The Male Brain (12 page)

"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 shown 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.

"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.

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.

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.

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
.

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 fathers 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
.

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.

Dads employ teasing with sons and daughters, but their daughters usually don't like it as much as their sons. Daughters will soon try to divert Dad and assign him a part in the role-playing games girls prefer. (And most dads are usually willing to go along with whatever roles their little girls give them.) Boys, on the other hand, love the teasing games and will actively egg Dad on, trying almost anything to get his goat. Researchers have found that this kind of father-child play improves children's ability to guess what's on another person's mind and to
recognize mental tricks and deceits
. And for sons, this playful teasing with Dad establishes the foundation for building close connections with other males later in life. By the time Blake was six, he and Tim could banter mock insults for longer than Michelle could stand to listen.

The next time I saw Michelle, she was annoyed with Tim. "Sometimes he barks orders at Blake like he's a drill sergeant," she said. "He'll practically bellow, 'Sit down, don't move, be quiet.' Even though Blake doesn't seem to mind, I think Tim is being insensitive and rude." I had heard this many times before. To mothers, fathers can sound too harsh, and to fathers, mothers can sound too soft.

Researchers have indeed found that fathers give their children
more direct orders than mothers do
. And mothers stay emotionally in tune with their children more, so they don't need to give as many direct orders. Mothers use shorter sentences and match their children's tone of voice more than fathers do. Michelle was right--Tim's style
was
rougher than hers, but not better or worse. Researchers believe that daddy talk provides an important bridge to communicating in the real world, where children will soon find that others can't read their minds or anticipate every need the way Mom does.

Discipline was another area where Tim and Michelle differed in style. Tim thought it was his duty to guide Blake's development by using firm rules and strict corrections. And he was not alone.

Researchers have found that fathers in cultures around the world believe it's their job to make their children,
especially sons, toe the line
. Of course, fathers must walk a fine line between overly harsh punishment--which creates fear, distrust, and a desire for revenge--and "just right" discipline. And even though some modern parenting styles endorse the laid-back father as more likely to be a good dad than the high-testosterone macho man, biological research suggests that the opposite may be true.

Male parents across the animal kingdom are typically more strict than female parents and more aggressive in handling their offspring. Although we don't think of aggressive males as being better dads, for some fathers, like rodents, being a good dad requires being rough-and-ready. A rodent dad must be aggressive and forcefully grab and retrieve runaway pups, or they will die. As with human dads, the rodent dad's paternal brain circuits are fueled by
the hormones testosterone and vasopressin
. The researchers discovered that the most aggressive rodent dads had the highest levels of these hormones. And interestingly, they also found that the most aggressive male pups grew up not only to have the highest testosterone but also to
be better, more protective dads
.