POSTCOITAL NARCOLEPSY
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.
warm, safe feelings 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.
FIVE
The Daddy Brain
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.
two different hunter-gatherer
A DAD IS MADE
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.
"When he looked into my eyes, I think he knew I was his dad and I would always protect him," Tim later told me. The skin-to-skin contact between father and son had worked its biological charms on both of them, calming them and promoting bonding.
Because infants require round-the-clock care for survival, Mother Nature has forged a nearly unbreakable biological bond between parent and child. It's as if she waves her magic wand over the parents' brains and they fall head over heels in love with their baby, as Tim and Michelle were discovering. Scientists have learned that the same brain circuits that were activated when Tim and Michelle fell in love were now being hijacked to make sure they fell in love with Blake. Cupid's arrows were being dipped in powerful neurochemicals like dopamine and oxytocin. Just as in romantic love, the connections between the baby's and parents' brain circuits are reinforced by skin-to-skin contact and gazing into each other's eyes and faces. And researchers have s
hown that a baby's face, with its soft, pudgy cheeks and large eyes, activates a special brain area called the parental-instinct area within a seventh of a second. Tim and Michelle's instincts were turned on full blast.
DAD'S TENDING INSTINCT
"That little fellow sure has a good set of lungs," Blake's grandfather said as his daughter swooped into the room and popped the pacifier back into Blake's wailing mouth. Crying is a universal caretaking cue, but it stimulates the brains of fathers and mothers differently. Fathers' and mothers' brains light up in similar areas when they hear a baby cry. But the mommy brain activates more intensely, which may be why she's compelled to stop the crying before the dad feels compelled. So when Blake cried, Michelle almost always got to him first, even if Tim was closer. He was astonished by how quickly she heard and responded to their son's every whimper. But Tim's tending instinct and response to Blake's cries were improving daily.
As it turns out, the tending instinct is prewired into all human brains, not just mothers'. If we could have taken a brain-scan camera inside Tim's head as he cared for Blake, we'd have seen his amygdala, his worrywart ACC, and his insula--the area for gut feelings--light up as he heard Blake crying. Then, as Tim playfully changed Blake's diaper and kissed his soft stomach, the gleeful smile on his son's face would trigger his brain's reward center, the NAc, or nucleus accumbens. At this moment, all the circuits of Tim's daddy brain would be pulsing with the joy of fatherhood. Tim's brain was being stimulated to make new connections to reinforce his tending instinct. And each new connection in his brain helped him to get more in sync with his son.
FATHER-INFANT SYNCHRONY
New fathers are often surprised by how much they want to hold and play with their babies. The making of a daddy brain requires not only hormones and paternal brain circuits but also physical touch. At Princeton University, researchers compared dads and non-dads in our primate cousins the marmosets. Marmoset dads are probably the most involved fathers on the planet, holding their newborns more than fifteen hours a day, every day, for the first month. Carrying the infants for so many hours each day aligns the dads' brains with their offspring. The researchers found that the area of the marmoset dads' brains for thinking and predicting consequences, the prefrontal cortex (PFC), showed more cells and connections than in the non-dads. This brain area has receptors for the so-called fathering hormones: prolactin, oxytocin, and vasopressin. These scientists concluded that the experience of being a hands-on father dramatically increases the number of connections in the male brain for paternal behavior. Brain-scan studies show that contact between parent and child also activates the PFC in humans. So even though moms' brains may be on higher alert from day one, it's now clear that dads' brains can quickly catch up. Tim didn't need a brain scan to tell him what he already knew--that the same brain that used to be glued to Sunday football was now completely absorbed with Blake.
Because Tim had been involved from the day Blake was born, his daddy brain circuits were now running like a well-oiled machine. Even though Blake couldn't talk, he and Tim had been establishing an understanding and getting to know each other. Researchers' technical word for this parent-child understanding is synchrony. Synchrony is like an extended series of volleys in a tennis match. Some examples are tickling, eye contact, laughter, and teasing. This back-and-forth interaction in games like peekaboo is critical for developing parental behavior, according to studies by Dr. Ruth Feldman. Many fathers who don't have daily hands-on contact may fail to form the strong daddy brain circuits required for parent-child synchrony. The environment for eventually establishing such a close interaction may start before birth. During the last months of my pregnancy, my son's father would play a tapping game with him. His dad would tap tap tap on my belly, and he'd tap tap tap back--kicking seemingly with the same rhythm. The father-son relationship had begun.
DADDY AND MOMMY ARE DIFFERENT
Soon after birth, a baby can tell the difference between Mommy and Daddy. Within weeks of being born, Blake could see and smell the difference between Michelle and Tim, and he could hear and feel the differences too. Daddy had a deeper voice. Mommy had softer hands and talked as if she were singing. Even in the dark of night, Blake knew which parent was bending over his crib to take care of him. But Tim confessed that he couldn't help feeling a little jealous that Blake often seemed to want his mom more--and Michelle seemed to sometimes prefer Blake to Tim, too. As Tim was discovering, for fathers, early on, it's hard to match the biological force of the love bond between Mommy and baby. The baby is initially more bonded with the parent who has the yummy milk-filled breasts, and the intense pleasurable sensations of breast-feeding reinforce the mother's bond with her baby.
Scientists believe that the emotion and communication centers in the baby's brain learn to relate differently to Mom and Dad. This doesn't become obvious to the parents until the baby is about three months old and begins spending less time sleeping and more time interacting. At this age, Dad begins to play a starring role in baby's life. By the time Blake was six months old, he loved the stimulating games Tim played with him. When Tim kissed Blake's belly and blew loudly against his skin, tickling him, they were in their own private world.
ALONE TIME WITH DAD
Research shows that dads behave differently with their babies not only when the moms are away but also when the moms aren't watching. And infants notice the difference, too. One study showed that when Mommy, Daddy, and baby were all together, there were fewer interactions between Daddy and baby. And when fathers were alone with their babies, their playtime was much more spontaneous.
Establishing this comfortable spontaneity requires spending one-on-one time together, but some fathers, like Tim's brother Mike, either don't take or don't have this opportunity. Tim said the last time he stopped in at Mike's, he saw Mike's wife, Cynthia, snatch their eight-month-old son, Nathan, from his arms when the baby began to whine. Mike had been complaining for months that Cynthia didn't trust him, often criticizing or correcting his parenting. Tim said Mike had been looking forward to being a dad and imagined himself having fun with Nathan, but apparently Cynthia had a different plan. The only time she handed the baby to Mike was when her mother wasn't there. Then she'd thrust Nathan into Mike's arms the instant he walked in the door after work. Researchers at Ohio State University found evidence that fathers' beliefs about how involved they should be in child care didn't matter; it was mothers who were in the driver's seat. They discovered that moms are the gatekeepers for fathers' access to their children. Mothers can be very encouraging to fathers and open the gate to their involvement, or they can be critical and close the gate. Cynthia was a negative gatekeeper and didn't trust anyone with Nathan except herself and her mother. She was unknowingly operating on ancient brain circuitry that told her that female kin were the ones she could look to for help.
Whereas many fathers feel overwhelmed by being the family's main provider and also being expected to help equally with child care, Mike was begging for more time with his baby and couldn't get it. Tim was grateful that Michelle trusted him with Blake and didn't expect him to fill the "ancient shoes" of all her female kin. Michelle was also strengthening her marriage by letting Tim be a dad. Researchers have found that moms who are the least critical of their husbands and encourage the dad's interactions with the child fare best when it comes to staying together.
DADDY TIME IMPROVES SELF-CONFIDENCE
At twelve months, Blake climbed all over Tim as if on a human jungle gym and was constantly trying to pull his daddy to the floor so he could wrestle with him. When he succeeded, he'd triumphantly sit on Tim's chest grabbing his dad's face hard with his tiny hands and squeezing his chin or cheeks. Even at this age, Blake loved to test his skills with his daddy, and he loved it when Tim swung him into the air and back down again, trying to snag Tim's sunglasses or hair whenever he got close enough. Father and son playfully challenged each other at every turn.
Researchers have shown that the particular way father
s play with their children makes their kids more curious and improves their ability to learn. Compared with mothers', fathers' play is more physical and boisterous. The researchers found that daddy play is more creative and unpredictable and thus more stimulating. Fathers' creativity shows up not only while playing but also while talking and singing to their children. Researchers at the University of Toronto found that mothers sang the correct versions of "Twinkle, Twinkle, Little Star" or "The Itsy-Bitsy Spider," and fathers altered the verses, creating complex songs with unpredictable endings. The dads were more quirky and fun.
And that's not the only difference. In another study, in Germany, scientists followed a group of children for fifteen years. They first began observing the fathers interacting with their children at two years of age. They found that the children whose fathers played roughly with them, the way Tim played with Blake, were the most self-confident by the time they reached adolescence.
TEASING: THE SPIRIT OF MALE COMMUNICATION
Physical and verbal teasing is the way dads connect with their kids. Michelle wasn't thrilled when, thanks to Tim, five-year-old Blake's favorite phrase had become "You're a poo-poo head," which he would often say while vigorously pointing to his rear end. But for Blake and Tim, it was just part of their fun.