The Stimulating Paradox of Female Desire

The New York Times Magazine recently ran a great piece called “What Do Women Want?” about research delving into the distinctions between male and female desire and arousal, among other areas.  Much of the piece focuses on the work of psychologist Meredith Chivers from Queens University who is doing research measuring arousal in men and women in response to watching images of various sex-participant combinations, and gauging verbalized versus bodily responses to the stimuli. 

The tools of her trade include plethysmographs, an apparatus that fits over the penis to measure swelling and a vaginal probe that measures genital blood flow; and bonobo ape porn.  Sound interesting?  One of her studies, described in the excerpt below, found men to be  predictable: they were aroused by pretty much what they said would arouse them.  Women, on the other hand, were anything but predictable.  From the article:

While the subjects watched on a computer screen, Chivers measured their arousal in two ways, objectively and subjectively. The participants sat in a brown leatherette La-Z-Boy chair in her small lab at the Center for Addiction and Mental Health, a prestigious psychiatric teaching hospital affiliated with the University of Toronto, where Chivers was a postdoctoral fellow and where I first talked with her about her research a few years ago. The genitals of the volunteers were connected to plethysmographs — for the men, an apparatus that fits over the penis and gauges its swelling; for the women, a little plastic probe that sits in the vagina and, by bouncing light off the vaginal walls, measures genital blood flow. An engorgement of blood spurs a lubricating process called vaginal transudation: the seeping of moisture through the walls. The participants were also given a keypad so that they could rate how aroused they felt.

Results for the men…

The men, on average, responded genitally in what Chivers terms “category specific” ways. Males who identified themselves as straight swelled while gazing at heterosexual or lesbian sex and while watching the masturbating and exercising women. They were mostly unmoved when the screen displayed only men. Gay males were aroused in the opposite categorical pattern. Any expectation that the animal sex would speak to something primitive within the men seemed to be mistaken; neither straights nor gays were stirred by the bonobos. And for the male participants, the subjective ratings on the keypad matched the readings of the plethysmograph. The men’s minds and genitals were in agreement.

And for the women…

All was different with the women. No matter what their self-proclaimed sexual orientation, they showed, on the whole, strong and swift genital arousal when the screen offered men with men, women with women and women with men. They responded objectively much more to the exercising woman than to the strolling man, and their blood flow rose quickly — and markedly, though to a lesser degree than during all the human scenes except the footage of the ambling, strapping man — as they watched the apes. And with the women, especially the straight women, mind and genitals seemed scarcely to belong to the same person. The readings from the plethysmograph and the keypad weren’t in much accord. During shots of lesbian coupling, heterosexual women reported less excitement than their vaginas indicated; watching gay men, they reported a great deal less; and viewing heterosexual intercourse, they reported much more. Among the lesbian volunteers, the two readings converged when women appeared on the screen. But when the films featured only men, the lesbians reported less engagement than the plethysmograph recorded. Whether straight or gay, the women claimed almost no arousal whatsoever while staring at the bonobos.

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Talking About the Science of Sex and Love: An Interview with Author Jena Pincott

Here’s a quick pop quiz: who makes more money, hookers on birth control or off?  During difficult economic conditions, are Playboy Playmates generally older or younger, heavier or thinner?  Why are men attracted to larger breasts?  And do gentlemen really prefer blondes?  (I’ll give you the answer to that last one: yes… sort of.) 

These and many more questions are discussed in Jena Pincott’s candid, evidence-based book, Do Gentlemen Really Prefer Blondes?: Bodies, Behavior, and Brains–The Science Behind Sex, Love, and Attraction. If science could ever be considered sexy, this is the book that shows precisely why.  Jena Pincott recently chatted with Neuronarrative about brains in love and lust, the power of dilated pupils, and whether semen has mind control properties, among other topics.

 

Do Gentlemen Really Prefer Blondes? is a book that answers a slew of questions people have on their minds all the time but aren’t really sure how to ask, or where to ask–or even if they can get away with asking.  What inspired you to write this book?

Do Gentlemen Really Prefer Blondes? is a book about how genes, hormones, and instincts affect our love lives in ways we might not even realize.  I’ve always been fascinated by the things that (mostly) slip under the radar of awareness.  Smell is one of them — at one point, when I was single and dating, I wondered why it is that I like the smell of some men but not others.  This led me to do some research on the relationships between body odor preference and genes (more on this below).  While I was looking into this, many other love-sex-and-attraction-related questions surfaced — and I thought the answers would make a fascinating book.

 

The evolutionary dynamics underlying mating behavior have been discussed for quite a while, and always with the controversy we’ve come to expect from any subject involving evolutionary explanations for human behavior.  Has your foray into this topic hot zone brought any controversy your way? 

Yes, many of the topics in the book are grounded in evolutionary psychology — and many evolutionary theories just cannot be proven.  Are breasts, long hair, and symmetrical features sexually selected traits?  Darwin thought they were. How about creativity, intelligence, humor, and dance and musical ability?  There’s an argument there, although it’s likely that other evolutionary pressures also influenced these traits.  To the extent that evolutionary psychology is controversial, so is my book.  Then again, as I’ve recently discovered, a disturbing number of people don’t believe in evolution at all!

 

So let’s get into a few of the areas you cover in the book. You say that “Love changes the brain” and that the brain-in-love even “grows.”  Tell us a little bit about why (and how) this happens. 

I love what Einstein said about this: “How on earth are you ever going to explain in terms of chemistry and physics so important a biological phenomenon as first love?”

Well, there are a number of studies in which subjects in love were asked to lie inside a fMRI machine and gaze at a picture of their beloved.  In brief, here’s what researchers found from the brain scans:  the ventral tegmental area (VTA) is activated; this produces the “feel-good” hormone dopamine, which targets the reward areas of the caudate nucleus and nucleus accumbens. It’s a high, and it’s addictive.  Bonding is aided and abetted by such hormones as oxytocin and vasopressin. The obsessive fixation many of us get when we first fall in love — can’t stop thinking about him or her — is due to low serotonin levels.

Meanwhile, the prefrontal cortex, the part of the brain responsible for reasoning, and the amygdala, related to fear, are deactivated — which explains why a lot of us become reckless fools in love.  If a woman in love remembers more details than men do, it’s because there’s more activity in the female hippocampus, the region associated with memory.  And it seems true that when it comes to love men are more visual than women are — guys show more activity in their visual cortex.  

When two people fall in love, they form a neural pattern of associations and rewards that are strengthened over time and with use.  Researchers call this a “love-related” network, and there’s some evidence that people in close relationships, when reminded of their love, perform better on mental tasks.

 

Are there any specific marks of distinction between the brain-in-love and the brain-in-lust? 

Yes, researchers such as anthropologist Helen Fisher believe that love and lust are separate yet overlapping neural experiences.  That’s why you can love your spouse yet be turned on by a stranger. Love and lust are both highly rewarding and addictive — and affect very similar regions of the brain — but there are some distinct differences. For instance, brain scans of people in loving, long-term relationships show increased activity in the ventral pallidum, a region of the brain rich with oxytocin and vasopressin receptors that meditate pair-bonding and attachment. 

 

On the topic of attraction, you say that symmetry is the name of the game.  You also talk about the eyes as “the face’s most blatant and bewitching feature” – particularly the pupils.  How is it that humans have come to value qualities such as facial symmetry and pupil size so highly when selecting a mate?  (and what is it about eyes? Why not lips, or ears?)

Facial symmetry is a cue of health and developmental stability.  Interestingly, researchers reviewing medical records found that subjects with the most symmetrical features had fewer infections. As for eyes — whether or not they’re windows to the soul, they do reveal more emotional cues than the ears or nose.  (Although the lips are important — eye contact is most effective when paired with a smile).  Dilated pupils signal emotional and sexual arousal, which is why men in particular are attracted to them. 

 

Much research lately has focused on the sense of smell in terms of attraction.  Perfumes, cologne and the ever-elusive human pheromones are in the spotlight.  In a nutshell, what do we know about the role smell plays in attraction?  Can someone scent him or herself into a meaningful relationship?

There’s so much to say about smell and sexuality! I think it’s the section of my book that I like the most.   In brief, we know smell certainly does mediate attraction. Androstadienone, a testosterone derivative in men’s sweat, has been found to make women more attentive and lift their moods.  There’s no universal aphrodisiac:  no cologne, perfume, or spray-on pheromone that will necessarily attract a mate. (But they may boost a person’s confidence, and that helps!)

Women are particularly picky about men’s body odor smells.  It turns out that women prefer the smell of men whose immune system genes  (major histocompatibility complex or MHC) are mostly different from their own.  There’s an evolutionary explanation: children whose parents are genetically dissimilar would inherit a more diverse set of immune system genes.  (This was the topic that inspired the book; see question #1 above,)

 

One of the things in the book I found surprising (I suppose because I’d never heard anyone talk about it before) is that semen is a sort of “feel good” serum, capable of inducing a temporary form of mind control.  What’s the deal with this?

Well, it’s a provocative theory, and it goes as follows:  Semen contains hormones and proteins.  Absorbed through the vaginal walls, these hormones and proteins enter the bloodstream and possibly breach the blood-brain barrier. Whether or not this has any psychological affect on a person is unclear and difficult to prove, although a study has found that women who are regularly exposed to their partner’s semen are less depressed than women who use condoms most of the time (regardless of the strength of the relationship). There’s an evolutionary argument for this: if there’s something in semen that makes women happier, they’ll come back for more. 

 

Now that you’ve answered some of the questions on all of our minds, what’s next on your radar screen?

What can surpass the science of love, sex, and attraction?  I’m always on the lookout for fascinating new research on this topic, which I report on in my blog at www.jenapincott.com.

Credit for photo: Lisa Hancock

The Strange Case of Hypersexuality

I happened to catch part of a Science Channel show called Secret Life of the Brain: Losing Control, which examined the lives of four people who each had experienced a brain injury resulting in severe obsessive disorders.  The extent of the obsession in each case was dramatically life-altering -affecting relationships, careers, and making any sense of homeostasis or normalcy impossible. 

In one case, a woman experienced brain trauma resulting in hypersexuality.  Once a committed, monogamous wife, she became unable to control her libido and desire to sleep with random men.  To paraphrase one of the commentating psychologists on the show, her “braking system to regulate sexual desire and activity was no longer functioning.”  

During her interviews, the woman was obviously distraught but equally unable to do anything about her behavior. She confessed that after a random sexual interlude, she experienced regret and remorse about further damaging her marriage, but eventually she did exactly the same thing over and over again. 

What intrigues me about this, combined with some subsequent research on the topic, is two things: first, the consistency with which hypersexuality presents as a result of (particularly) temporal lobe injuries.  Most of these sexual disorders are not as severe as that of the woman in the Science Channel show, and are often short-lived, but how common they are is surprising to me.   This study details five cases of brain-trauma induced hypersexuality, ranging from marginally embarrassing behavior to outright sexual aggression. Here’s an abbreviated version of one of the cases:

A 24-year-old male was admitted to the hospital in coma due to severe head injury following a road accident.  He had a Glasgow Coma score of 3 at the time of admission. Ocular examination revealed normal sized pupils, both of which reacted sluggishly to light. His limbs were flaccid and all tendon reflexes were depressed. He remained deeply comatose for seven weeks after which his level of consciousness started to improve gradually. By the end of the tenth week, he had recovered sufficiently to the extent where he could obey verbal commands, but remained aphasic until the twelfth week. At this time, he began to manifest hypersexual behaviour. The latter was first signalled by the strong arousal anytime he was being attended to by female ward staff. This was soon replaced by increasing agitation whenever a female was nearby; and subsequently – when his ability to verbalise returned – his unabashed demand for sex, and finally his attempt to grab a female attendant. Besides minor tranquilizer which was given on account of his agitation, no specific medication was administered to control his altered sexual behaviour. He progressively became less agitated in the presence of female staff and by the end of the second week after onset of hypersexual behaviour, he had completely normalized.

The second thing that intrigues me about this topic is how a heightened understanding of this behavior may further understanding of deviant sexual behavior in general. The linkage between brain injury, or otherwise-induced brain disorder (including, perhaps, genetic) and aberrant, obsessive or aggressive sexual behavior may in fact be very strong – which in turn opens a three-story can of worms on the moral front.  I’ll be very interested to see how this plays out. 

For those interested, this literature review covers a great deal of ground on the topic, including advances to date and limitations of brain imaging studies on hypersexuality. And here’s a list of 16 known causes of hypersexuality.

The Science of “What?!?”: Chatting with Author Mary Roach

You know from the first page of a Mary Roach book that you’re not in for a typical walk in the science park. Of course, when you picked up a book with the title Stiff, or Spook, or Bonk you were probably already hoping for something…different. And on that count, and many others, Roach’s books deliver the goods.

In the latest of her off-beat travels in the world of wierd science– Bonk: The Curious Coupling of Science and Sex—Roach is tourguide along the varied paths of sex science history – from the days of Masters and Johnson and Alfred Kinsey to the present day cadre of sex researchers and the fantastically odd challenges they face. The stories we’re told along the way are anything but mundane and each is delivered with refreshing wit (first hand testimony: laughing while reading isn’t optional).  Mary recently chatted with Neuronarrative about her work and writing Bonk.

You write unusually entertaining books about topics most writers wouldn’t think to take on so directly. What’s your thought process leading to a topic like the afterlife, or human cadavers, or the science of sex? 

It’s pretty simple.  Everything I do falls into the general category of peculiar science.  On top of that, it’s got to have some grabby historical elements and some potential for humor.  That eliminates just about everything right there.  This is always the hardest part for me.  The idea. 

 

Many science books are written as arguments to support a thesis, which can make reading them a dry, jargon-laden affair.  Your approach to science is quite obviously different – you’re engaged in a much more personal way.  How did you come to approach science, so often the stuff of axioms and arguments, with such personal engagement? 

This is what happens when people with BA degrees set out to write about science.  The secret to my books? Utter ignorance.  I’m not entirely joking.  The more you know about a topic, the harder it is to skate around as I do.  I think that to a certain extent, my humor depends on my being new to the topic.  A lot of what I write about is research that I stumble onto and that makes me go, “No way!  They did what??!?”   But if I had a background in that particular science, the research would make perfect sense, business as usual.  That wonderful surreal quality would disappear. 

 

So let’s talk about Bonk.  You say that the study of sex goes way, way back – even Leonardo da Vinci dabbled in it a bit.  From Leo to Kinsey to now, how far have we come in understanding what makes our nether regions hum? 

The gynecologist Robert Latou Dickinson, one of the earliest sex researchers – and the man who got Kinsey interested in sex research – mentioned something fairly amazing.  He’d had, I don’t know, six or seven couples come to him complaining that they were having trouble conceiving.  (This was around the turn of the last century.)  Turned out that in all cases, the men had only penetrated the outer labia.  They thought that was intercourse.    It wasn’t just that no one studied sex; no one even talked about it.  So we’ve come a long way, certainly.  That’s not to say that the work is done, though. 

 

Speaking of Kinsey, you say in the book that he was described by some as a “masochist” and a “voyeur” with an unorthodox fondness for swizzle sticks and toothbrushes. Was Kinsey a case of genius paired with perversion, or was he just a guy especially involved with his subjects (be they wasps or…other things)?

I’ve read both biographies of Kinsey – okay, portions of them – and it’s really difficult to say.  One biographer suggested the former, one the latter.   Ultimately, Kinsey did us all such a tremendous service — by shattering the boundaries of what is “normal” sexually — that  I think of him as neither.  Not pervert, not eccentric, obsessive scientist, just flat-out hero.

  

What’s hands down the strangest sex experiment you know of (or were party to)?

That’s a tough one. So many to choose from.  Masters and Johnson undertook a doozy that was designed to disprove the upsuck theory.   This was a theory that the contractions of female orgasm serve to suck the semen up through the cerivx, thus upping the odds of conception.  M&J didn’t buy it.  So they cooked up some ersatz semen (I put the recipe in Bonk), and added a radiopaque dye.  The stuff was loaded into a cervical cap, and then the women, while wearing the capful o’ semen, proceeded to gratify themselves in front of an x-ray machine.  The idea was that if the pretend semen was being sucked up, it would show up on the x-rays.   It didn’t. 

 

You’ve been called “a writer impervious to embarrassment,” and no doubt you’ve earned the title. While working on Bonk, was there anything that turned you a few shades of red (or even came close)? 

The obvious answer would be the 4-D coital ultrasound imaging that I volunteered Ed and myself for.   It actually wasn’t embarrassing; because it honestly didn’t seem like sex.  It felt like some strange, awkward medical procedure that you know will be over in 20 minutes, and you’re just going to get through it.  Mostly I felt guilty for dragging Ed into it.  He was the one with the burden of performance. I was taking notes through it all.  Also, I knew how much fun it was going to be to write up the scene, and that helped mitigate the embarrassment.

 

You say that you’re a writer “obsessed with my research.” So after obsessively taking on a couple of the biggies–death and sex–what’s next?  How do you top two topics that preoccupy most of our minds most of the time?

I’m writing about space exploration — the fabulous, surreal insanity of trying to stay alive in an environment for which we’re utterly unequipped.   Lots of fun aerospace medicine history stuff, bizarre simulated missions here on earth…

 

Link to Mary Roach’s website

Credit for Mary Roach’s photo: David Paul Morris