In 1986, in a few of the poorest neighborhoods in Kingston, Jamaica, a team of researchers from the University of the West Indies embarked on an experiment that over the past three decades has done a great deal to demonstrate the potential effectiveness of parent interventions. The experiment involved the families of 129 infants and toddlers who at the beginning of the study showed signs of delay in their development, either physically or mentally. The families were divided into four groups. One group received hour-long home visits once a week from a trained researcher who encouraged the parents to spend more time playing actively with their children: reading picture books, singing songs, playing peekaboo. A second group of children received a kilogram of a milk-based nutritional supplement each week. A third received both the supplement and the play-supporting home visits. And a fourth, a control group, received nothing.
The intervention itself ended after two years, but the researchers have followed the children ever since. (They are now in their early thirties.) The result: the intervention that made a big difference in the children’s lives wasn’t the added nutrition; it was the encouragement to the parents to play. The children whose parents were counseled to play more with them did better, throughout childhood, on tests of IQ, aggressive behavior, and self-control. Today, as adults, they earn an average of 25 percent more per year than the subjects whose parents didn’t receive home visits; by a variety of measures, including wages, these formerly delayed infants have now caught up with a comparison group of their peers who didn’t show any signs of delay in infancy.
The Jamaica experiment makes a strong economic case for the potential effectiveness of some kind of home-visiting intervention with disadvantaged parents. But because the encouragement that the home visitors gave to parents was fairly general, the results don’t necessarily tell us a whole lot about two important questions: Which kind of parental behaviors matter most, and which kind of direction or instruction from home visitors is most likely to incline disadvantaged parents to adopt those behaviors?
There is still considerable uncertainty within the field about the answers to those questions. These days there are three main approaches to home visiting in the United States. Sometimes they compete; sometimes they overlap. One group of interventions primarily targets children’s health; another targets children’s cognition, particularly their vocabulary and reading ability; and a third group targets children’s relationships with their parents.
The most widespread home-visiting program in the country today is one that focuses primarily on health: the Nurse-Family Partnership, which sends trained nurses into the homes of low-income expecting mothers, mostly unmarried teenagers. (There are currently more than 30,000 families enrolled in the program.) The nurses then visit the mothers regularly for the next two and a half years, counseling them about health-promoting behaviors, like quitting smoking, and offering advice on how to keep their children safe and how to get their own lives on track. The Nurse-Family Partnership has been studied in three separate randomized controlled trials, which have shown positive effects on the mothers, including reduced incidence of child abuse, arrest, and welfare enrollment. In most families, there was no significant impact of the home visits on the children’s mental development or school outcomes, but in families where mothers scored especially low on measures of intelligence and mental health, children’s academic performance did improve.
There is less solid evidence behind home-visiting interventions that target children’s literacy and vocabulary skills. These interventions are premised on the real and pressing fact that children’s early exposure to language, both spoken and written, varies widely by class. Well-off kids have on average more access to books and other printed materials; just as important, their parents speak to them more than low-income parents speak to their children—by some estimates, far more—and the speech they use is more complex. These trends correspond, at kindergarten entry, with a significant disadvantage on measures of vocabulary and language comprehension for low-income children.
Given this reality, many researchers and advocates have created experimental programs to try and narrow those gaps by encouraging low-income parents to read and talk more with their children. But it’s hard to find reliable evidence that programs like these result in long-term improvements in the language abilities of disadvantaged children. The challenge is that infants absorb language from parents constantly, not just in dedicated teaching moments. So if you are a parent and you have a limited vocabulary, as many low-income parents do, it’s not easy on your own to nurture in your children a rich vocabulary.
This is part of why many researchers now believe that the most promising approach to parental behavior change may be that third category: interventions that target the relationship between parents and children. Many interventions in this category are aimed at encouraging in children the development of a psychological phenomenon called parental attachment. In the 1950s, researchers in England, Canada, and the United States discovered that when infants experience warm, attentive parenting in the first 12 months of life, they often form a strong, attuned bond with their parents, which the researchers labeled secure attachment. This bond creates in the infants a deep-rooted sense of security and self-confidence—a secure base, in the researchers’ terminology—that enables them to explore the world more independently and boldly as they get older. And that confidence and independence has practical, real-world implications: A landmark longitudinal study of attachment conducted at the University of Minnesota beginning in the 1970s found that infants who at age one showed evidence of secure attachment with their mother went on to be more attentive and engaged in preschool, more curious and resilient in middle school, and significantly more likely to graduate from high school.
Parents who are under a lot of stress, because of poverty or other destabilizing factors in their lives, are less likely than other parents to engage in the kind of calm, attentive, responsive interactions with their infants that promote secure attachment. But what excites many researchers today is the emerging understanding that those behaviors can be learned. It appears to be relatively easy to support and counsel disadvantaged parents in ways that make them much more likely to adopt an attachment-promoting approach to parenting. There’s a chance, in fact, that certain successful parenting interventions promote attachment even when they are not trying to. It may be that part of what produces positive results in health-based interventions like the Nurse-Family Partnership, or read-with-your-kids programs, or even the Jamaican experiment, is that they involve home visitors urging parents to play and read and talk more with their infants—to engage in more serve-and-return moments, in other words—and those up-close parental interactions may have the effect of promoting secure attachment, even if attachment was not the intended target of the intervention.
So does this mean that if we want to promote secure attachment between stressed-out parents and stressed-out infants, the best approach is essentially informational: teaching parents the techniques and behaviors that are most likely to lead to a secure attachment? Can we just hand out some brochures to parents and produce more securely attached infants? Unfortunately, it doesn’t appear to be quite that simple. It’s certainly true that there are specific behaviors that help promote attachment—face-to-face play, a calm voice, serve-and-return interactions, smiles, warm touches. But for many parents, especially those who are living in conditions of adversity or who didn’t receive a lot of attachment-promoting parenting themselves as kids (or both), the main obstacle to that kind of parenting is not that they haven’t memorized the list of approved behaviors. It’s that they are resentful and sleep-deprived and possibly depressed and don’t feel much like serving and returning with the wailing infant in front of them who has a dirty diaper and a bad attitude about nap time. These stressed-out parents need more than just information. And, indeed, the most effective attachment-focused home-visiting interventions offer parents not just parenting tips but psychological and emotional support: The home visitors, through empathy and encouragement, literally make them feel better about their relationship with their infant and more secure in their identity as parents.
When interventions designed to encourage attachment are done right, the effect on disadvantaged parents and their children can be transformative. Another study conducted at the University of Minnesota included 137 families with a documented history of child maltreatment. These were parents, in other words, who had been found to have abused or neglected children in the past and now had a new baby to care for. The families were divided into a control group, which received the standard community services offered to families reported for maltreatment, and a treatment group, which instead received a year of therapeutic counseling focused on the relationship between parents and children. At the end of the year, only 2 percent of the children in the control group were securely attached, while 61 percent of the children in the treatment group were securely attached—a huge difference, and one that had enormous implications for the future happiness and success of those children.