,
it would seem really important for us
- [00:51:45.400]to understand the dynamics of how the body
responds during sex and how that in
- [00:51:49.720]turn, might influence our risk
for sexually transmitted infections.
- [00:51:55.640]So welcome back to
those of you who stepped out
- [00:52:00.280]kind of transitioning again here.
- [00:52:01.800]So our next direction for this
line of work is trying
- [00:52:06.400]to replicate the effects in a larger,
more diverse sample
- [00:52:09.560]and really digging
into the mechanism of these effects.
- [00:52:12.560]So does it change with people
have different kinds of partnerships?
- [00:52:15.240]Does it work in trans people? Does it?
- [00:52:17.520]Do we have the same effect in?
- [00:52:18.880]Queer relationships
and people with multiple partnerships.
- [00:52:21.800]Do we see it in older folks,
do we see it in people
- [00:52:23.680]using different kinds of contraception?
- [00:52:25.200]These are all unanswered questions,
- [00:52:26.640]and we're really excited
to kind of delve into that.
- [00:52:29.520]Another avenue that I'm really excited
to follow up is applying these findings
- [00:52:33.720]to understanding premenstrual dysphoric
mood disorder or key MDT.
- [00:52:38.520]So there's increasing evidence
that inflammation and in particular
- [00:52:42.080]the kind of chronic inflammation
that we see in the modern western world
- [00:52:46.520]is associated with depression
and other mood symptoms
- [00:52:51.480]like fatigue and loss of pleasure,
which we call anhedonia.
- [00:52:55.680]So some folks have suggested
that premenstrual dysphoric mood disorder
- [00:52:59.760]might reflect an increase in inflammation
around the time of menses.
- [00:53:05.920]But one of the things that makes
this hypothesis really difficult to test
- [00:53:10.360]is that there's extraordinary variability
in individual relationships
- [00:53:15.240]to their own menstrual cycle
and individual differences
- [00:53:19.720]in how the mood shifts
over the course of the menstrual cycle.
- [00:53:24.280]So just for example, in one study,
we followed women for six months
- [00:53:28.600]and we had them give us daily reports
of their mood and other
- [00:53:31.680]depressive symptoms
for a total of 2534 daily reports.
- [00:53:37.200]The study was a beast.
- [00:53:39.520]And then we measured
and modeled each person's
- [00:53:42.120]individual level of variability,
as well as cycle effects of variability.
- [00:53:46.760]And this is a picture of the absolute mess
that happens when you do that.
- [00:53:51.800]So individual variation
is absolutely overshadowing
- [00:53:56.000]any of cycle that we can detect
in a sample like this.
- [00:54:00.280]But given what we now know
about how sexual activity may interact
- [00:54:05.280]with how inflammation changes
over the course of the cycle and how
- [00:54:09.080]sexual trauma in turn may further amplify
these effects, it's possible
- [00:54:13.600]that we may be able to better
track mood changes that could lead to MDD
- [00:54:18.640]if we account for sexual activity
and trauma history.
- [00:54:22.120]So we're currently conducting a follow up
study that's measuring
- [00:54:24.680]changes in cytokines and hormones
over the course of the menstrual cycle
- [00:54:28.720]in sexually active and abstinent women and
women with and without a trauma history.
- [00:54:32.240]So stay tuned for more results there.
- [00:54:35.120]A great big shout out to the many people
who make this work possible.
- [00:54:38.880]first and foremost,
a huge shout out to my graduate students
- [00:54:42.600]without whom this work
would simply not be possible.
- [00:54:45.480]So right to left here
we've got Katie and Alison.
- [00:54:48.760]Tom Carper, Jones,
Kirsten Clifton and Sophie Sanchez.
- [00:54:51.520]Thank you guys so much for your work.
- [00:54:53.800]It really would not
be possible without you.
- [00:54:55.440]Also, big thanks to our funders,
without whose generous support.
- [00:54:59.200]Again, this work would not be possible.
- [00:55:01.920]And also a special little shout out
- [00:55:04.200]thanks to the era of Zoom
and the Zoom livestream.
- [00:55:07.320]My parents are listening
from the East Coast,
- [00:55:12.040]so mom and dad, big shout out to you.
- [00:55:14.680]Thank you for supporting me
over the years, even when my crazy
- [00:55:18.600]interests led to some pretty awkward
- [00:55:22.920]You've always been my biggest supporters,
and I can't tell you how much
- [00:55:25.920]that's meant to me over the years.
- [00:55:27.840]So thank you all for your attention
and I welcome any questions.
- [00:55:37.840]Thank you so much to learn so much.
- [00:55:40.440]It's wonderful if you have any questions
- [00:55:44.040]and you were here in person,
you're welcome to step up to the mikes.
- [00:55:47.680]If you are via Zoom,
you can put them in the chat.
- [00:55:51.640]We do have one question. We have Zoom.
- [00:55:55.960]There's a question about quantifying.
- [00:56:00.360]Active and sexually active,
so how active is sexually active?
- [00:56:05.400]This is such a great question
and I think really gets to the heart of
- [00:56:09.680]the need for replication of these findings
and really diving
- [00:56:12.600]into the mechanisms of the effect
because sexual activity
- [00:56:17.040]has an enormous range
of diversity of expression, right?
- [00:56:20.920]And it's very difficult for us
to even start to define what is sex like,
- [00:56:26.880]what counts of sexual activity
because of that immense diversity.
- [00:56:31.000]And so one of the things
that we really need to be doing
- [00:56:33.920]moving forward with
- [00:56:34.640]this work is kind of opening up
and kind of looking at our right.
- [00:56:37.680]Do we see this effect in queer folks?
- [00:56:39.960]Do we see this in folks who are
- [00:56:43.360]engaging in sex but
with different kinds of contraception?
- [00:56:47.320]Because that will help us
to sort of tease apart
- [00:56:49.680]what are the specific pieces of this
that really that really matter?
- [00:56:53.840]one of the things that we've
sort of taken away from this,
- [00:56:56.040]not from from the work that we've done,
but from some other researchers
- [00:56:59.680]who have looked at
- [00:57:01.720]women who are in lesbian
relationships versus women
- [00:57:04.600]who are in hetero
relationships versus abstinent women
- [00:57:07.880]is that we do see very similar effects
- [00:57:10.400]among queer and hetero folks,
which suggests the possibility
- [00:57:16.080]that it has to do more
with some of the partnered aspects of sex
- [00:57:20.560]or potentially the sexual
arousal aspects of sex than it does
- [00:57:24.960]the the pure kind
of penetrative components.
- [00:57:28.800]That said, queer women
also engage in penetrative sex.
- [00:57:31.520]That's not necessarily the case, and also
- [00:57:33.720]we tend to see some of these effects
in arousal to masturbation.
- [00:57:37.720]So again, the broad answer
to that question is, I don't know, and I'm
- [00:57:41.480]excited to find out.
- [00:57:53.120]I had a question about when your side
that was talking about low grade
- [00:57:57.000]chronic inflammation
and how that relates to
- [00:58:00.760]like lower vaginal arousal women
who are sexually active.
- [00:58:03.280]What is that inflammation
that you're measuring and like?
- [00:58:06.880]Like how does that how does that
inflammation like present in the body?
- [00:58:10.200]Great question. So there's a lot
- [00:58:11.480]of different ways
that you can measure inflammation.
- [00:58:13.200]It's a it's a whole system.
- [00:58:15.480]one of the ones that we typically measure
is this protein called
- [00:58:18.840]C-reactive protein, which is a it's
a hepatic protein that is made on demand
- [00:58:25.280]in response to a whole lot of different
inflammatory systems across the body.
- [00:58:29.480]So that is reflected
in the general circulation.
- [00:58:33.960]And then we can measure that either
in the blood or in saliva.
- [00:58:36.800]It's just a little bit easier
to get in saliva because then
- [00:58:38.600]we don't have to take blood from people
and that can be a little stressful.
- [00:58:42.360]But there's also different ways
that we can look at
- [00:58:45.520]the way that the immune system
actually communicates with itself
- [00:58:48.800]using particular
signaling molecules called cytokines.
- [00:58:51.960]And so one of the things
that we're really interested in
- [00:58:53.520]is understanding not just the byproducts
of the inflammatory system, but
- [00:58:58.080]also the signals that it sends to itself
and also to other systems.
- [00:59:02.960]There's also kind of functional ways
that you can look at inflammation
- [00:59:06.240]so you can look at things
like wound healing
- [00:59:09.040]or the ways that the inflammatory system
actually changes the tissue.
- [00:59:13.120]So things like actually causing
- [00:59:15.920]changes in the vascular dynamics
that's usually a little bit more of a
- [00:59:19.960]kind of fine grained than what we get to
in this research, just simply because
- [00:59:24.960]we try to be as minimally invasive
as possible with our work
- [00:59:29.440]because we kind of recognize it's already
asking a lot of the people to come
- [00:59:32.280]into the lab and share their most intimate
parts of themselves with us.
- [00:59:36.240]But I think if we were to move forward,
kind of that would be the next step
- [00:59:39.480]of looking at some of those
- [00:59:41.280]because that's your question. Awesome.
- [00:59:55.160]A great talk, thanks, Kim.
- [00:59:57.520]Follow up on that
just a little bit, so a lot.
- [00:59:59.800]I mean, I guess I'm
still trying to process how much the
- [01:00:03.240]level of information
reflected by the C-reactive protein,
- [01:00:06.040]a sort of cause or
which running in parallel.
- [01:00:09.320]But we take we take lots of
anti-inflammatories on a regular basis.
- [01:00:15.000]Does that come in here?
- [01:00:16.480]Is it does that influence your studies
and does that influence
- [01:00:20.040]how people feel arousal
and when people have taken the toxin
- [01:00:23.720]or ibuprofen or something like that
that are really over-the-counter,
- [01:00:28.000]pretty powerful, any
- [01:00:28.720]inflammatory statement for the hundreds
of milligram amounts? Yeah.
- [01:00:31.960]So when we conduct these studies,
we generally exclude people who are taking
- [01:00:37.320]anti-inflammatory medications
on a regular basis,
- [01:00:40.920]and we ask people to avoid
using those kinds
- [01:00:43.960]of over-the-counter medications
on the day that they come in.
- [01:00:47.160]Essentially cause we want kind
of a blank slate in that reflect.
- [01:00:50.560]But I will say that is
an active interest of mine
- [01:00:54.160]because as I mentioned, some of the things
that we're looking at in terms of
- [01:00:58.480]understanding the interactions
- [01:01:01.080]and mood, particularly around this
premenstrual dysphoric disorder.
- [01:01:04.720]one of the implications of the findings
of that study know, assuming that
- [01:01:08.280]we find what we think we're going to find
is that some of the prophylactic effect
- [01:01:13.840]that people experience
by taking these NSAIDs
- [01:01:18.160]in that premenstrual phase
could potentially extend beyond just
- [01:01:23.320]regulating pain or regulating cramps, but
- [01:01:26.640]potentially could
also have an effect on mood as well.
- [01:01:30.480]And if that's the case,
that would be an immensely powerful tool
- [01:01:33.600]for us to have as clinicians. OK, thanks.
- [01:01:46.040]During lockdown,
- [01:01:49.920]first, Tierney, thank you so much
for a very thoughtful,
- [01:01:53.800]interesting and inclusive talk,
I really appreciated that tons.
- [01:01:58.560]I'm going to ask you a question
about the data you didn't
- [01:02:00.680]talk about in your slide
because it was just really interesting.
- [01:02:03.720]I started scratching down notes
because I was going to forget otherwise.
- [01:02:06.920]So when you were showing the slide
- [01:02:10.040]of the Bolivian women
and the CERP measures,
- [01:02:14.600]you replicated your effect,
but you had another variable in there.
- [01:02:17.280]You didn't talk about
which was the poorer or better off.
- [01:02:21.560]Yeah. Would you be willing
to talk a little bit about that
- [01:02:23.840]because you replicated
the pattern in both?
- [01:02:25.880]But just to remind people
or no relationship was higher
- [01:02:29.680]in both cases or the better off? Hmm.
- [01:02:33.200]Yeah. And I I would love
to unpack that further.
- [01:02:36.120]So that piece of the project
- [01:02:39.680]came out of trying to start
to get at some of these mechanisms.
- [01:02:44.080]And one of the things
- [01:02:46.720]that I have a hunch about
- [01:02:50.600]is that part of this effect of the way
that sexual activity
- [01:02:55.480]is having an effect on inflammation
is through the stress system
- [01:03:00.440]because of some of the things
that we found around
- [01:03:02.560]how sexual arousal kind of causes
that decoupling with the stress
- [01:03:06.280]response system,
in particular with cortisol.
- [01:03:09.440]So one of the things we were interested
in, we had some women in that study
- [01:03:14.080]who were really living under extreme
- [01:03:18.000]conditions, extreme financial hardship.
- [01:03:21.280]They were physically
just moving their bodies all day,
- [01:03:25.040]going through really difficult arm work,
know low resource availability.
- [01:03:31.520]And then some of the women lived
kind of a little bit closer to town.
- [01:03:35.240]They had a little bit more eat.
- [01:03:36.600]They just had lighter,
less stress overall.
- [01:03:39.080]And so we were really interested
in understanding the interaction between
- [01:03:42.320]chronic stress that comes
from socioeconomic status
- [01:03:47.400]and its relationship to
these kind of broader system of effects.
- [01:03:51.800]Because we would expect that
if it is really about stress,
- [01:03:56.600]then we would see that
amplified in the folks
- [01:03:59.600]who are experiencing
more chronic daily stressors.
- [01:04:03.400]But what was kind of interesting
is that we did see an ordinal effect
- [01:04:08.120]like an intercept shift, but we didn't
necessarily see the the interaction
- [01:04:11.680]of the shape of the effects,
the way that we had anticipated.
- [01:04:23.800]I don't see any other questions,
- [01:04:26.440]let's call it quickly.
- [01:04:32.720]Thank you so much again,
- [01:04:33.800]and I hope you all will
join us on March 29th, which when
- [01:04:37.600]all our speakers come back together
and have a panel discussion.
- [01:04:42.840]And thank you again to Dr. Lorenz.
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