The Male Brain (11 page)

When Matt reached the point of no return, his brain released all the brakes and he emitted a deep, involuntary groan. As he climaxed, his brain circuits and body were flooded by norepinephrine, dopamine, and oxytocin, increasing his ecstasy. Simultaneously, his brain area for intense pleasure, the ventral tegmental area (VTA), and his brain area for pain suppression and vocalization--the
periaqueductal gray (PAG)--activated intensely
. Tonight, Matt's timing was perfect, and he felt his partner's vagina contracting with the waves of her orgasm at the same time that he had his--intensifying the pleasure for both of them.

Until men learn to inhibit the sex-arousal centers in their brains, the tail wags the dog, and they often reach orgasm long before their female partners have a chance. For reasons scientists don't completely understand, it typically takes women seven to eighteen minutes of vaginal intercourse to climax, and Matt was pleased that he'd already mastered the self-control
problems of his early twenties
. Scientists have discovered a group of neurons in the spinal cord called spinal ejaculatory generators that can be turned on
or off by the brain
. To gain dominion over the brain below his belt, a man must learn to direct his focus from his brain's sex centers to a nonsexual area. Tricks men may use to accomplish this include mentally solving complicated math problems, silently reciting the alphabet backward, or activating the disgust center, the insula, by thinking of something revolting. But when his penis is being pumped up with ten times the normal amount of blood, trying to stop an orgasm can be like trying to stop a runaway train. Perhaps that's why up to 40 percent of young men climax in fewer than eight to fifteen penile thrusts. According to researchers, more experienced men like Matt can teach themselves to last for
seven to thirteen minutes or more
.

Matt was glad that he finally had some staying power and that his days of hair-trigger ejaculating were well behind him. A condition called premature ejaculation, or PME, can be a source of embarrassment for men and frustrating for them and their partners. Also known as rapid ejaculation, it affects between 25 and 40 percent of men in the United States, and most men have
experienced it at least once
. Aside from a lack of physical control, it can be caused by a variety of psychological factors, such as stress, depression, a history of sexual repression, and unrealistic expectations fostered by the media about men's performance.

Men who have high expectations about their sexual performance can sometimes experience an inability to become erect or stay erect long enough to have sexual intercourse. When Matt came in to see me about having this sort of trouble, he told me that he'd never experienced it until recently, and he was worried that something might be wrong with him. After dating a variety of women for several months and having no sexual difficulty whatsoever, Matt met a woman named Sarah, whom he was more into than any other woman he'd ever met. Sarah was a twenty-nine-year-old dancer with a gorgeous face and a body to match. He said, "I didn't want her to think I was just after her body, so we went out a couple times before I even made a move." He wanted her to trust him and feel comfortable before they had sex because he knew she'd need to be relaxed to have an orgasm. And he was determined to give her the best one she'd ever had.

But he was horrified to find that he'd put so much pressure on himself that when the time finally came to have sex, he could only get semierect. He was afraid she'd take this as a sign that he wasn't that into her, when in fact the opposite was true. Many men have told me that their "stage fright" is proportional to how hot the woman is and how much they want to impress her. This is when the so-called simple hydraulics of a man's sexual system can stall.

As a matter of fact, Matt's worrywart and performance-anxiety center, the ACC, was shutting down his spinal generators for erection, as well as his capacity to relax. This meant he couldn't stay hard enough to penetrate. Deep in his brain, his amygdala and ACC were triggering the fight-or-flight system in his sympathetic nervous system (SNS) and thereby turning off the neurochemicals in his hypothalamus and parasympathetic nervous system (PNS) that are needed for an erection. The PNS induces the chemical relaxation response that allows the blood vessels in the penis to open up and fill with blood, thus
achieving an erection
. When a man feels relaxed, his brain's PNS and oxytocin cells release oxytocin down the spinal nerves to aid in penile erection. So the correct balance between the PNS and SNS is crucial for a man to get an erection.

Matt was very worried that if this happened to him again, Sarah would think something was wrong with him and his chances for an ongoing relationship with her would be shot. He wanted me to prescribe a Viagra-like drug as "insurance" so he could be sure to
get the erection he wanted
. (Drugs like Viagra keep blood inside the penis to get and maintain an erection.) He said, "I've read about guys who had this performance problem happen, and once it happens again, it can become 'a thing' and keep happening." Matt was right. A man's anxiety over a previous failure can lead to more failures. This sort of performance anxiety can happen to men at any age, but because Matt was in his early thirties, I thought he could probably eliminate his difficulty by being more relaxed before he had sex with Sarah again. An intense physical workout before a date can sometimes do the trick, and some studies show that one or two alcoholic drinks may aid the relaxation response too. "Don't have more than two drinks, though," I warned him, "since as you probably already know, too much alcohol can make erection almost impossible."

The next time Matt came in to see me, he was feeling good about himself. He said the combination of a two-mile run and a couple of beers had worked for him, and things were going very well with Sarah. But after a couple of minutes of bringing me up to date on how things were going, he asked, "One other thing I wanted to ask you is whether it's normal or not to fall asleep right after sex."

I told him that this is something nearly all women complain about; they think it's a sign that the man doesn't care enough about them to stay awake and cuddle for a while. But the truth is that the hormone oxytocin is to blame for a man's so-called Oxytocin promotes pleasurable, during and after sex for both men and women. In the female brain, the oxytocin and dopamine released after orgasm make her want to cuddle and talk. But research shows that this postorgasmic blast in men may lull them to sleep as it's released into their hypothalamus,
triggering the brain's sleep center
. I said, "For reasons we don't yet understand, in men it works a lot like a sleeping pill."
postcoital narcolepsy.

Indeed, it turned out that Sarah
had
felt neglected when he fell asleep after sex. However, he wanted to do everything he could to keep her in his life. He told me, "There's some truth to the stereotype that guys care most about sex, sports, and beer, but a lot of us want a long-term relationship, too. I have a good connection with Sarah, and even though we've only been going out a couple months, I think things could end up getting serious."

I was pleased that Matt had regained the courage to consider a long-term relationship again. He'd mentioned more than once that he'd like to have a family someday, and I had a suspicion that if things continued to go well with Sarah, she might end up being his wife and even the mother of his children.

OH, SHIT! This can't be happening
, Tim thought to himself as Michelle showed him the bright pink line on the home pregnancy test. Tim, a muscular thirty-four-year-old contractor, had that deer-in-the-headlights look as he tried to hide his panic from his wife. They'd been married for just six months, and although Tim wanted kids, it was too soon. In their initial couples-therapy session, they told me they were planning to wait a few years before starting their family. This wasn't following their blueprint. Now the words his older brother Mike had said were haunting him: "Fatherhood changes your life forever, dude."

Mike was right. Some men are over the moon about their wife's pregnancies, but studies show that feelings of distress peak for most men four to six weeks after they discover
they're going to be fathers
. They seldom reveal these worries to their mates, and Tim's way to handle anxiety about being a father turned out to be by arming himself with information. He asked me to suggest some books on pregnancy, childbirth, and parenting. He also went online for information, and it turned out that some of what he read just raised more fears. For example: "The way parents tend to a baby's needs during the first weeks and months after birth can shape the baby's brain for
the rest of its life
." By the time Michelle had her three-month prenatal visit, Tim's nerves were
more
jangled, not less.

The turn for the better came when Michelle lay on the table for her first ultrasound. Tim was sitting alongside her as the doctor rubbed cold gel on her belly and turned on the machine. When a baby's image appeared on the screen, Tim audibly gasped as he saw its heart beating. "It was like nothing else mattered," he said. "All I could do was stare at this tiny beating heart and think, 'Oh my god, that's
my
child.'"

Scientists now know that a man's brain changes as his mate's pregnancy progresses. Dads typically don't crave pickles with ice cream or wake up nauseated every morning as moms do, but they do have emotional, physical, and hormonal shifts in parallel with their mates' pregnancies. Research at Harvard University revealed that two major hormones change in fathers-to-be: testosterone goes
down and prolactin goes up
. Scientists believe that men may be responding to the natural airborne chemicals of pregnancy--pheromones--emanating
from the mother-to-be's skin and sweat glands
. Unbeknownst to him, these hormones are priming him for paternal behavior. In some men, this hormonal shift can cause couvade syndrome--"
sympathetic pregnancy
." Couvade syndrome has been documented in fathers-to-be worldwide, and Tim was experiencing it firsthand. By the beginning of Michelle's second trimester, she needed bigger clothes--and so did Tim. He'd gained fifteen pounds.

And in a biological tit for tat, at least in mice, the father's pheromones have been found to waft through the air and into the mother's nose and trigger her to make more prolactin, a hormone that increases the
growth of maternal brain circuits
. The mommy brain begets the daddy brain, and the daddy brain abets the mommy brain.

As Michelle's belly and due date loomed large, she spent hours refolding tiny baby clothes and blankets and collecting all the other baby supplies she thought they'd need. Meanwhile, Tim was also "nesting." He became obsessed with fixing up the house, painting the baby's room and building shelves for all the new infant equipment, books, and toys. Scientists have found that men have the biggest hormonal leap from non-dad to dad in the days leading up to the birth. Researchers studied fathers-to-be during the last trimester of their wife's pregnancy and found that these men's prolactin levels increased by over 20 percent and their testosterone dropped 33 percent during
the three weeks before birth
. And by the time their children were born, not only had the fathers' testosterone dropped, but they were better at hearing and emotionally responding
to crying babies than non-dads
were. On average, a man's testosterone and prolactin levels will begin to readjust when the baby is six weeks old, returning to prefatherhood levels by the time the baby is walking.
In cultures around the world there is a lot of variability among fathers. Dads who are actively involved in taking care of their children have been found to have lower levels of testosterone Researchers compared cultures, one in which fathers give a lot of hands-on care and another in which
fathers give very little care
. Hadza dads, who give more hands-on care, had lower testosterone levels than the dads in the Datoga tribe. Datoga dads have very little contact with their children, and they had higher testosterone, closer to the levels of the single men in that tribe. No one knows for sure whether the different hormone levels cause the behavior or whether the hands-on fathering suppresses testosterone.
than uninvolved fathers.

A week after Michelle's due date, Tim rushed her to the hospital as her contractions intensified. For the next thirty-six hours, he stayed awake, helping her to breathe through the contractions and trying to make her feel more comfortable, which seemed like an impossible task. During the birth itself, Tim couldn't believe how hard Michelle had to work. He was never so glad to be a man. Twice he felt he might faint. And then suddenly he could see the crown of the baby's head, and he became completely transfixed as the entire head and shoulders began to emerge. When the doctor handed Tim his newborn son, tears welled up in his eyes as he snuggled naked little Blake against the bare skin of his chest and neck.