The Female Brain (13 page)

Women, because they can have only one child every nine months, want to form faithful partnerships with men who will help raise those children. But reality is more complicated. We now know women cheat, too. Researchers have found that females of “monogamous” bird species seem to have affairs in order to land the best genes for their babies. Evolutionary scientists have long speculated that what applies to sparrows and roosters applies to human beings, too.

B
REAKING
U
P

One night Rob didn’t call Melissa after he said he would. It was unlike him, and she started to freak out with worry. Was he hurt? Was he with another woman? Melissa could feel her fear physically. Strangely enough, the state of romantic love can be reignited by the threat or fear of losing one’s partner—of being dumped. Being dumped actually heightens the phenomenon of passionate love in the brain circuits of both men and women. That brain region desperately, hungrily seeks the loved one. Withdrawal—as if weaning from a drug—takes over. Moments of feeling as if your very survival is threatened occur, and a state of fearful alert is triggered in the amygdala. The anterior cingulate cortex—the part of the brain that engages in worry and critical judgment—starts to generate negative thoughts about losing the beloved. In this highly motivated, attentive state, obsessive thoughts of reunion take hold. This state elicits not trust and bonding, but painful, intense searching for the beloved. Melissa became crazed with thoughts of losing Rob. The part of herself that had become merged and expanded by his opinions, interest, beliefs, hobbies, mannerisms, and character was now in acute emotional, physical, and cognitive withdrawal, deep within the reward-driven areas of the brain.

The exhilarating expansion of the self that happened rapidly during the romantic-rush stage of love is now in a painful retraction. And when women experience betrayal or loss of love, they also respond differently than men do. When love is lost, abandoned men are three to four times more likely to commit suicide. Women, by contrast, sink into depression. Jilted females can’t eat, sleep, work, or concentrate; cry all the time; withdraw from social activities; and
think
about suicide. My eighteen-year-old patient Louise, for example, had been inseparable for two years from her boyfriend, Jason, until the afternoon he left for college. He suddenly ended their relationship, telling her that he wanted to be free to date other girls while he was away. Four days later, I got an urgent call from Louise’s father. She had been lying on the floor wailing inconsolably, not eating or sleeping, calling for Jason and moaning that she would rather die than to be without him.

Louise was hurting—literally—from the loss of love. Until recently, we thought that phrases like “hurt feelings” and “broken heart” were simply poetic. New brain-imaging studies, however, have revealed their accuracy. Rejection, it turns out, actually hurts like physical pain because it triggers the same circuits in the brain. Brain scans of people who have just been jilted by their beloveds also show the chemical shift from the high activity of romantic love to the flat biochemistry of loss and grief. Melissa wasn’t quite to this point yet. Without love’s surges of dopamine, the depression-despair response descends on the brain like a black cloud. This is what happened to Louise, but not to Melissa. Rob didn’t even realize that he was supposed to call her that night and had gone out to play poker with the boys. When he realized how much he had hurt Melissa, he apologized and promised always to call her. This episode made both Melissa and Rob realize how essential they had become to each other and actually motivated them to take the next step toward making their relationship permanent. They got engaged.

It may be that the “brain pain” of lost love evolved as a physical alarm to alert us to the dangers of social separation. Pain captures our attention, disrupts our behavior, and motivates us to ensure our safety and end our suffering. Given the importance for human survival of finding a mate, reproducing, and gaining food, nurturance, and protection, the pain of loss and rejection is likely hardwired in our brains so we’ll avoid it—or at least move on quickly to another mate, who’ll sweep us off our feet on a new, rapturous dopamine-and oxytocin-intoxicated high. What’s the trigger for this high? Sex.

FOUR

Sex: The Brain Below the Belt

F
INALLY, EVERYTHING WAS
in place. Her mind was calm. The massage did the trick. Vacation was always the best place. No work, no worries, no phone, no e-mail. No place else for Marcie’s brain to run. Her feet were even warm, and she wasn’t thinking about getting up for a pair of socks. He was hot—and a great lover. She could let go and let it happen. Her brain’s anxiety center was shutting down. The area for conscious decision making wasn’t lighting up so intensely. The neurochemical and neurological constellations were aligning for orgasm. Blast off.

Female sexual turn-on begins, ironically, with a brain turn-off. The impulses can rush to the pleasure centers and trigger an orgasm only if the amygdala—the fear and anxiety center of the brain—has been deactivated. Before the amygdala has been turned off, any last-minute worry—about work, about the kids, about schedules, about getting dinner on the table—can interrupt the march toward orgasm.

The fact that a woman requires this extra neurological step may account for why it takes her on average three to ten times longer than the typical man to reach orgasm. So girls, tell your man to slow down and be patient, especially if you’re trying to get pregnant. Research has shown that the biological reason for males coming more quickly is that females who orgasm after the male has ejaculated are more likely to conceive.

It’s a delicate system, but the connection to the brain is about as direct as it gets. Nerves in the tip of the clitoris communicate straight to the sexual pleasure center of the female brain. When those nerves are stimulated, they boost electrochemical activity until it hits a threshold, triggers a burst of impulses, and releases bonding, feel-good neurochemicals such as dopamine, oxytocin, and endorphins. Ah, climax! If stimulation of the clitoris is cut off too soon, if the clitoral nerves aren’t sensitive enough, or if fear, stress, or guilt interfere with stimulation, the clitoris is stopped dead in its tracks.

Marcie came to see me when she met John. She had had her first long, deep relationship, with Glenn, in her early twenties, but it didn’t last, even though he was a good-looking guy and it had become a comfortable relationship in which she felt totally secure. She had really enjoyed their sex life and always had great orgasms with him, but he wasn’t the man she wanted to marry. When she started dating again and hooked up with John, she found her body didn’t respond as readily. It was not that John was a bad lover or had inadequate equipment. Just the opposite. He was more fun and even better looking than Glenn. But John wasn’t Glenn, the man she’d grown comfortable and safe with. John was new, so she felt tense with him and couldn’t have an orgasm. One day Marcie went to the doctor with a bad neck spasm, and he prescribed Valium to relax the muscle. She took a pill at dinner, and by the time she and John fell into bed and had sex, orgasm was no problem. The Valium had relaxed her brain, her amygdala was deactivated, and she was able to reach the neurochemical threshold of orgasm easily.

If you’re not relaxed, comfortable, warm, and cozy, it’s not likely to happen. In a brain-scan study of female orgasm, researchers discovered that the women needed to be comfortable and have their feet kept warm before they felt like engaging in sex. For many women, being relaxed—thanks to a hot bath, a foot rub, a vacation, or alcohol—improves their ability to have an orgasm, even with partners they don’t feel completely comfortable with.

Women deeply in love and in the early phases of passion, who feel that their partners desire and worship them, are more likely to have easy orgasms. For some women, the state of security offered by a committed relationship or marriage can allow the brain to reach orgasm more easily than with a new person. As the orgasm subsides, waves of oxytocin cause a woman’s chest and face to flush because the blood vessels expand. A glow of contentment and satisfaction surrounds her. Fear and stress are blocked out. But how this all happens remains a mystery to the men around us. Every woman has had the experience of lying in bed with a guy who asks, “Did you come?” Often, it’s just hard for him to tell.

Because of the delicate psychological and physiological interconnection, female orgasm has been elusive to confused male lovers—and to scientists. For decades women have volunteered to be prodded, filmed, tape-recorded, interviewed, measured, wired, and monitored by scientists. The shortened breath, arched back, warm feet, grimacing face, unintentional vocalizations, and jumping blood pressure of women’s orgasm have all been measured. And now, because of MRI scans that show the activated and deactivated areas of the brain, we know much more about the female brain’s control of orgasm.

If we took an MRI scan of Marcie’s brain as she headed for the bedroom with John, we’d find that many of her brain circuits would be highly activated. As she snuggled down between the warm sheets, cuddled up to John, and started kissing and hugging, certain areas of her brain would become more calm and the areas for genital and breast sensitivity would begin to light up. As John began to touch her clitoris, her glowing brain areas would start to spark red, and as she grew more excited while he rubbed her clitoris, her brain area for worries and fear—the amygdala—would deactivate into a calm blue. As she became more excited and pulled him inside her, the amygdala would completely deactivate and the pleasure centers would pulse red until—bingo—rapid, pulsing waves of orgasm flooded her brain and body.

For a man, orgasms are simpler. Blood has to rush to one crucial appendage for sexual climax to take place. For a woman, the neurochemical stars need to align. Most important, she has to trust who she’s with.

Since the male model of arousal is basic hydraulics—blood flows to the penis, leading to erection—researchers have looked endlessly for the same simple mechanism in women. Doctors have surmised that women’s arousal problems stem from low blood flow to the clitoris. There’s never been any evidence, however, that this is true—and no researchers have ever found ways of measuring physical changes in the clitoris when it’s aroused. Instead, they’ve groped for other indicators, such as lubrication, using clumsy methods such as weighing tampons before and after female research subjects watch erotic films. Scientific understanding of female sexual response is still decades—if not centuries—behind research on male erections, and the progress remains frustratingly slow. Even a recent anatomy textbook completely omitted a description of the clitoris while giving a three-page description of the penis. Medical doctors still feel that if a man can’t get an erection, it is a medical emergency, but no one seems to feel the same urgency about sexual satisfaction for women.

Since Viagra’s explosive debut in 1998, scientific interest in sex differences has heated up. Drug companies have been falling over themselves trying to find a pill or patch that can reliably kindle female desire. So far their efforts to discover a pink Viagra for women have been a bust. In 2004, Pfizer officially ended its eight-year quest to prove that Viagra boosted blood flow to the clitoris and therefore increased sexual enjoyment in women.

We now know for sure that, just as the female brain is not a smaller version of the male brain, the clitoris is not a little penis. The entire ring of tissues that surrounds the vaginal opening, the urethra, and the outer third of the vagina is connected by nerves and blood vessels to the tip of the clitoris—so all these tissues together are responsible for the excitation leading to orgasm. Some women refer to this area as their “ring of fire.”

There is also no such thing as a vaginal versus a clitoral orgasm, as Freud erroneously thought. For nearly a century, his theory made women feel they were inadequate or not quite real women if they
only
had clitoral orgasms. Freud knew nothing at all, of course, about the anatomy of the clitoris or that of the female brain. Neuroscientists have discovered that the vagina is connected to the clitoris, and therefore the female orgasm is all from this one organ, which is connected to the pleasure centers in the brain. The clitoris really is the brain below the waist. The action, however, is not all below the waist, nor is it all guided by psychological factors. To the modern neuroscientist, the psychological and the physiological are not different—they are just opposite sides of the same coin.

I
T
D
OESN’T
T
AKE
M
UCH TO
S
POIL THE
M
OOD

Bad breath, too much slobber, a clumsy move with a knee, hand, or mouth, any little thing can spring the female amygdala back into action, cutting sexual interest and orgasm off at the pass.