Love at Goon Park: Harry Harlow and the Science of Affection
To frame the experiment in Bowlby’s theory, the fostered infants also appeared to be unusually securely attached. When the monkeys were six months old, the scientists experimentally separated them from their foster mothers. The little animals were definitely stressed. They devised a coping strategy, though. They recruited friends. And they kept those friends—it appeared that they were just likeable monkeys. The babies raised by their own nervous and preoccupied mothers were—not surprisingly, if you think about it—insecurely attached. They were timid with others. Their shyness made them unusually slow to befriend others. They were more traumatized by separation. And they tended to live separately. The nervous monkeys raised by nervous monkeys tended to become loners. Social contacts were too much. They often dropped to the bottom of the monkey hierarchy.
Suomi tracked the young monkeys from both groups until they became parents themselves. The nervous little monkeys grew into nervous mothers, continuing the cycle. Despite being born with that same antsy biochemistry, the cross-fostered monkeys parented like their sweet-natured foster mothers. Clearly, the benefits of affection and kindness rippled right through to the next generation. Suomi’s study, in part, provided another reminder that genes are not destiny. It reinforced that lesson from Harry’s lab—that the mother we are born with is not always the mother we need. And again it supported Bowlby’s belief that the best lives have a secure base at the center. “Whereas insecure early attachments tend to make monkeys more reactive and impulsive, unusually secure attachment seems to have essentially the opposite effect,” Suomi wrote. He was talking about the monkeys in his study only, of course, but it’s safe to say that both John Bowlby and Harry Harlow would have been comfortable in applying that lesson to the rest of us.
There are several reminders in that elegant NIH experiment: that we need not grow up to be our mothers; that we may not want to; that it’s not easy to change. And that it may be unfair to load all our expectations and needs onto one parent, anyway. With the best intentions in the world, one person may not be able—or intended—to give a child everything he or she needs. The extended family, even the right child care provider may be exactly what’s needed.
The perils of depending too much on the one, the only relationship, are beautifully illuminated in yet another primate experiment by another one of Harry’s former graduate students, Leonard Rosenblum of SUNY-Brooklyn. Rosenblum compared pigtail and bonnet macaques. Bonnet babies grow up in a kind of bubbling community of friendly females. Although the mother cares for them, they are also enveloped by the other adult females who help raise them. In the words of Rosenblum, the bonnet infants are both mothered and “aunted.” Pigtails are mother-raised only. Their watchful female parents keep them very close to home. If Rosenblum took mother out of the home cage, both pigtail and bonnet babies wailed with fear and loss. But the bonnets then quickly went to their “aunts” as a coping strategy. A little pigtail had no one to seek for comfort. The baby would call for his mother. The small monkey would then lapse into depression, hunch over, refuse even to look at other monkeys. Watching baby pigtails, you could wish them a few of those aunts.
In her book Mother Nature, California anthropologist Sarah Blaffer Hrdy builds an image of the good mother very different from that 1950s lonely but devoted nurturer. The mother Hrdy has in mind is also fiercely protective of the child, of course, but sometimes she is just plain fierce. Hrdy would have us get rid of that milky Madonna stereotype. She reminds us that mothers are still women with passion, and ambitions, and, yes, interests beyond the child. And as long as we are getting rid of stereotypes, Hrdy points out, there’s no reason to assume that human beings should function like pigtail macaques, each mother solely responsible for her young. Why shouldn’t we be like bonnet macaques, connecting in that more giving community of aunts or uncles or cousins or grandparents? Why should we cast the social support net so very narrowly?
Harvard child psychologist Ed Tronick also wonders about the one-on-one bond, what Tronick calls a monotropic relationship. He and his colleagues studied Efe pygmy infants as a way of exploring other parenting arrangements. An Efe baby, for at least the first four months, spends more than half of her time with adults other than her mother. Friendly adults cycle through the baby’s life. There may be five helpers an hour, depending on who has time to share. The resulting bonds appear to be almost communal. Babies clearly recognize their mothers and fathers, but they may also attach to several adults. Adults, in turn, may form close bonds with several babies other than their own. Hrdy calls this kind of shared care “allomothering.” Her view of allomothering encompasses both the natural tribal version and the twentieth-century modern American version, which can be paid day care, done well, done properly, with affection and stability.
“It’s an experiment that we’ve got running,” says Meredith Small, author of Our Babies, Our Selves. “We have nonrelatives with the kids. It’s okay if they become like an extended family. The really important issue is not whether the toddler is learning colors and how to read at age three, but does that teacher hug your kid?” If we aren’t going to return to the closely linked extended family, re-create ourselves in the Efe model, perhaps we need to make sure that our day care centers are more like families than tidily ordered schools. Craig and Sharon Ramey, at the University of Alabama, have tested superintensity preschool programs for children, mostly children from disadvantaged families who are likely to have highly distracted parents. Consistently, the children in those programs thrive. Ramey suggests that his prototype day cares—one to three ratio, lots of hugging and touching—are designed to mimic the extended family nature of human evolution. “Whether it’s a child in the inner city kept inside for safety or whether it’s an only child on a suburban two acres, the effect is the same,” Ramey says. “We have to find ways of countering the isolation of the family.”
We might also, in these more modern times, consider further emphasizing the role of the father. For all that he was an unlikely champion of heart-to-heart fathering, Harry Harlow saw that possibility in his research. He was one of the first, wrote psychologist Joseph Notterman in The Evolution of Psychology, “to recognize the liberating function” of those shared abilities and the father’s ability to “thereby share in the development of infant love.” Harry wasn’t a natural champion. He studied rhesus macaques, after all, a mother-centric species if ever one existed. But there’s nothing that says that solo mothering is a bred-in-the-bone primate characteristic. It’s not even a consistent macaque trait, if one considers those well-aunted bonnets.
Bill Mason and Sally Mendoza, at the University of California-Davis, have done some remarkable work with the South American titi monkey—as gorgeous a ball of fluff as ever perched on a tree branch—and found that titi females bond mainly to their mates. The females are not noticeably maternal. When titis have children, the males take responsibility for about 80 percent of the childcare. The father is the nurturing one, the caregiver. If the scientists lift the mother from the family temporarily, the baby shows a bare flicker of stress response. But if they take out the dad? The infant monkey’s cortisol rises like mercury on a hot day. Still, even titis confirm Harry’s famous point that we don’t merely love the warm body that feeds us. The titi mother nurses her baby for the first few months, as in any lactating species. It’s the dad who holds and carries the child. And it’s the dad who is beloved.
Chuck Snowdon, now head of the psychology department at the University of Wisconsin, has been working with another South American species, the cotton top tamarin. Cotton tops are tiny, darkeyed monkeys with white-tufted heads. They live in extended families that are not only closely related but also fully engaged in supporting each other. Tamarins form a social network that relies on each member to share in childcare duties. How do the babies fare under this team-handling approach? Brilliantly, it turns out.
Among the cotton tops, mother, father, aunts, and older brothers and sisters all pitch in to raise the infant. Mo
ther is the milk provider, but the baby attaches to the member of the family who spends most time with him. “When you look at all the caretakers—mother, father, oldest brother—when the baby is scared, he runs to the one who does the most nurturing,” Snowden says. Because they are wafted around in the group, the infants also receive a steady diet of attention. And if the mother turns out to be a not-very-good mother, bored and restless, the father or a brother will take over more of the baby duties. “So basically, what’s happening is one member of a family is compensating for the behavior of another,” Snowdon says. As in other species, there are mothers from whom, given a choice, a baby might want to be slightly separated. “There are restricting mothers, there are laissez-faire mothers,” Snowdon explains. “But if we look in our family of tamarins, the multiple caretakers buffer the effect the mother has. So if you were unlucky enough to have a weird mother, you’d be buffered. Of course, if you had a brilliant mother, that would be buffered some, too.”
As Harry’s work showed all too clearly, and as some of us know all too well, there’s no guarantee that you won’t end up with a weird mother or a bored mother or even a monster mother. “If you’re going to work with love,” Harry said, “you’re going to have to work with all of its aspects.” One of the risks of the one-on-one attachment is that you could end up with a brass-spike mother and no one else to hold you. As Snowdon points out, there’s a tradeoff. If you share in several caretakers, you may miss the advantage of getting the total attention of the world’s best mother. But you are never as vulnerable to the spiked parent. “Maybe we’re moving back toward more cooperative child rearing,” he says, “and my belief is that this is better.”
And maybe we are moving in that direction—or at least some of us are. One of the questions that arises, as one considers the variations in parenting across the primate world, is whether we humans are able to choose the direction. Are we such a flexible primate species that we can pick and choose among the best strategies of our monkey relatives? Or, like them, do we follow an inherent species pattern, intensively mothering like the pigtail macaque, delicately sharing out the responsibilities like the cotton top tamarin? How much room is there to negotiate one’s way to becoming the best mother possible? Or to avoid becoming the worst one?
Once again, we are left with one of those imperfect and complex answers. Clearly, some cultures, such as the Efe, do indeed practice a cotton top tamarin approach to life. Clearly again, Bowlby’s model was based more on the mother-first model of the rhesus macaques—not to mention those passionately imprinted greylag goslings. If you assume that the best clue to our basic biology is in the majority pattern, then you can’t simply dismiss Bowlby as an artifact from a less egalitarian society. Culture to culture, we still look mostly like a mother-centric species. That doesn’t mean that mother is the only option. But it should remind us that for human babies a central parent figure is absolutely, undeniably important. Someone in the family has to be paying full attention to that baby. Bowlby was right when he said those early attachments—to mother, father, or loving caretaker—are always among the most powerful influences in our lives. Where we may indeed be flexible is at the individual level, in paying specific attention to the needs of our own specific children. If that seems too small a beginning, there is plenty of research to assure us that even small gestures matter.
Consider one of the first and most deceptively simple results of Harry’s cloth-mother tests: that babies crave a soft touch. Since that time, researchers have been trying to figure out why. Why would a terrycloth-towel-wrapped mother be night and day compared to a wire one? What in our biology makes contact comfort so critical to healthy development?
The scientist who did some of the first and best work on the basic chemistry of touch is Saul Schanberg of the department of pharmacology at Duke University. Schanberg started in a non–Harry Harlow way, by looking at rats. Schanberg found that when mother rats licked their babies, the action produced a cascade of much needed compounds, in fact, the growth hormones that produce normal body development. Remove the mother—remove the touch of her tongue, and the baby rats became stunted beings. Put the mother back into the nest and the babies gratefully began to stretch outward and upward. In another reminder of the basic mechanics of motherhood, Schanberg also found that you could—at least with rats—simulate the mother’s lick with a wet paintbrush.
The Duke mother-touch studies fit smoothly into the evolutionary concept of Bowlby’s attachment theory. Schanberg suggested that the intense response to touch alerts us to a primitive survival mechanism, one that probably exists in many species. “Because mammals depend on maternal care for survival in their early weeks or months, the prolonged absence of a mother’s touch, more than forty-five minutes in the rat, for instance, triggers a slowing of the infant’s metabolism,” he wrote. If his mother was missing, the baby rat used less energy. That meant he consumed less fuel. And that meant he could survive a longer separation from the mother. All well and good as long as she wasn’t gone too long. Once she returned, Schanberg says, “The mother’s touch reverses the process, so that growth resumes at normal rates.” The baby who huddles into his crib and the little monkey who curls up at the edge of her cage appear hopeless. But we should be aware that some of the huddling is just conservation. It is a curious mixture of despair and hope. As they hunker down, the young animals are waiting for their mothers to come home and for everything to be all right.
Myron Hofer, at New York University, also explored the power of touch by studying rats. Hofer was a genius at considering the mechanics of mothering. He would take the mother rat out of the nest and substitute her essential elements: warmth, milk, stroking with a brush, sound (recordings of her squeaks); he even pumped her odor into the cage. Hofer found that only touch made a difference in how the little rats grew. So he brought the mothers back into the cages. There was one catch. He kept them under anesthesia, so there was no touch and nuzzle and lick. A mother’s inert presence helped not at all. The babies continued to quietly shrink away.
Schanberg then went on to do a classic study with Tiffany Field, at the University of Miami. The two researchers went back to Klaus and Kennell’s concern with preemies, but from a different angle. They weren’t looking at whether the infants bonded through touch, just whether the babies physically needed the human contact. Field and a crew of graduate students went into one preemie nursery and simply touched the babies. They did this just for fifteen minutes, three times a day. The touching was very deliberate—slow firm strokes, the gentle stretching of tiny arms and legs. The stroked infants grew 50 percent faster than the standard isolated preemies. They were more awake and active. They moved more easily. A year later, on cognitive and motor-skill tests, they looked stronger and smarter than preemies left alone in the standard incubator. Touch therapy is now a routine part of hospital procedures for premature infants.
Field went on to head up the University of Miami’s Touch Research Institute (TRI), where she conducted numerous massage therapy studies. The bottom line in all those studies was that touch is good for your health, your immune system, your sleep, your anxiety level, your life. Eventually, researchers discovered that touch could be an antidote to the painful effects of a still-faced mother; if she gazed blankly but also touched and stroked, the babies seemed to feel connected still. If the mother added touch, her infant would continue to respond, smile, and look back.
Recall Gig Levine’s studies that found a small, interesting break from mother actually improved a baby rat’s life? That effect has been found over and over and since his first surprising—and nearly rejected—research. Researchers have polished, refined, and better explained those inexplicable results. Robert Sapolsky at Stanford and Michael Meaney at McGill University in Montreal expanded on Levine’s original three minutes of handling by increasing it to a fifteen-minute break. Two years later, they could still pick out the handled rats by their capable responses—their smooth easy reactions to a s
trange situation. Their comparison rats—oversheltered and unhandled—were easily startled and prone to rapid increases in corticosterone, a rodent stress hormone comparable to cortisol in humans and other primates.
Corticosterone—and, scientists suspect, cortisol as well—turns out to provoke some chemistry that can actually damage neurons, notably in the hippocampus, where memories are often processed. So handled rats—and, Sapolsky speculated, well-nurtured children—may grow into a healthier adulthood, complete with a brain that stays efficient longer. “Real rats in the real world don’t get handled by graduate students,” Sapolsky notes. “Is there a natural world equivalent?” He and Meaney decided to compare natural mothering styles. Surely, they reasoned, not all rat mothers raise their young with equal attention and care. They were exactly right, of course, and you would find the same thing in humans, monkeys, and just about any other species. “There’s lots of natural variation in mothering,” Meaney says, “from good, to not very good, to very bad.”
By very bad, he doesn’t mean physically abusive. He means unreliable, distracted, neglectful. Even baby rats need a mother who pays attention—licks and cuddles and feeds and protects. What Meaney suspected might be really important was simply what a mother does—or doesn’t do—as part of the everyday routine. So he looked at mothers who focused on their young by devotedly licking and grooming them. He then compared those nurturing females to others who just couldn’t quite stay interested in the little rat pups. Meaney found that the rat pups blessed with mothers who spent a lot of time caring for them had less of that simmering stress chemistry and, therefore, distinctly healthier brains.
In other words, what Sapolsky calls “this grim cascade of stressrelated degeneration” can be slowed, or even stopped, by something as apparently mundane as a mother who pays attention. “It doesn’t have to depart that far from normal to have profound influence on development,” Meaney emphasizes. “You don’t have to beat children, to compromise development.” He did look at childhood stressors beyond the usual variation in mothering. To do that, Meaney turned to a tried and true Harry Harlow technique—isolating baby from mother. In one study, he collaborated with Emory University psychologist Paul Plotsky. They lengthened the separation from mother rat to three hours a day for the first two weeks of their baby rats’ lives. “The most potent effect on stress reactivity that we can achieve is with maternal separation,” Meaney says simply. The two psychologists found that these more severely separated rats grew into chronically stressed adult rodents. Plotsky described them as skittish. They were anxious in new situations. They tended to crouch in one place. “They stick to dark protected places like corners or tunnels,” Plotsky says.