NY Times: What Do Women Want?

By DANIEL BERGNER
Published: January 22, 2009
來源：http://www.nytimes.com/2009/01/25/magazine/25desire-t.html?_r=3&hp=&pagewanted=all

Meredith Chivers is a creator of bonobo pornography.She is a 36-year-old psychology professor at Queen’s University in thesmall city of Kingston, Ontario, a highly regarded scientist and amember of the editorial board of the world’s leading journal of sexualresearch, Archives of Sexual Behavior. The bonobo film was part of aseries of related experiments she has carried out over the past severalyears. She found footage of bonobos, a species of ape, as they mated,and then, because the accompanying sounds were dull — “bonobos don’tseem to make much noise in sex,” she told me, “though the females givea kind of pleasure grin and make chirpy sounds” — she dubbed in someanimated chimpanzee hooting and screeching. She showed the short movieto men and women, straight and gay. To the same subjects, she alsoshowed clips of heterosexual sex, male and female homosexual sex, a manmasturbating, a woman masturbating, a chiseled man walking naked on abeach and a well-toned woman doing calisthenics in the nude.

While the subjects watched on a computer screen, Chivers, who favorshigh boots and fashionable rectangular glasses, measured their arousalin two ways, objectively and subjectively. The participants sat in abrown leatherette La-Z-Boy chair in her small lab at the Center forAddiction and Mental Health, a prestigious psychiatric teachinghospital affiliated with the University of Toronto, where Chivers was apostdoctoral fellow and where I first talked with her about herresearch a few years ago. The genitals of the volunteers were connectedto plethysmographs — for the men, an apparatus that fits over the penisand gauges its swelling; for the women, a little plastic probe thatsits in the vagina and, by bouncing light off the vaginal walls,measures genital blood flow. An engorgement of blood spurs alubricating process called vaginal transudation: the seeping ofmoisture through the walls. The participants were also given a keypadso that they could rate how aroused they felt.

The men, on average, responded genitally in what Chivers terms“category specific” ways. Males who identified themselves as straightswelled while gazing at heterosexual or lesbian sex and while watchingthe masturbating and exercising women. They were mostly unmoved whenthe screen displayed only men. Gay males were aroused in the oppositecategorical pattern. Any expectation that the animal sex would speak tosomething primitive within the men seemed to be mistaken; neitherstraights nor gays were stirred by the bonobos. And for the maleparticipants, the subjective ratings on the keypad matched the readingsof the plethysmograph. The men’s minds and genitals were in agreement.

All was different with the women. No matter what their self-proclaimedsexual orientation, they showed, on the whole, strong and swift genitalarousal when the screen offered men with men, women with women andwomen with men. They responded objectively much more to the exercisingwoman than to the strolling man, and their blood flow rose quickly —and markedly, though to a lesser degree than during all the humanscenes except the footage of the ambling, strapping man — as theywatched the apes. And with the women, especially the straight women,mind and genitals seemed scarcely to belong to the same person. Thereadings from the plethysmograph and the keypad weren’t in much accord.During shots of lesbian coupling, heterosexual women reported lessexcitement than their vaginas indicated; watching gay men, theyreported a great deal less; and viewing heterosexual intercourse, theyreported much more. Among the lesbian volunteers, the two readingsconverged when women appeared on the screen. But when the filmsfeatured only men, the lesbians reported less engagement than theplethysmograph recorded. Whether straight or gay, the women claimedalmost no arousal whatsoever while staring at the bonobos.

“I feel like a pioneer at the edge of a giant forest,” Chivers said,describing her ambition to understand the workings of women’s arousaland desire. “There’s a path leading in, but it isn’t much.” She seesherself, she explained, as part of an emerging “critical mass” offemale sexologists starting to make their way into those woods. Theseresearchers and clinicians are consumed by the sexual problem SigmundFreud posed to one of his female disciples almost a century ago: “Thegreat question that has never been answered and which I have not yetbeen able to answer, despite my 30 years of research into the femininesoul, is, What does a woman want?”

Full of scientific exuberance,Chivers has struggled to make sense of her data. She struggled when wefirst spoke in Toronto, and she struggled, unflagging, as we sat lastOctober in her university office in Kingston, a room she keeps spare tohelp her mind stay clear to contemplate the intricacies of the erotic.The cinder-block walls are unadorned except for three photographs shetook of a temple in India featuring carvings of an entwined couple, anorgy and a man copulating with a horse. She has been ponderingsexuality, she recalled, since the age of 5 or 6, when she ruminatedover a particular kiss, one she still remembers vividly, between herparents. And she has been discussing sex without much restraint, shesaid, laughing, at least since the age of 15 or 16, when, for a fewmale classmates who hoped to please their girlfriends, she drew apicture and clarified the location of the clitoris.

In 1996, when she worked as an assistant to a sexologist at the Centerfor Addiction and Mental Health, then called the Clarke Institute ofPsychiatry, she found herself the only woman on a floor of researchersinvestigating male sexual preferences and what are known as paraphilias— erotic desires that fall far outside the norm. She told me that whenshe asked Kurt Freund, a scientist on that floor who had developed atype of penile plethysmograph and who had been studying malehomosexuality and pedophilia since the 1950s, why he never turned hisattention to women, he replied: “How am I to know what it is to be awoman? Who am I to study women, when I am a man?”

Freund’s words helped to focus her investigations, work that has madeher a central figure among the small force of female sexologistsdevoted to comprehending female desire. John Bancroft, a formerdirector of the Kinsey Institute for Research in Sex, Gender andReproduction, traces sexological studies by women at least as far backas 1929, to a survey of the sexual experiences of 2,200 women carriedout by Katharine Bement Davis, a prison reformer who once served as NewYork City’s first female commissioner of corrections. But thediscipline remains male-dominated. In the International Academy of SexResearch, the 35-year-old institution that publishes Archives of SexualBehavior and that can claim, Bancroft said, most of the field’s leadingresearchers among its 300 or so members, women make up just over aquarter of the organization. Yet in recent years, he continued, in thelong wake of the surveys of Alfred Kinsey, the studies of WilliamMasters and Virginia Johnson, the sexual liberation movement and therise of feminism, there has been a surge of scientific attention, paidby women, to illuminating the realm of women’s desire.

It’s important to distinguish, Julia Heiman, the Kinsey Institute’scurrent director, said as she elaborated on Bancroft’s history, betweenbehavior and what underlies it. Kinsey’s data on sexuality, publishedin the late 1940s and early ’50s in his best-selling books “SexualBehavior in the Human Male” and “Sexual Behavior in the Human Female,”didn’t reveal much about the depths of desire; Kinsey started hisscientific career by cataloging species of wasps and may, Heiman wenton, have been suspicious of examining emotion. Masters and Johnson, whofilmed hundreds of subjects having sex in their lab, drew conclusionsin their books of the late ’60s and early ’70s that concentrated onsexual function, not lust. Female desire, and the reasons some womenfeel little in the way of lust, became a focal point for sexologists,Heiman said, in the ’70s, through the writing of Helen Singer Kaplan, asex therapist who used psychoanalytic methods — though sexologistsprefer to etch a line between what they see as their scientificapproach to the subject and the theories of psychoanalysis. Heimanherself, whom Chivers views as one of sexology’s venerableinvestigators, conducted, as a doctoral candidate in the ’70s, some ofthe earliest research using the vaginal plethysmograph. But soon theAIDS epidemic engulfed the attention of the field, putting a priorityon prevention and making desire not an emotion to explore but anelement to be feared, a source of epidemiological disaster.

To account partly for the recent flourishing of research likeChivers’s, Heiman pointed to the arrival of Viagra in the late ’90s.Though aimed at men, the drug, which transformed the treatment ofimpotence, has dispersed a kind of collateral electric current into thearea of women’s sexuality, not only generating an effort — mostlyfutile so far — to find drugs that can foster female desire as reliablyas Viagra and its chemical relatives have facilitated erections, butalso helping, indirectly, to inspire the search for a fullunderstanding of women’s lust. This search may reflect, as well, acultural and scientific trend, a stress on the deterministic role ofbiology, on nature’s dominance over nurture — and, because of this, oninnate differences between the sexes, particularly in the primal domainof sex. “Masters and Johnson saw men and women as extremely similar,”Heiman said. “Now it’s research on differences that gets funded, thatgets published, that the public is interested in.” She wondered aloudwhether the trend will eventually run its course and reverse itself,but these days it may be among the factors that infuse sexology’sinterest in the giant forest.

“No one right now has a unifying theory,” Heiman told me; the interesthas brought scattered sightlines, glimpses from all sorts of angles.One study, for instance, published this month in the journal Evolutionand Human Behavior by the Kinsey Institute psychologist Heather Rupp,uses magnetic resonance imaging to show that, during the hormonalshifts of ovulation, certain brain regions in heterosexual women aremore intensely activated by male faces with especially masculinefeatures. Intriguing glimmers have come not only from femalescientists. Richard Lippa, a psychologist at California StateUniversity, Fullerton, has employed surveys of thousands of subjects todemonstrate over the past few years that while men with high sex drivesreport an even more polarized pattern of attraction than most males (towomen for heterosexuals and to men for homosexuals), in women theopposite is generally true: the higher the drive, the greater theattraction to both sexes, though this may not be so for lesbians.

Investigating the culmination of female desire, Barry Komisaruk, aneuroscientist at Rutgers University, has subjects bring themselves toorgasm while lying with their heads in an fM.R.I. scanner — he aims tochart the activity of the female brain as subjects near and reach fourtypes of climax: orgasms attained by touching the clitoris; bystimulating the anterior wall of the vagina or, more specifically, theG spot; by stimulating the cervix; and by “thinking off,” Komisaruksaid, without any touch at all. While the possibility of a purelycervical orgasm may be in considerable doubt, in 1992 Komisaruk,collaborating with the Rutgers sexologist Beverly Whipple (whoestablished, more or less, the existence of the G spot in the ’80s),carried out one of the most interesting experiments in femalesexuality: by measuring heart rate, perspiration, pupil dilation andpain threshold, they proved that some rare women can think themselvesto climax. And meanwhile, at the Sexual Psychophysiology Laboratory ofthe University of Texas, Austin, the psychologist Cindy Meston and hergraduate students deliver studies with names like “Short- and long-termeffects of ginkgo biloba extract on sexual dysfunction in women” and“The roles of testosterone and alpha-amylase in exercise-induced sexualarousal in women” and “Sex differences in memory for sexually relevantinformation” and — an Internet survey of 3,000 participants — “Whyhumans have sex.”

Heiman questions whether the insights of science, whether they comethrough high-tech pictures of the hypothalamus, through Internetquestionnaires or through intimate interviews, can ever produce anall-encompassing map of terrain as complex as women’s desire. ButChivers, with plenty of self-doubting humor, told me that she hopes oneday to develop a scientifically supported model to explain femalesexual response, though she wrestles, for the moment, with thepreliminary bits of perplexing evidence she has collected — with thequestion, first, of why women are aroused physiologically by such awider range of stimuli than men. Are men simply more inhibited, moreconstrained by the bounds of culture? Chivers has tried to eliminatethis explanation by including male-to-female transsexuals as subjectsin one of her series of experiments (one that showed only human sex).These trans women, both those who were heterosexual and those who werehomosexual, responded genitally and subjectively in categorical ways.They responded like men. This seemed to point to an inborn system ofarousal. Yet it wasn’t hard to argue that cultural lessons had takenpermanent hold within these subjects long before their emergence asfemales could have altered the culture’s influence. “The horriblereality of psychological research,” Chivers said, “is that you can’tpull apart the cultural from the biological.”

Still, she spoke about a recent study by one of her mentors, MichaelBailey, a sexologist at Northwestern University: while fM.R.I. scanswere taken of their brains, gay and straight men were shownpornographic pictures featuring men alone, women alone, men having sexwith men and women with women. In straights, brain regions associatedwith inhibition were not triggered by images of men; in gays, suchregions weren’t activated by pictures of women. Inhibition, in Bailey’sexperiment, didn’t appear to be an explanation for men’s narrowlyfocused desires. Early results from a similar Bailey study with femalesubjects suggest the same absence of suppression. For Chivers, thisbolsters the possibility that the distinctions in her data between menand women — including the divergence in women between objective andsubjective responses, between body and mind — arise from innate factorsrather than forces of culture.

Chivers has scrutinized, in a paper soon to be published in Archives ofSexual Behavior, the split between women’s bodies and minds in 130studies by other scientists demonstrating, in one way or another, thesame enigmatic discord. One manifestation of this split has come inexperimental attempts to use Viagra-like drugs to treat women whocomplain of deficient desire.

By some estimates, 30 percent of women fall into this category, thoughplenty of sexologists argue that pharmaceutical companies have managedto drive up the figures as a way of generating awareness and demand.It’s a demand, in any event, that hasn’t been met. In men who havetrouble getting erect, the genital engorgement aided by Viagra and itsrivals is often all that’s needed. The pills target genitalcapillaries; they don’t aim at the mind. The medications may enhancemale desire somewhat by granting men a feeling of power and control,but they don’t, for the most part, manufacture wanting. And for men,they don’t need to. Desire, it seems, is usually in steady supply. Inwomen, though, the main difficulty appears to be in the mind, not thebody, so the physiological effects of the drugs have proved irrelevant.The pills can promote blood flow and lubrication, but this doesn’t domuch to create a conscious sense of desire.

Chivers isn’t especially interested at this point, she said, inpharmaceutical efforts in her field, though she has done a bit ofconsulting for Boehringer Ingelheim, a German company in the latestages of testing a female-desire drug named Flibanserin. She can’t,contractually, discuss what she describes as her negligible involvementin the development of the drug, and the company isn’t prepared to saymuch about the workings of its chemical, which it says it hopes to haveapproved by the Food and Drug Administration next year. The medicationwas originally meant to treat depression — it singles out the brain’sreceptors for the neurotransmitter serotonin. As with other such drugs,one worry was that it would dull the libido. Yet in early trials, whileit showed little promise for relieving depression, it left female — butnot male — subjects feeling increased lust. In a way that BoehringerIngelheim either doesn’t understand or doesn’t yet want to explain, thechemical, which the company is currently trying out in 5,000 NorthAmerican and European women, may catalyze sources of desire in thefemale brain.

Testosterone, so vital to male libido, appears crucial to females aswell, and in drug trials involving postmenopausal women, testosteronepatches have increased sexual activity. But worries about a possiblyheightened risk of cancer, along with uncertainty about the extent ofthe treatment’s advantages, have been among the reasons that theapproach hasn’t yet been sanctioned by the F.D.A.

Thinking not of the search for chemical aphrodisiacs but of her ownquest for comprehension, Chivers said that she hopes her research andthinking will eventually have some benefit for women’s sexuality. “Iwanted everybody to have great sex,” she told me, recalling one of herreasons for choosing her career, and laughing as she did when sherecounted the lessons she once gave on the position of the clitoris.But mostly it’s the aim of understanding in itself that compels her.For the discord, in women, between the body and the mind, she hasdeliberated over all sorts of explanations, the simplest being anatomy.The penis is external, its reactions more readily perceived andpressing upon consciousness. Women might more likely have grown up, forreasons of both bodily architecture and culture — and here was cultureagain, undercutting clarity — with a dimmer awareness of the eroticmessages of their genitals. Chivers said she has considered, too,research suggesting that men are better able than women to perceiveincreases in heart rate at moments of heightened stress and that menmay rely more on such physiological signals to define their emotionalstates, while women depend more on situational cues. So there arehints, she told me, that the disparity between the objective and thesubjective might exist, for women, in areas other than sex. And thisdisconnection, according to yet another study she mentioned, isaccentuated in women with acutely negative feelings about their ownbodies.

Ultimately, though, Chivers spoke — always with a scientist’s caution,a scientist’s uncertainty and acknowledgment of conjecture — aboutfemale sexuality as divided between two truly separate, if inscrutablyoverlapping, systems, the physiological and the subjective. Lust, inthis formulation, resides in the subjective, the cognitive;physiological arousal reveals little about desire. Otherwise, she said,half joking, “I would have to believe that women want to have sex withbonobos.”

Besides the bonobos, a body of evidence involving rape has influencedher construction of separate systems. She has confronted clinicalresearch reporting not only genital arousal but also the occasionaloccurrence of orgasm during sexual assault. And she has recalled herown experience as a therapist with victims who recounted these physicalresponses. She is familiar, as well, with the preliminary results of alaboratory study showing surges of vaginal blood flow as subjectslisten to descriptions of rape scenes. So, in an attempt to understandarousal in the context of unwanted sex, Chivers, like a handful ofother sexologists, has arrived at an evolutionary hypothesis thatstresses the difference between reflexive sexual readiness and desire.Genital lubrication, she writes in her upcoming paper in Archives ofSexual Behavior, is necessary “to reduce discomfort, and thepossibility of injury, during vaginal penetration. . . . Ancestralwomen who did not show an automatic vaginal response to sexual cues mayhave been more likely to experience injuries during unwanted vaginalpenetration that resulted in illness, infertility or even death, andthus would be less likely to have passed on this trait to theiroffspring.”

Evolution’s legacy, according to this theory, is that women are proneto lubricate, if only protectively, to hints of sex in theirsurroundings. Thinking of her own data, Chivers speculated that bonobocoupling, or perhaps simply the sight of a male ape’s erection,stimulated this reaction because apes bear a resemblance to humans —she joked about including, for comparison, a movie of mating chickensin a future study. And she wondered if the theory explained whyheterosexual women responded genitally more to the exercising womanthan to the ambling man. Possibly, she said, the exposure and tilt ofthe woman’s vulva during her calisthenics was proc­essed as a sexualsignal while the man’s unerect penis registered in the opposite way.

When she peers into the giant forest, Chivers told me, she considersthe possibility that along with what she called a “rudderless” systemof reflexive physiological arousal, women’s system of desire, thecognitive domain of lust, is more receptive than aggressive. “One ofthe things I think about,” she said, “is the dyad formed by men andwomen. Certainly women are very sexual and have the capacity to be evenmore sexual than men, but one possibility is that instead of it being ago-out-there-and-get-it kind of sexuality, it’s more of a reactiveprocess. If you have this dyad, and one part is pumped full oftestosterone, is more interested in risk taking, is probably moreaggressive, you’ve got a very strong motivational force. It wouldn’tmake sense to have another similar force. You need somethingcomplementary. And I’ve often thought that there is something reallypowerful for women’s sexuality about being desired. That receptivityelement. At some point I’d love to do a study that would look at that.”

The study Chivers is working on now tries to re-examine the results ofher earlier research, to investigate, with audiotaped stories ratherthan filmed scenes, the apparent rudderlessness of female arousal. Butit will offer too a glimpse into the role of relationships in femaleeros. Some of the scripts she wrote involve sex with a longtime lover,some with a friend, some with a stranger: “You meet the real estateagent outside the building. . . .” From early glances at her data,Chivers said, she guesses she will find that women are most turned on,subjectively if not objectively, by scenarios of sex with strangers.

Chivers is perpetually devising experiments to perform in the future,and one would test how tightly linked the system of arousal is to themechanisms of desire. She would like to follow the sexual behavior ofwomen in the days after they are exposed to stimuli in her lab. Ifstimuli that cause physiological response — but that do not elicit apositive rating on the keypad — lead to increased erotic fantasies,masturbation or sexual activity with a partner, then she could deduce atight link. Though women may not want, in reality, what such stimulipresent, Chivers could begin to infer that what is judged unappealingdoes, nevertheless, turn women on.

Lisa Diamond, a newly prominentsexologist of Chivers’s generation, looks at women’s erotic drives in adifferent way. An associate professor of psychology and gender studiesat the University of Utah, with short, dark hair that seems to explodeanarchically around her head, Diamond has done much of her researchoutside any lab, has focused a good deal of her attention outside theheterosexual dyad and has drawn conclusions that seem at odds withChivers’s data about sex with strangers.

“In 1997, the actress Anne Heche began a widely publicized romanticrelationship with the openly lesbian comedian Ellen DeGeneres afterhaving had no prior same-sex attractions or relationships. Therelationship with DeGeneres ended after two years, and Heche went on tomarry a man.” So begins Diamond’s book, “Sexual Fluidity: UnderstandingWomen’s Love and Desire,” published by Harvard University Press lastwinter. She continues: “Julie Cypher left a heterosexual marriage forthe musician Melissa Etheridge in 1988. After 12 years together, thepair separated and Cypher — like Heche — has returned to heterosexualrelationships.” She catalogs the shifting sexual directions of severalother somewhat notable women, then asks, “What’s going on?” Among heranswers, based partly on her own research and on her analysis of animalmating and women’s sexuality, is that female desire may be dictated —even more than popular perception would have it — by intimacy, byemotional connection.

Diamond is a tireless researcher. The study that led to her book hasbeen going on for more than 10 years. During that time, she hasfollowed the erotic attractions of nearly 100 young women who, at thestart of her work, identified themselves as either lesbian or bisexualor refused a label. From her analysis of the many shifts they madebetween sexual identities and from their detailed descriptions of theirerotic lives, Diamond argues that for her participants, and quitepossibly for women on the whole, desire is malleable, that it cannot becaptured by asking women to categorize their attractions at any singlepoint, that to do so is to apply a male paradigm of more fixed sexualorientation. Among the women in her group who called themselveslesbian, to take one bit of the evidence she assembles to back herideas, just one-third reported attraction solely to women as herresearch unfolded. And with the other two-thirds, the explanation fortheir periodic attraction to men was not a cultural pressure to conformbut rather a genuine desire.

“Fluidity is not a fluke,” Diamond declared, when I called her, afterwe first met before a guest lecture she gave at Chivers’s university,to ask whether it really made sense to extrapolate from the experiencesof her subjects to women in general. Slightly more than half of herparticipants began her study in the bisexual or unlabeled categories —wasn’t it to be expected that she would find a great deal of sexualflux? She acknowledged this. But she emphasized that the pattern forher group over the years, both in the changing categories they choseand in the stories they told, was toward an increased sense ofmalleability. If female eros found its true expression over the courseof her long research, then flexibility is embedded in the nature offemale desire.

Diamond doesn’t claim that women are without innate sexualorientations. But she sees significance in the fact that many of hersubjects agreed with the statement “I’m the kind of person who becomesphysically attracted to the person rather than their gender.” For herparticipants, for the well-known women she lists at the start of herbook and for women on average, she stresses that desire often emergesso compellingly from emotional closeness that innate orientations canbe overridden. This may not always affect women’s behavior — theoverriding may not frequently impel heterosexual women into lesbianrelationships — but it can redirect erotic attraction. One reason forthis phenomenon, she suggests, may be found in oxytocin, aneurotransmitter unique to mammalian brains. The chemical’s release hasbeen shown, in humans, to facilitate feelings of trust and well-being,and in female prairie voles, a monogamous species of rodent, to connectthe act of sex to the formation of faithful attachments. Judging byexperiments in animals, and by the transmitter’s importance in humanchildbirth and breast feeding, the oxytocin system, which relies onestrogen, is much more extensive in the female brain. For Diamond, allof this helps to explain why, in women, the link between intimacy anddesire is especially potent.

Intimacy isn’t much of anaphrodisiac in the thinking of Marta Meana, a professor of psychologyat the University of Nevada at Las Vegas. Meana, who serves withChivers on the board of Archives of Sexual Behavior, entered the fieldof sexology in the late 1990s and began by working clinically andcarrying out research on dyspareunia — women’s genital pain duringintercourse. She is now formulating an explanatory model of femaledesire that will appear later this year in Annual Review of SexResearch. Before discussing her overarching ideas, though, we wenttogether to a Cirque du Soleil show called “Zumanity,” a performance ofvery soft-core pornography that Meana mentioned to me before my visit.

On the stage of the casino’s theater, a pair of dark-haired,bare-breasted women in G-strings dove backward into a giant glass bowland swam underwater, arching their spines as they slid up the walls.Soon a lithe blonde took over the stage wearing a pleated and extremelyshort schoolgirl’s skirt. She spun numerous Hula-Hoops around herminimal waist and was hoisted by a cable high above the audience, whereshe spread her legs wider than seemed humanly possible. The crowdconsisted of men and women about equally, yet women far outnumbered menonstage, and when at last the show’s platinum-wigged M.C. cried out,“Where’s the beef?” the six-packed, long-haired man who climbed upthrough a trapdoor and started to strip was surrounded by 8 or 10already almost-bare women.

A compact 51-year-old woman in a shirtdress, Meana explained the genderimbalance onstage in a way that complemented Chivers’s thinking. “Thefemale body,” she said, “looks the same whether aroused or not. Themale, without an erection, is announcing a lack of arousal. The femalebody always holds the promise, the suggestion of sex” — a suggestionthat sends a charge through both men and women. And there was anotherway, Meana argued, by which the Cirque du Soleil’s offering of morefemale than male acrobats helped to rivet both genders in the crowd.She, even more than Chivers, emphasized the role of being desired — andof narcissism — in women’s desiring.

The critical part played by being desired, Julia Heiman observed, is anemerging theme in the current study of female sexuality. Three or fourdecades ago, with the sense of sexual independence brought by thebirth-control pill and the women’s liberation movement, she said, thepredominant cultural and sexological assumption was that female lustwas fueled from within, that it didn’t depend on another’s initiation.One reason for the shift in perspective, she speculated, is a depth ofinsight gathered, in recent times, through a booming of qualitativeresearch in sexology, an embrace of analyses built on personal,detailed interviews or on clinical experience, an approach that hasgained attention as a way to counter the field’s infatuation withstatistical surveys and laboratory measurements.

Meana made clear, during our conversations in a casino bar and on theU.N.L.V. campus, that she was speaking in general terms, that, when itcomes to desire, “the variability within genders may be greater thanthe differences between genders,” that lust is infinitely complex andidiosyncratic.

She pronounced, as well, “I consider myself a feminist.” Then sheadded, “But political correctness isn’t sexy at all.” For women, “beingdesired is the orgasm,” Meana said somewhat metaphorically — it is, inher vision, at once the thing craved and the spark of craving. Aboutthe dynamic at “Zumanity” between the audience and the acrobats, Meanasaid the women in the crowd gazed at the women onstage, excitedlyimagining that their bodies were as desperately wanted as those of theperformers.

Meana’s ideas have arisen from both laboratory and qualitativeresearch. With her graduate student Amy Lykins, she published, inArchives of Sexual Behavior last year, a study of visual attention inheterosexual men and women. Wearing goggles that track eye movement,her subjects looked at pictures of heterosexual foreplay. The menstared far more at the females, their faces and bodies, than at themales. The women gazed equally at the two genders, their eyes drawn tothe faces of the men and to the bodies of the women — to the facialexpressions, perhaps, of men in states of wanting, and to the sexualallure embodied in the female figures.

Meana has learned too from her attempts as a clinician to help patientswith dyspareunia. Though she explained that the condition, which canmake intercourse excruciating, is not in itself a disorder of lowdesire, she said that her patients reported reduced genital pain astheir desire increased. The problem was how to augment desire, anddespite prevailing wisdom, the answer, she told me, had “little to dowith building better relationships,” with fostering communicationbetween patients and their partners. She rolled her eyes at suchniceties. She recalled a patient whose lover was thoroughly empatheticand asked frequently during lovemaking, “ ‘Is this O.K.?’ Which wasvery unarousing to her. It was loving, but there was no oomph” — nourgency emanating from the man, no sign that his craving of the patientwas beyond control.

“Female desire,” Meana said, speaking broadly and not only about herdyspareunic patients, “is not governed by the relational factors that,we like to think, rule women’s sexuality as opposed to men’s.” Shefinished a small qualitative study last year consisting of longinterviews with 20 women in marriages that were sexually troubled.Although bad relationships often kill desire, she argued, good onesdon’t guarantee it. She quoted from one participant’s representativeresponse: “We kiss. We hug. I tell him, ‘I don’t know what it is.’ Wehave a great relationship. It’s just that one area” — the area of herbed, the place desolated by her loss of lust.

The generally accepted therapeutic notion that, for women, incubatingintimacy leads to better sex is, Meana told me, often misguided.“Really,” she said, “women’s desire is not relational, it’snarcissistic” — it is dominated by the yearnings of “self-love,” by thewish to be the object of erotic admiration and sexual need. Still onthe subject of narcissism, she talked about research indicating that,in comparison with men, women’s erotic fantasies center less on givingpleasure and more on getting it. “When it comes to desire,” she added,“women may be far less relational than men.”

Like Chivers, Meana thinks of female sexuality as divided into twosystems. But Meana conceives of those systems in a different way thanher colleague. On the one hand, as Meana constructs things, there isthe drive of sheer lust, and on the other the impetus of value. Forevolutionary and cultural reasons, she said, women might set a highvalue on the closeness and longevity of relationships: “But it’s wrongto think that because relationships are what women choose they’re theprimary source of women’s desire.”

Meana spoke about two elements that contribute to her thinking: first,a great deal of data showing that, as measured by the frequency offantasy, masturbation and sexual activity, women have a lower sex drivethan men, and second, research suggesting that within long-termrelationships, women are more likely than men to lose interest in sex.Meana posits that it takes a greater jolt, a more significant stimulus,to switch on a woman’s libido than a man’s. “If I don’t love cake asmuch as you,” she told me, “my cake better be kick-butt to get meexcited to eat it.” And within a committed relationship, the crucialstimulus of being desired decreases considerably, not only because thewoman’s partner loses a degree of interest but also, more important,because the woman feels that her partner is trapped, that a choice —the choosing of her — is no longer being carried out.

A symbolic scene ran through Meana’s talk of female lust: a womanpinned against an alley wall, being ravished. Here, in Meana’s vision,was an emblem of female heat. The ravisher is so overcome by a cravingfocused on this particular woman that he cannot contain himself; hetransgresses societal codes in order to seize her, and she, feelingherself to be the unique object of his desire, is electrified by herown reactive charge and surrenders. Meana apologized for theregressive, anti-feminist sound of the scene.

Yet while Meana minimized the role of relationships in stoking desire,she didn’t dispense with the sexual relevance, for women, of beingcared for and protected. “What women want is a real dilemma,” she said.Earlier, she showed me, as a joke, a photograph of two control panels,one representing the workings of male desire, the second, female, thefirst with only a simple on-off switch, the second with countlessknobs. “Women want to be thrown up against a wall but not trulyendangered. Women want a caveman and caring. If I had to pick an actorwho embodies all the qualities, all the contradictions, it would beDenzel Washington. He communicates that kind of power and that he is agood man.”

After our discussion of the alley encounter, we talked about erotic —as opposed to aversive ­— fantasies of rape. According to an analysisof relevant studies published last year in The Journal of Sex Research,an analysis that defines rape as involving “the use of physical force,threat of force, or incapacitation through, for example, sleep orintoxication, to coerce a woman into sexual activity against her will,”between one-third and more than one-half of women have entertained suchfantasies, often during intercourse, with at least 1 in 10 womenfantasizing about sexual assault at least once per month in apleasurable way.

The appeal is, above all, paradoxical, Meana pointed out: rape meanshaving no control, while fantasy is a domain manipulated by the self.She stressed the vast difference between the pleasures of the imaginedand the terrors of the real. “I hate the term ‘rape fantasies,’ ” shewent on. “They’re really fantasies of submission.” She spoke about thethrill of being wanted so much that the aggressor is willing tooverpower, to take. “But ‘aggression,’ ‘dominance,’ I have to findbetter words. ‘Submission’ isn’t even a good word” — it didn’t reflectthe woman’s imagining of an ultimately willing surrender.

Chivers, too, struggled over language about this subject. The topicarose because I had been drawn into her ceaseless puzzling, as couldeasily happen when we spent time together. I had been thinking aboutthree ideas from our many talks: the power, for women, in beingdesired; the keen excitement stoked by descriptions of sex withstrangers; and her positing of distinct systems of arousal and desire.This last concept seemed to confound a simpler truth, that womenassociate lubrication with being turned on. The idea of dual systemsappeared, possibly, to be the product of an unscientific impulse, awish to make comforting sense of the unsettling evidence of women’sarousal during rape and during depictions of sexual assault in the lab.

As soon as I asked about rape fantasies, Chivers took my pen and wrote“semantics” in the margin of my notes before she said, “The word ‘rape’comes with gargantuan amounts of baggage.” She continued: “I walk afine line, politically and personally, talking frankly about thissubject. I would never, never want to deliver the message to anyonethat they have the right to take away a woman’s autonomy over her body.I hammer home with my students, ‘Arousal is not consent.’ ”

We spoke, then, about the way sexual fantasies strip away the prospectof repercussions, of physical or psychological harm, and allow forunencumbered excitement, about the way they offer, in this sense, apure glimpse into desire, without meaning — especially in the case ofsexual assault — that the actual experiences are wanted.

“It’s the wish to be beyond will, beyond thought,” Chivers said about rape fantasies. “To be all in the midbrain.”

One morning in the fall,Chivers hunched over her laptop in her sparsely decorated office. Shewas sifting through data from her study of genital and subjectiveresponses to audiotaped sex scenes. She peered at a jagged red linethat ran across the computer’s screen, a line that traced one subject’svaginal blood flow, second by second. Before Chivers could use acomputer program to analyze her data, she needed to “clean” it, as theprocess is called — she had to eliminate errant readings, moments whena subject’s shifting in her chair caused a slight pelvic contractionthat might have jarred the plethysmograph, which could generate a spikein the readings and distort the overall results. Meticulously, shescanned the line, with all its tight zigs and zags, searching for spotswhere the inordinate height of a peak and the pattern that surroundedit told her that arousal wasn’t at work, that this particular instantwas irrelevant to her experiment. She highlighted and deleted oneaberrant moment, then continued peering. She would search in this wayfor about two hours in preparing the data of a single subject. “I’mgoing blind,” she said, as she stared at another suspicious crest.

It was painstaking work — and difficult to watch, not only because itmight be destroying Chivers’s eyesight but also because it seemed sodwarfed by the vastness and intricacy of the terrain she hoped tounderstand. Chivers was constantly conjuring studies she wanted tocarry out, but with numberless aberrant spikes to detect and cleanse,how many could she possibly complete in one lifetime? How many could bedone by all the sexologists in the world who focus on female desire,whether they were wiring women with plethysmographs or mapping theactivity of their brains in fM.R.I. scanners or fitting them withgoggles or giving them questionnaires or following their erotic livesfor years? What more could sexologists ever provide than intriguinghints and fragmented insights and contradictory conclusions? Could anyconclusion encompass the erotic drives of even one woman? Didn’t thesexual power of intimacy, so stressed by Diamond, commingle withMeana’s forces of narcissism? Didn’t a longing for erotic tendernesscoexist with a yearning for alley ravishing? Weren’t these but twoexamples of the myriad conflicting elements that create women’s lust?Had Freud’s question gone unanswered for nearly a century not becausescience had taken so long to address it but because it is unanswerable?

Chivers, perhaps precisely because her investigations are incisive andher thinking so relentless, sometimes seemed on the verge ofcontradicting her own provisional conclusions. Talking about how herresearch might help women, she said that it could “shift the way womenperceive their capacity to get turned on,” that as her lab results maketheir way into public consciousness, the noncategorical physiologicalresponses of her subjects might get women to realize that they can beturned on by a wide array of stimuli, that the state of desire is muchmore easily reached than some women might think. She spoke abouthelping women bring their subjective sense of lust into agreement withtheir genital arousal as an approach to aiding those who complain thatdesire eludes them. But didn’t such thinking, I asked, conflict withher theory of the physiological and the subjective as separate systems?She allowed that it might. The giant forest seemed, so often, toocomplex for comprehension.

And sometimes Chivers talked as if the actual forest wasn’t visible atall, as if its complexities were an indication less of inherentintricacy than of societal efforts to regulate female eros, of culturalconstraints that have left women’s lust dampened, distorted,inaccessible to understanding. “So many cultures have quite strictcodes governing female sexuality,” she said. “If that sexuality isrelatively passive, then why so many rules to control it? Why is it sofrightening?” There was the implication, in her words, that she mightnever illuminate her subject because she could not even see it, thatthe data she and her colleagues collect might be deceptive, mightrepresent only the creations of culture, and that her interpretationsmight be leading away from underlying truth. There was the intimationthat, at its core, women’s sexuality might not be passive at all. Therewas the chance that the long history of fear might have buried thenature of women’s lust too deeply to unearth, to view.

It was possible to imagine, then, that a scientist blinded by staringat red lines on her computer screen, or blinded by peering at anyaccumulation of data — a scientist contemplating, in darkness, theparadoxes of female desire — would see just as well.

Daniel Bergner is a contributingwriter for the magazine. His new book, “The Other Side of Desire: FourJourneys Into the Far Realms of Lust and Longing,” will be publishedthis month.