Chapitre 1
Sex Research: Where Science Meets Taboo
Ever wondered what happens when researchers try to study the most intimate aspects of human life? Mary Roach's "Bonk" takes readers on an unforgettable journey through the peculiar world of sex research, where scientists face raised eyebrows, funding difficulties, and constant misunderstandings. This isn't just another clinical examination of human sexuality-it's a witty, compassionate exploration of how science has struggled to understand what happens in our bodies and minds during intimate moments. The book has developed something of a cult following among science readers, with figures like Neil deGrasse Tyson and Bill Nye praising Roach's ability to make complex science both accessible and entertaining. Despite its sometimes eyebrow-raising content, "Bonk" has become required reading in many human sexuality courses, proving that serious science can coexist with genuine humor when examining even the most sensitive subjects.
Chapitre 2
The Pioneers Who Risked Everything
The early pioneers of sex research faced enormous obstacles that went far beyond scientific challenges. Before the 1970s, studying sexual physiology could destroy a researcher's career, with many facing expulsion from medical associations or even landing on FBI watchlists. Religious intolerance and professional prejudice meant that even studying vaginal secretions invited suspicion of perverse interests.
William Masters and Virginia Johnson emerged as the most significant figures in bringing scientific rigor to the field. Their approach was revolutionary-connecting subjects to machines measuring heart rate and blood pressure, making it impossible to fake responses. This gave their work credibility that previous studies lacked. Their landmark 1966 book "Human Sexual Response" initially received hate mail requiring extra secretaries but eventually became a bestseller, despite being written in dense scientific language that referred to couples as "reacting units" and orgasms as "orgasmic phase expression."
Their observations revealed groundbreaking insights about female anatomy that had been previously misunderstood or ignored. They discovered that outer labia thin and flatten during arousal to facilitate penetration, while inner labia enlarge dramatically and change color. Perhaps most surprisingly, they noted that the clitoris actually retracts under its foreskin just before orgasm, becoming too sensitive for direct stimulation-a finding that contradicted previous assumptions about female pleasure.
For men, they documented phenomena like "postejaculatory glans sensitivity," explaining why continued thrusting after ejaculation can be uncomfortable. Throughout their work, Masters and Johnson emphasized the importance of communication between partners, which informed their later sex therapy practice.
What's particularly striking about these pioneers is how they balanced scientific objectivity with genuine compassion. They weren't just collecting data-they were helping people understand their bodies and improve their relationships. Their work transformed countless bedrooms from places of confusion and frustration to spaces of mutual understanding and satisfaction. Isn't that ultimately what science should do-improve our lives in meaningful ways?
Chapitre 3
The Penis-Camera and Other Ingenious Tools
Masters and Johnson's most extraordinary research tool was their "artificial coition machine"-essentially a mechanical penis-camera that could film female sexual response from the inside. This device allowed them to document hundreds of complete sexual response cycles and make discoveries like the true source of vaginal lubrication (plasma seeping through capillary walls rather than glandular secretions).
What's remarkable about their penis-camera experiments was that women achieved orgasm from the straight-on, mechanical thrusting of a plastic phallus-surprising given that roughly 70% of women report needing additional clitoral stimulation beyond intercourse to reach orgasm. This mystery was later explained by feminist Leonore Tiefer, who noted that their female subjects were pre-screened to be "easily orgasmic" with "positive history of coital orgasmic experience"-hardly representative of average women.
The quest to understand sexual mechanics continues today with high-tech imaging. In Dr. Deng's exam room in Taiwan, couples attempt intercourse while ultrasound wands capture internal images-an experience that feels entirely divorced from genuine intimacy. As one research subject described it, her partner maintained "an idle, disaffected rhythm" while casually chatting with the doctor about their children. The surreal conversation culminated with the doctor transitioning seamlessly from discussing his toddler to instructing, "You can ejaculate now."
Beyond direct imaging, researchers have employed creative methods to study sexual mechanics. A 2003 SUNY Albany team investigated "The Human Penis as a Semen Displacement Device," theorizing that the penis's ridged glans evolved to scoop out competitors' semen. Using artificial vaginas, simulated semen (a precise cornstarch-water mixture), and various phallus models, they demonstrated that ridged penises displaced 91% of "competitor" semen compared to just 35% removal by unridged controls.
Despite the scientific value of such imaging and experiments, there's a recognition that what happens in research settings barely resembles actual sex. Sex transcends its mechanical components-it's "far more than the sum of its moving parts." Yet when those parts malfunction, as they do for millions of people with sexual dysfunction, understanding the mechanics suddenly matters tremendously.
Imagine trying to study something as complex and personal as sexual response while maintaining scientific objectivity. How do you separate the physical from the psychological? The mechanical from the emotional? These researchers developed ingenious-if sometimes bizarre-methods to peer into one of humanity's most private experiences.
Chapitre 4
The Anatomical Truth About Female Pleasure
Princess Marie Bonaparte's groundbreaking research in the 1920s found that women with clitorises more than an inch from their vaginas (teleclitoridiennes) rarely achieved orgasm during intercourse, while those with closer anatomical arrangements (paraclitoridiennes) did so reliably. Kim Wallen of Emory University later verified Bonaparte's findings statistically, developing his "rule of thumb"-if the distance between clitoris and urethra is less than a thumb-width, orgasm during intercourse is likely.
Bonaparte, unwilling to accept her anatomical fate, underwent two surgeries to relocate her clitoris closer to her vagina. The "Halban-Narjani operation" (named after her surgeon and her pseudonym) involved cutting suspensory ligaments to move the organ lower, but failed to improve her situation despite reportedly helping other patients.
Roy Levin proposed another theory about intercourse orgasms, suggesting the periurethral glans (tissue surrounding the urethra) might play a key role. He observed through pornographic videos that this tissue gets partially pulled into the vagina during intercourse and hypothesized women with greater sensitivity there might experience orgasms more easily.
The backlash against Alfred Kinsey's research in the 1950s turned the vaginal orgasm into the "hallmark of well-adjusted femininity" in conservative America. Marriage manuals were stripped of clitoral references, and doctors used premarital exams to prepare women for supposedly fulfilling intercourse without mentioning clitoral stimulation. Some physicians even recommended stretching or snipping hymens with "well-lubricated Pyrex centrifuge tubes" to ease penetration anxiety.
Despite this, researchers like Zwi Hoch and Ernst Grafenberg continued studying vaginal erogenous zones, with Grafenberg identifying what would later be called the G-spot on the front vaginal wall. Both suggested certain positions might better stimulate this area.
Kinsey maintained the most sensible perspective: a woman's level of engagement matters most. Women who regularly experience orgasm during intercourse typically control their own movements rather than depending on their partner's thrusting. As Kim Wallen's recent research confirms, "it's the women's own movement that matters most," though he admits, "women are too complicated."
What's fascinating is how long it took science to acknowledge what many women already knew-that female pleasure is complex and varies significantly between individuals. Why did it take so long for researchers to listen to women's actual experiences rather than imposing preconceived notions about how female sexuality "should" work?
Chapitre 5
The Upsuck Theory: Does Female Orgasm Aid Conception?
The question of whether female orgasm serves a reproductive purpose has fascinated scientists for centuries. In the 19th century, physician Joseph Beck studied a woman with a prolapsed uterus whose cervix was visible at her vaginal opening. During her orgasm, he observed the cervix opening "to the extent of fully an inch" and making "five or six successive gasps," leading him to conclude this created an "upsuck" effect that might help draw sperm toward the egg.
Modern gynecologists remain skeptical. Dr. Mindy Goldman notes the cervix is relatively insensitive to touch, with 95% of women unable to feel cervical contact in Kinsey's studies. Masters and Johnson were upsuck skeptics, documenting that uterine contractions during orgasm are "expulsive, not sucking" in character. Their studies with menstruating women showed fluid being expelled during orgasm, not drawn inward.
Though critics note uterine contractions can reverse direction during ovulation, Masters and Johnson's follow-up study using radiopaque fluid found no evidence of cervical suction during orgasm. Modern fertility experts like Dr. Bob Nachtigall acknowledge the question remains unanswered, noting the difficulty of conducting proper studies on whether female orgasm improves conception rates.
The evidence for female orgasm in animals continues with observations of monkeys mounting other females, showing dramatic uterine contractions during their "ejaculation face." Alfred Kinsey reported similar behavior in cows that would give "a sudden lunge at the peak of response" before dropping into inactivity.
For couples dealing with infertility, such questions become particularly sensitive as sex becomes "work" rather than pleasure. The pressure to perform sexually for reproductive purposes can transform an intimate act into a clinical procedure, adding emotional strain to an already difficult situation.
What makes this question so compelling is how it bridges evolutionary biology and intimate experience. If female orgasm doesn't serve a reproductive purpose, why did it evolve? And if it does aid conception, what does that tell us about the complex interplay between pleasure and reproduction? These questions touch on both scientific curiosity and our understanding of human sexuality's fundamental purpose.
Chapitre 6
The Medical History of Impotence: From Witchcraft to Viagra
The medicalization of impotence began shifting from psychology to urology around 1980, culminating with Viagra's 1998 launch. Pfizer's brilliant marketing rebranded "impotence" as "erectile dysfunction"-a plumbing problem rather than a psychological one. Though psychological factors remain significant in many cases (detectable through nocturnal erection monitoring), urologists now typically start with PDE5 inhibitors like Viagra even for likely psychological cases, using them as a "bridge" while recommending therapy.
Medieval approaches to impotence blamed witchcraft and demons, with the 1491 Malleus Maleficarum describing witches who could make penises disappear or collect them in birds' nests. By the late 1700s, blame shifted to masturbation, with Samuel Tissot's Onanism claiming self-pleasure depleted vital energy and caused impotence, blindness, insanity, and numerous other ailments.
This spawned bizarre anti-masturbation devices including the Penile Pricking Ring-a metal band with spikes that would dig into flesh during nocturnal erections. More elaborate versions included alarms, electric shocks, and painful hair-pulling mechanisms. Parents were advised to tie children's hands to headboards, while physicians like William Robinson even applied red-hot wires to children's genitals as treatment.
The anti-masturbation hysteria reached absurd levels, with doctors like Crommelinck advising men to "urinate quickly, do not shake your penis" to avoid arousal. Treatments included urethral syringes and cauterization. Ironically, regular ejaculation serves a biological function-sperm left too long develop abnormalities (missing or shriveled heads), making them less effective at fertilization.
Sixteenth and seventeenth-century France saw the rise of "impotence trials" where men accused of being unable to perform faced humiliating public examinations. When marriage became a sacrament, impotence was elevated to a crime, and women could seek divorce on these grounds. The accused had to prove his erectile capacity before a team of up to fifteen physicians and legal officials who would examine him in his bedroom. Some defendants resorted to theater performances or manual manipulation to appear erect.
How striking that we've moved from blaming demons and self-pleasure to understanding the vascular mechanics of erection in just a few centuries. Yet despite our scientific progress, many men still feel shame about erectile difficulties, suggesting our cultural attitudes haven't fully caught up with our medical understanding. Isn't it time we approached sexual function with the same matter-of-fact attitude we bring to other health issues?
Chapitre 7
The Testicle Transplant Craze
The quest for virility through testicular enhancement began with Kamil Pasha, an 82-year-old Ottoman vizier with 64 wives, who drank testicle broth made from young animals. His harem obstetrician, Skevos Zervos, observed the feminizing effects of castration in eunuchs and developed a theory that testes were key to lifelong virility. By 1909, Zervos was grafting testicle tissue from young animals onto aging ones, publishing his findings in "Curious Experiences with the Genital Organs of the Male."
By 1916, testicle grafting had gone mainstream with G. Frank Lydston, a Chicago surgeon, publishing in JAMA about implanting a third human testicle into men's scrotums. Beyond claiming improved sexual function, Lydston asserted these grafts cured high blood pressure, senility, arteriosclerosis, and even a young man's habit of writing "incoherent, rambling dissertations on architecture." Initially focusing on men with underdeveloped testicles "the size of a navy bean," Lydston eventually operated on men with normal anatomy and even himself.
French surgeon Serge Voronoff demanded even fresher tissue, advocating for special hospitals where recipients would await organs from "fatally injured cases." Unable to secure human donors, Voronoff turned to chimpanzees and baboons, charging wealthy men enormous sums for slices of ape testicle. Despite dramatic before-and-after photos showing elderly men leaping across lawns, patient testimonials revealed disappointing results: "The genital coldness has changed very little" and "I am increasingly wretched."
San Quentin prison physician Leo Stanley conducted the most extensive experiments, performing 1,000 testicular grafts using tissue from 20 executed inmates and various animals including goats, rams, boars, and deer. He reported miraculous results in asthma, diabetes, epilepsy, sexual function, vision, and even acne. However, as historian David Hamilton noted, prisoners received early parole or cash for participating, likely motivating them to report positive outcomes.
By the 1920s, testicle madness had reached its peak. Bars served "Monkey Gland" cocktails, and Parisian shops sold ashtrays depicting chimps protecting their genitals from Voronoff. Quack doctor John R. Brinkley used his radio station KFKB to promote his four-part goat gland operation, slaughtering forty Toggenburg goats weekly and encouraging patients to select their own donor animal.
What drives otherwise rational people to embrace such bizarre treatments? The testicle transplant craze reveals how vulnerability around sexual performance and aging can override scientific skepticism. Even today, aren't we still susceptible to miracle cures and enhancement products that promise to restore youth and virility? The specifics may change, but the underlying anxieties remain remarkably consistent across generations.
Chapitre 8
The Lady's Boner: Female Arousal Mechanics
Is the clitoris simply a tiny penis? In many ways, yes. The clitoris and penis share remarkable anatomical similarities. Both begin from the same fetal tissue, with the male version expanding while the female remains relatively unchanged. Both organs have a glans, shaft, corpora cavernosa (expandable chambers), and prepuce (foreskin). The clitoris even experiences erections, though less dramatically than the penis.
Ken Maravilla, a University of Washington radiology professor, uses MRI to study female sexual arousal by measuring clitoral blood volume during exposure to erotic videos. His research shows that women's clitorises hold twice as much blood when aroused compared to baseline. While the visible portion (glans) may not noticeably enlarge during arousal, MRI studies reveal that the entire organ-including its hidden portions-routinely doubles in size when aroused.
This led some researchers, particularly urologists, to theorize that women's arousal problems might be blood-flow issues similar to erectile dysfunction in men. Following this logic, pharmaceutical company Pfizer conducted extensive research to determine if Viagra could help women with sexual arousal disorders. After studying 3,000 subjects over eight years, they found that while Viagra did increase genital blood flow in women, most didn't notice any subjective improvement. This confirmed that women's arousal depends more heavily on psychological factors than men's.
The disconnect between physical arousal and mental awareness in women creates a perplexing puzzle. Unlike men, who reliably report arousal when physically erect, women often show genital engorgement without feeling aroused-or feel aroused without showing physical signs. This mind-body disconnect has complicated both diagnosis and treatment.
Women's physical arousal patterns differ fundamentally from men's, responding indiscriminately to sexual imagery regardless of who's involved. Meredith Chivers' research shows women become genitally aroused by all sexual scenarios-male, female, gay, straight-while men respond only to scenes matching their orientation. This happens "automatically" and "remarkably fast." Even footage of bonobos mating triggered physical responses in women but not men.
Yet women's subjective experience often contradicts their physical responses. Though their bodies respond equally to different types of pornography, women report stronger arousal to female-centered content. This mind-body disconnect appears in traumatic contexts too-rape victims sometimes experience physical arousal despite feeling fear and revulsion, as reflex arousal can occur without emotional engagement.
Isn't it fascinating that our bodies can respond independently of our conscious desires? This research challenges our assumptions about the relationship between physical and psychological arousal, suggesting that for women especially, the connection is far more complex than we once thought.
Chapitre 9
The Orgasm That Defies Logic: Beyond Physical Sensation
Marcalee Sipski's research into orgasm in people with spinal cord injuries reveals surprising insights about human sexuality. Despite injuries that should theoretically prevent sexual sensation, 40-50% of people with spinal cord injuries can still experience orgasm. Her laboratory-designed like a hotel room with monitoring equipment-allows subjects privacy while researchers track physiological responses.
Sipski discovered that only complete injury to the sacral nerve roots at the base of the spine definitively prevents orgasm. This suggests orgasm functions primarily as a reflex of the autonomic nervous system-the system controlling involuntary bodily functions. While spinal cord injuries primarily block the somatic nervous system (controlling skin sensations and voluntary movement), the autonomic nervous system often remains partially functional through alternative pathways like the vagus nerve.
Her research reveals orgasm as an internal sensation rarely felt exclusively in the genitals. Subjects report feeling orgasm "all over," "from waist down," or even in the head. This autonomic reflex can be triggered in unexpected ways-some patients develop "compensatory erogenous zones" above their injury level where vibration can trigger orgasmic responses.
The research extends beyond spinal injuries to conditions like multiple sclerosis, where lesions affect sexual response. Some people experience non-genital orgasms through thought alone, during epileptic seizures, or even spontaneously. Sipski explains these as triggering the same reflex through different pathways-"impulses traveling down from the brain rather than up from the genitals." This bidirectional nature helps explain why sexual arousal can be either "reflex" (physical) or "psychogenic" (mental), with different spinal injuries affecting each pathway differently.
For centuries, physicians treated "hysteria"-believed to be caused by retained female "seed"-with manual genital massage. Ancient Greek physicians prescribed midwives to "rub the part gently" until "thick and viscid sperm was expelled," mistaking vaginal lubrication for semen. Alternative treatments included inhaling foul odors like stale urine or crushed bedbugs to "repel the uterus" back to its proper position-reflecting the bizarre belief that the womb could move around the body like an animal.
Genital manipulation persisted through the Victorian era into the twentieth century. Rachel P. Maines's book "The Technology of Orgasm" reveals that early vibrators weren't sold to women but to physicians, who found them a godsend for reducing a half-hour "treatment" to minutes. Surprisingly, Maines found no evidence that male physicians enjoyed or even understood they were providing orgasms.
What does this research tell us about the nature of pleasure itself? If orgasm can occur without genital sensation-or even without any physical stimulation at all-perhaps we need to reconsider our understanding of sexuality as primarily a physical experience. Could the mind be the true sexual organ after all?
Chapitre 10
The Secret to Great Sex: Lessons from Masters and Johnson
Masters and Johnson's largely forgotten 1979 book "Homosexuality in Perspective" documented a remarkable five-year study comparing sexual encounters between straight, gay, lesbian, and "ambisexual" couples in laboratory settings. Some participants were long-term couples while others were complete strangers assigned to each other by the researchers. Sessions occurred late nights or weekends for privacy, with couples observed having sex in a 78-degree room, sometimes with background music.
While the researchers found no physiological differences in arousal and orgasm patterns across sexual orientations, they discovered that committed gay and lesbian couples had the most satisfying sexual encounters. These couples "took their time," lingering at each stage of arousal and teasing each other to prolong excitement. Lesbians were almost as aroused by pleasuring their partners as by receiving pleasure themselves, while gay men paid attention to their partners' entire bodies rather than focusing solely on genitals.
Heterosexual couples, by contrast, showed a goal-oriented approach, with men often unaware of their partners' arousal levels and women rarely teasing men to heighten excitement. Masters and Johnson attributed some differences to "gender empathy" (understanding what feels good to someone with the same anatomy), but noted the bigger factor was communication-gay couples spoke more openly about preferences.
Hormones act as invisible puppet strings behind our sexual behaviors, especially in women. Research confirms this: women experience increased sexual desire mid-cycle during ovulation, initiate sex more frequently (unless avoiding pregnancy), and masturbate more often during this fertile period. When hormones diminish after menopause, these cyclical patterns level out.
Female rhesus monkeys demonstrate this hormonal influence dramatically. When not ovulating, they avoid males, but during fertility, they initiate 80% of sexual encounters. Unlike passionate human encounters, monkey sex appears mechanical-"multimount, multi-intromission ejaculation" involving several brief mountings before completion. This furtive style likely evolved to avoid confrontations with rival males.
The Pill disrupts these natural hormonal cycles in women by flattening the peaks and valleys of desire, raising sex-hormone-binding globulin that reduces free testosterone, potentially causing lasting libido reduction even after discontinuation.
The researchers concluded that the best sex wasn't about technique but about losing oneself in mutual pleasure and communication. Isn't that ultimately what we all seek-connection that transcends the mechanical aspects of sex? Perhaps the most valuable lesson from all this research is that truly satisfying intimacy comes not from perfect bodies or techniques, but from genuine presence and attentiveness to our partners.
