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From Neurons to Neighborhoods: The Science of Early Childhood Development (2000)

Chapter: 14 Conclusions and Recommendations

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Suggested Citation:"14 Conclusions and Recommendations." Institute of Medicine and National Research Council. 2000. From Neurons to Neighborhoods: The Science of Early Childhood Development. Washington, DC: The National Academies Press. doi: 10.17226/9824.
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Suggested Citation:"14 Conclusions and Recommendations." Institute of Medicine and National Research Council. 2000. From Neurons to Neighborhoods: The Science of Early Childhood Development. Washington, DC: The National Academies Press. doi: 10.17226/9824.
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Suggested Citation:"14 Conclusions and Recommendations." Institute of Medicine and National Research Council. 2000. From Neurons to Neighborhoods: The Science of Early Childhood Development. Washington, DC: The National Academies Press. doi: 10.17226/9824.
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Suggested Citation:"14 Conclusions and Recommendations." Institute of Medicine and National Research Council. 2000. From Neurons to Neighborhoods: The Science of Early Childhood Development. Washington, DC: The National Academies Press. doi: 10.17226/9824.
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Suggested Citation:"14 Conclusions and Recommendations." Institute of Medicine and National Research Council. 2000. From Neurons to Neighborhoods: The Science of Early Childhood Development. Washington, DC: The National Academies Press. doi: 10.17226/9824.
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Suggested Citation:"14 Conclusions and Recommendations." Institute of Medicine and National Research Council. 2000. From Neurons to Neighborhoods: The Science of Early Childhood Development. Washington, DC: The National Academies Press. doi: 10.17226/9824.
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Suggested Citation:"14 Conclusions and Recommendations." Institute of Medicine and National Research Council. 2000. From Neurons to Neighborhoods: The Science of Early Childhood Development. Washington, DC: The National Academies Press. doi: 10.17226/9824.
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Suggested Citation:"14 Conclusions and Recommendations." Institute of Medicine and National Research Council. 2000. From Neurons to Neighborhoods: The Science of Early Childhood Development. Washington, DC: The National Academies Press. doi: 10.17226/9824.
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Suggested Citation:"14 Conclusions and Recommendations." Institute of Medicine and National Research Council. 2000. From Neurons to Neighborhoods: The Science of Early Childhood Development. Washington, DC: The National Academies Press. doi: 10.17226/9824.
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Suggested Citation:"14 Conclusions and Recommendations." Institute of Medicine and National Research Council. 2000. From Neurons to Neighborhoods: The Science of Early Childhood Development. Washington, DC: The National Academies Press. doi: 10.17226/9824.
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Suggested Citation:"14 Conclusions and Recommendations." Institute of Medicine and National Research Council. 2000. From Neurons to Neighborhoods: The Science of Early Childhood Development. Washington, DC: The National Academies Press. doi: 10.17226/9824.
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Suggested Citation:"14 Conclusions and Recommendations." Institute of Medicine and National Research Council. 2000. From Neurons to Neighborhoods: The Science of Early Childhood Development. Washington, DC: The National Academies Press. doi: 10.17226/9824.
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Suggested Citation:"14 Conclusions and Recommendations." Institute of Medicine and National Research Council. 2000. From Neurons to Neighborhoods: The Science of Early Childhood Development. Washington, DC: The National Academies Press. doi: 10.17226/9824.
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Suggested Citation:"14 Conclusions and Recommendations." Institute of Medicine and National Research Council. 2000. From Neurons to Neighborhoods: The Science of Early Childhood Development. Washington, DC: The National Academies Press. doi: 10.17226/9824.
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Suggested Citation:"14 Conclusions and Recommendations." Institute of Medicine and National Research Council. 2000. From Neurons to Neighborhoods: The Science of Early Childhood Development. Washington, DC: The National Academies Press. doi: 10.17226/9824.
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Suggested Citation:"14 Conclusions and Recommendations." Institute of Medicine and National Research Council. 2000. From Neurons to Neighborhoods: The Science of Early Childhood Development. Washington, DC: The National Academies Press. doi: 10.17226/9824.
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Suggested Citation:"14 Conclusions and Recommendations." Institute of Medicine and National Research Council. 2000. From Neurons to Neighborhoods: The Science of Early Childhood Development. Washington, DC: The National Academies Press. doi: 10.17226/9824.
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Suggested Citation:"14 Conclusions and Recommendations." Institute of Medicine and National Research Council. 2000. From Neurons to Neighborhoods: The Science of Early Childhood Development. Washington, DC: The National Academies Press. doi: 10.17226/9824.
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Suggested Citation:"14 Conclusions and Recommendations." Institute of Medicine and National Research Council. 2000. From Neurons to Neighborhoods: The Science of Early Childhood Development. Washington, DC: The National Academies Press. doi: 10.17226/9824.
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Suggested Citation:"14 Conclusions and Recommendations." Institute of Medicine and National Research Council. 2000. From Neurons to Neighborhoods: The Science of Early Childhood Development. Washington, DC: The National Academies Press. doi: 10.17226/9824.
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Suggested Citation:"14 Conclusions and Recommendations." Institute of Medicine and National Research Council. 2000. From Neurons to Neighborhoods: The Science of Early Childhood Development. Washington, DC: The National Academies Press. doi: 10.17226/9824.
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Suggested Citation:"14 Conclusions and Recommendations." Institute of Medicine and National Research Council. 2000. From Neurons to Neighborhoods: The Science of Early Childhood Development. Washington, DC: The National Academies Press. doi: 10.17226/9824.
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Suggested Citation:"14 Conclusions and Recommendations." Institute of Medicine and National Research Council. 2000. From Neurons to Neighborhoods: The Science of Early Childhood Development. Washington, DC: The National Academies Press. doi: 10.17226/9824.
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Suggested Citation:"14 Conclusions and Recommendations." Institute of Medicine and National Research Council. 2000. From Neurons to Neighborhoods: The Science of Early Childhood Development. Washington, DC: The National Academies Press. doi: 10.17226/9824.
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Suggested Citation:"14 Conclusions and Recommendations." Institute of Medicine and National Research Council. 2000. From Neurons to Neighborhoods: The Science of Early Childhood Development. Washington, DC: The National Academies Press. doi: 10.17226/9824.
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Suggested Citation:"14 Conclusions and Recommendations." Institute of Medicine and National Research Council. 2000. From Neurons to Neighborhoods: The Science of Early Childhood Development. Washington, DC: The National Academies Press. doi: 10.17226/9824.
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Suggested Citation:"14 Conclusions and Recommendations." Institute of Medicine and National Research Council. 2000. From Neurons to Neighborhoods: The Science of Early Childhood Development. Washington, DC: The National Academies Press. doi: 10.17226/9824.
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Suggested Citation:"14 Conclusions and Recommendations." Institute of Medicine and National Research Council. 2000. From Neurons to Neighborhoods: The Science of Early Childhood Development. Washington, DC: The National Academies Press. doi: 10.17226/9824.
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Suggested Citation:"14 Conclusions and Recommendations." Institute of Medicine and National Research Council. 2000. From Neurons to Neighborhoods: The Science of Early Childhood Development. Washington, DC: The National Academies Press. doi: 10.17226/9824.
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Suggested Citation:"14 Conclusions and Recommendations." Institute of Medicine and National Research Council. 2000. From Neurons to Neighborhoods: The Science of Early Childhood Development. Washington, DC: The National Academies Press. doi: 10.17226/9824.
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Suggested Citation:"14 Conclusions and Recommendations." Institute of Medicine and National Research Council. 2000. From Neurons to Neighborhoods: The Science of Early Childhood Development. Washington, DC: The National Academies Press. doi: 10.17226/9824.
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Suggested Citation:"14 Conclusions and Recommendations." Institute of Medicine and National Research Council. 2000. From Neurons to Neighborhoods: The Science of Early Childhood Development. Washington, DC: The National Academies Press. doi: 10.17226/9824.
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Suggested Citation:"14 Conclusions and Recommendations." Institute of Medicine and National Research Council. 2000. From Neurons to Neighborhoods: The Science of Early Childhood Development. Washington, DC: The National Academies Press. doi: 10.17226/9824.
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Suggested Citation:"14 Conclusions and Recommendations." Institute of Medicine and National Research Council. 2000. From Neurons to Neighborhoods: The Science of Early Childhood Development. Washington, DC: The National Academies Press. doi: 10.17226/9824.
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384 FROM NEURONS TO NEIGHBORHOODS a strong economy; (3) increasing cultural diversity and the persistence of significant racial and ethnic disparities in health and developmental out- comes; (4) growing numbers of young children spending considerable time in child care settings of highly variable quality, starting in infancy; and (5) continuing high levels of serious family problems and adverse community conditions that are detrimental for children. While any given child may be affected by only one or two of these changes, their cumulative impact across the 24 million infants, toddlers, and preschoolers who are now growing up in the United States warrants our dedicated attention and most thoughtful responses. This convergence of advancing knowledge and changing circumstances calls for a fundamental reexamination of the nation’s responses to the needs of young children and their families, many of which were formulated sev- eral decades ago and revised only incrementally since then. It demands that scientists, policy makers, business and community leaders, practitioners, and parents work together to identify and sustain policies that are effective, generate new strategies to replace those that are not achieving their objec- tives, and consider new approaches to address new goals as needed. It is the strong conviction of this committee that the nation has not capitalized sufficiently on the knowledge that has been gained from nearly half a century of considerable public investment in research on children from birth to age 5. In many respects, we have barely begun to use existing science and our growing research capabilities to help children and families negotiate the changing demands and possibilities of life in the 21st century. The fundamental issues addressed by this report concern the relation between early life experiences and early development. Although there have been long-standing debates about how much the early years really matter in the larger scheme of lifelong development, the committee is unequivocal in its conclusion: what happens during the first months and years of life matters a lot. It does not matter because all early damage is irreversible, because missed opportunities can never be made up later, or because the early years provide an indelible blueprint for adult outcomes: early damage may be reversible, some missed opportunities can be made up later, and adult outcomes do not proceed inexorably from early experiences. Rather, the early years of life matter because early damage—whether caused by prenatal injuries or personal rejection—can seriously compromise children’s life prospects. Compensating for missed opportunities, such as the failure to detect early difficulties or the lack of exposure to environments rich in language, often requires extensive intervention, if not heroic efforts, later in life. Early pathways, though far from indelible, establish either a sturdy or fragile stage on which subsequent development is constructed. This chapter presents the committee’s conclusions and recommenda- tions. They are designed to stimulate fresh thinking and promote construc-

CONCLUSIONS AND RECOMMENDATIONS 385 tive public dialogue and action about the most important issues facing the nation’s youngest children and their families. They address two comple- mentary agendas. The first is rooted in contemporary concerns about promoting human capital development in a highly competitive and rapidly changing world. It asks: How can society use knowledge about early child development to maximize the nation’s human capital and ensure the ongo- ing vitality of its democratic institutions? The second is focused on the present and asks: How can the nation use knowledge to nurture, protect, and ensure the health and well-being of all young children as an important objective in its own right, regardless of whether measurable returns can be documented in the future? The first agenda speaks to society’s economic, political, and social interests. The second speaks to its ethical and moral values. The committee is clear in our responsibility to speak to both. POLICY AND PRACTICE State-of-the-art knowledge about early childhood development is mul- tidimensional and cross-disciplinary. It extends from painstaking efforts to understand the evolving circuitry and biochemistry of the immature brain to large-scale investigations of how family characteristics, neighborhood influences, and cultural values affect the well-being of children as they grow up. It includes studies of infants, toddlers, and preschoolers with a broad range of typical and atypical behavioral patterns, as well as young children with diagnosed developmental disabilities. It is derived from a variety of quantitative and qualitative research methods that have been used to under- stand the process of development as it unfolds, as well as from evaluations of efforts to alter its course. Drawing on its extensive review of this highly diverse knowledge base, the committee identified four overarching themes that have guided scien- tific inquiry and have important implications for the design and implemen- tation of the nation’s early childhood policies: (1) all children are born wired for feelings and ready to learn, (2) early environments matter and nurturing relationships are essential, (3) society is changing and the needs of young children are not being addressed, and (4) interactions among early childhood science, policy, and practice are problematic and demand dra- matic rethinking. These four themes provide a framework for our conclu- sions and recommendations to guide policy and practice. The chapter then addresses promising directions for research and evaluation and the chal- lenges of informing the public about the early childhood years, with a particular focus on speaking to the aspirations and concerns of parents of young children.

386 FROM NEURONS TO NEIGHBORHOODS All Children Are Born Wired for Feelings and Ready to Learn From the time of conception to the first day of kindergarten, devel- opment proceeds at a pace exceeding that of any subsequent stage of life. Efforts to understand this process have revealed the myriad and remarkable accomplishment of the early childhood period, as well as the serious prob- lems that confront some young children and their families long before school entry. A fundamental paradox exists and is unavoidable: develop- ment in the early years is both highly robust and highly vulnerable. The committee’s review of research on the achievements and vulnerabilities that characterize the earliest years of life has led to the following conclusions: • From birth to age 5, children rapidly develop foundational capabili- ties on which subsequent development builds. In addition to their remark- able linguistic and cognitive gains, they exhibit dramatic progress in their emotional, social, regulatory, and moral capacities. All of these critical dimensions of early development are intertwined, and each requires focused attention. The early childhood years have value not only as a preparation time for the later accomplishments in school and beyond that have galvanized public attention, but they also have value in their own right as a time of extraordinary growth and change. The developmental tasks of this period range from the mastery of essential building blocks for learning and the motivation to succeed in school, to the ability to get along with other children, to make friends, and become engaged in a social group, as well as the capacity to manage powerful emotions. Although the study of child development has traditionally sorted such accomplishments into discrete functional categories (e.g., cognitive, linguistic, social), in practice they are inseparable beginning in the earliest years of life. Acknowledging and acting on this fundamental principle is critical to the success of a wide array of initiatives in child health, mental health, early education, and early intervention. • Striking disparities in what children know and can do are evident well before they enter kindergarten. These differences are strongly associ- ated with social and economic circumstances, and they are predictive of subsequent academic performance. Redressing these disparities is critical, both for children whose life opportunities are at stake and for a society whose goals demand that children be prepared to begin school, achieve academic success, and ultimately sustain economic independence and en- gage constructively with others as adult citizens. School entry is a critical transition point at which individual differences in what young children know and can do begin to be predictive of longer-

CONCLUSIONS AND RECOMMENDATIONS 387 term patterns of learning and achievement. Marked inequalities in children’s early learning opportunities are therefore a cause for serious concern. In this context, although there has been a proliferation of pre- kindergarten and early intervention initiatives designed to promote school readiness, access to these programs is highly uneven across the early child- hood population in the United States. • Early child development can be seriously compromised by social, regulatory, and emotional impairments. The causes of such impairments are multiple but often revolve around disturbances in close relationships. Indeed, young children are capable of deep and lasting sadness, grief, and disorganization in response to trauma, loss, and early personal rejection. Given the substantial short- and long-term risks that accompany early men- tal health impairments, the incapacity of many early childhood programs to address these concerns and the severe shortage of early childhood profes- sionals with mental health expertise are urgent problems. The mental health of young children has been a relatively neglected topic within the domains of both scientific inquiry and early childhood intervention. Yet debilitating levels of anxiety and emergent conduct disor- ders can be seen in the early years and may have enduring effects on how children view themselves and how they are accepted by others over time. Despite little demonstration of efficacy, extensive pharmacotherapy is be- ing used to treat preschoolers with behavior problems. This is of concern for many reasons, not the least of which is the difficulty in these early years of differentiating children with serious emotional disorders from those who are simply immature or are experiencing transient delays in emotional con- trol. Regardless of the severity of their difficulties, however, children with social or emotional impairments warrant our deepest concern, not only for who they might become as adolescents and adults, but because of their fundamental unhappiness and its consequences for their experiences as young children. Recommendations To support the early learning and social-emotional development of young children, as well as to address the serious mental health needs that can arise during the early years of life, three complementary recommenda- tions require urgent attention. Recommendation 1 — Resources on a par with those focused on lit- eracy and numerical skills should be devoted to translating the knowledge base on young children’s emotional, regulatory, and social development into effective strategies for fostering: (1) the development of curiosity, self-

388 FROM NEURONS TO NEIGHBORHOODS direction, and persistence in learning situations; (2) the ability to cooperate, demonstrate caring, and resolve conflict with peers; and (3) the capacity to experience the enhanced motivation associated with feeling competent and loved. Such strategies and their widespread diffusion into the early child- hood field must encompass young children both with and without special needs. Successful action on this recommendation will require the long- term, collaborative investment of government, professional organizations, private philanthropy, and voluntary associations. Recommendation 2 — School readiness initiatives should be judged not only on the basis of their effectiveness in improving the performance of the children whom they reach, but also on the extent to which they make progress in reducing the significant disparities that are observed at school entry in the skills of young children with differing backgrounds. Recommendation 3 — Substantial new investments should be made to address the nation’s seriously inadequate capacity for addressing young children’s mental health needs. Expanded opportunities for professional training, as recently called for by the Surgeon General, and incentives for individuals with pertinent expertise to work in settings with young chil- dren are essential first steps toward more effective screening, early detec- tion, treatment, and ultimate prevention of serious childhood mental health problems. Early Environments Matter and Nurturing Relationships Are Essential The scientific evidence—ranging from behavioral genetics and neuro- science to policy analysis and intervention research—on the significant de- velopmental impacts of early experiences, caregiving relationships, and en- vironmental threats is incontrovertible. Virtually every aspect of early human development, from the brain’s evolving circuitry to the child’s ca- pacity for empathy, is affected by the environments and experiences that are encountered in a cumulative fashion, beginning early in the prenatal period and extending throughout the early childhood years. The science of early development is also clear about the specific importance of parenting and of regular caregiving relationships more generally. The question today is not whether early experience matters, but rather how early experiences shape individual development and contribute to children’s continued move- ment along positive pathways. Within this context, the committee’s synthe- sis of the pertinent scientific literature has led to the following conclusions: • The long-standing debate about the importance of nature versus nurture, considered as independent influences, is overly simplistic and sci-

CONCLUSIONS AND RECOMMENDATIONS 389 entifically obsolete. Scientists have shifted their focus to take account of the fact that genetic and environmental influences work together in dynamic ways over the course of development. At any time, both are sources of human potential and growth as well as risk and dysfunction. Both geneti- cally determined characteristics and those that are highly affected by expe- rience are open to intervention. The most important questions now con- cern how environments influence the expression of genes and how genetic makeup, combined with children’s previous experiences, affects their ongo- ing interactions with their environments during the early years and beyond. The range of human possibilities is exceedingly broad. At the moment of birth, each baby is neither a preformed individual whose destiny is set, nor a blank slate whose individuality can be shaped entirely by external forces. Children clearly differ in their genetic endowment from the time of conception. Some actively seek out experiences and some are more inhib- ited. Some cry frequently and others are better able to soothe themselves. Some are more predictable and easy to read while others are less easily understood. Biology, however, is modified by life experience. Depending on the caregiving they receive and the environments they encounter, shy children can become sociable, fearful children can become secure explorers of their surroundings, and highly exuberant children can develop consider- able self-control. Each child’s individual capacities are both limited and broadened by his or her genetic makeup and life circumstances. Both operate together in influencing the probability of any given outcome. • Parents and other regular caregivers in children’s lives are “active ingredients” of environmental influence during the early childhood period. Children grow and thrive in the context of close and dependable relation- ships that provide love and nurturance, security, responsive interaction, and encouragement for exploration. Without at least one such relation- ship, development is disrupted and the consequences can be severe and long-lasting. If provided or restored, however, a sensitive caregiving rela- tionship can foster remarkable recovery. Young children establish and can benefit greatly from a variety of close relationships. Yet those adults who are most consistently available and committed to the child’s well-being play a special role in promoting compe- tence and adaptation that cannot be replaced by individuals who are present less consistently or whose emotional commitment is not unconditional. Young children who do not have a relationship with at least one emotion- ally invested, predictably available caregiver—even in the presence of ad- equate physical care and cognitive stimulation—display an array of devel- opmental deficits that may endure over time. Some children develop intense emotional ties to parents and other caregivers who are unresponsive, reject- ing, highly erratic, or frankly abusive. These relationships can also be a

390 FROM NEURONS TO NEIGHBORHOODS source of serious childhood impairments, ranging from problems with fo- cused attention and problem solving to difficulty in forming healthy rela- tionships, failure to thrive, and a variety of serious psychiatric disorders. The remarkable recovery that many such children demonstrate, once they receive responsive and consistent caregiving, provides some of the strongest evidence of the power of these earliest relationships. Indeed, the earlier that children experience supportive and stable caregiving environments, the more likely it will be that they will exhibit healthy development later. • Children’s early development depends on the health and well-being of their parents. Yet the daily experiences of a significant number of young children are burdened by untreated mental health problems in their fami- lies, recurrent exposure to family violence, and the psychological fallout from living in a demoralized and violent neighborhood. Circumstances characterized by multiple, interrelated, and cumulative risk factors impose particularly heavy developmental burdens during early childhood and are the most likely to incur substantial costs to both the individual and society in the future. Extensive research has documented the adverse impacts on young chil- dren of parental mental illness (particularly maternal depression), sub- stance abuse, and recurrent violence. The prevalence of such problems is high, the extent to which they are overlooked is problematic, and the relatively limited availability of specialized expertise to address them re- flects an urgent unmet need. Although these conditions are more common among families living in poverty, they are found in all social classes. More- over, significant dysfunctions frequently cluster together—i.e., maternal depression and substance abuse often go hand in hand; family and commu- nity violence may often affect the same child. These youngsters and their parents are among the most vulnerable members of society, and they re- quire a level of professional expertise that is neither routinely considered in the staffing of conventional early childhood programs nor necessarily avail- able in many high-risk neighborhoods. The short-term financial costs of the professional resources needed to confront these problems are high. The long-term financial and social costs of ignoring serious family disad- vantage or frank pathology, however, are much higher and ultimately contribute to policy failures in other domains, such as education reform, welfare reform, economic and workforce development, and violence pre- vention and crime control. • The time is long overdue for society to recognize the significance of out-of-home relationships for young children, to esteem those who care for them when their parents are not available, and to compensate them ad- equately as a means of supporting stability and quality in those relation-

CONCLUSIONS AND RECOMMENDATIONS 391 ships for all children, regardless of their family’s income and irrespective of their developmental needs. The importance of primary caregiving relationships both within the family and in child care settings during the early childhood years has been documented extensively. For parents and child care providers alike, the experience of caring for a young child is deeply affected by the context in which it is conducted. As both the science of early childhood development and the prevalence of nonparental care have expanded dramatically over the past few decades, the failure to use available knowledge to influence the quality of the nation’s child care is increasingly difficult to understand or to justify. Strategies that are used to recruit and retain talented elementary schoolteachers are no less important for children before they enter school. There is, in particular, an urgent need to upgrade the qualifications and compensation of child care providers. • Early experiences clearly affect the development of the brain. Yet the recent focus on “zero to three” as a critical or particularly sensitive period is highly problematic, not because this isn’t an important period for the developing brain, but simply because the disproportionate attention being given to the period from birth to 3 years begins too late and ends too soon. The mechanisms of neurodevelopment are designed specifically to re- cruit and incorporate a broad spectrum of experience into the developing architecture of the brain. Animal studies make this abundantly clear, and there is no reason to expect that humans, so wonderfully capable of learn- ing and adaptation, are any less sensitive to the effects of experience on brain development. Yet despite a small number of examples, we know remarkably little about the role of experience and the existence (or lack thereof) of time-limited sensitive periods during which specific experiences are obligatory for normal human brain development.. The evidence to either support or refute claims about critical or sensitive periods in humans simply does not exist. It does appear, however, that development of the neural systems supporting cognitive, social, and emotional competencies remains open to experience at least through adolescence. In fact, the brain’s ongoing plasticity enables it to continually resculpt and reshape itself in response to new environmental demands well into adulthood. It is impor- tant to emphasize that these findings do not in any way diminish the impor- tance of the early years. They simply remind us of the continuing impor- tance of the years that follow. • Abundant evidence from the behavioral and the neurobiological sci- ences has documented a wide range of environmental threats to the devel- oping central nervous system. These include poor nutrition, specific infec-

392 FROM NEURONS TO NEIGHBORHOODS tions, environmental toxins, and drug exposures, beginning early in the prenatal period, as well as chronic stress stemming from abuse or neglect throughout the early childhood years and beyond. Decades of research on the early development of the brain convey a powerful and sobering message about its susceptibility to harmful influ- ences. This leads us to be deeply concerned about the well-being of young children who suffer from extreme deprivation, inadequate nutrition, neuro- toxic exposures, or other insults that can cause significant (although some- times subtle) brain damage during the prenatal or early childhood years. Children who are born with auditory, visual, or motor impairments that interfere with the environmental input that their brains receive and children whose caregiving is seriously disrupted in their early years are also highly vulnerable. The greatest dangers arise from the combined and cumulative effects of multiple hazards. What remains to be understood with greater precision are the threshold levels below which adverse environmental ef- fects do not occur, how and why multiple insults operate together to pro- duce additive and sometimes multiplicative effects and, at the other end of the spectrum, how attempts to enhance children’s development affect the developing brain. These questions will be best addressed through sustained scientific collaboration between child development researchers and neuro- scientists. Recommendations To recognize and support the vital significance of the relationships that young children must have with their regular caregivers (parents as well as others) and to prevent the problems that arise from harmful early environ- ments, the committee makes three recommendations that will require sub- stantial shifts in national priorities. Recommendation 4 — Decision makers at all levels of government, as well as leaders from the business community, should ensure that both public and private policies provide parents with viable choices about how to allocate responsibility for child care during the early years of their children’s lives. During infancy, there is a pressing need to strike a better balance between options that support parents to care for their infants at home and those that provide affordable, quality child care that enables them to work or go to school. This calls for expanding coverage of the Family and Medical Leave Act to all working parents, pursuing the com- plex issue of income protection, and lengthening the exemption period before states require parents of infants to work as part of welfare reform. Throughout the early childhood years, policies must accommodate parents’ considerable needs for flexibility and support as they raise young children

CONCLUSIONS AND RECOMMENDATIONS 393 and enhance their opportunities to choose from among a range of child care settings that offer the stable, sensitive, and linguistically rich caregiving that fosters positive early childhood development. Recommendation 5 — Environmental protection, reproductive health services, and early intervention efforts should be substantially expanded to reduce documented risks that arise from harmful prenatal and early postna- tal neurotoxic exposures, as well as from seriously disrupted early relation- ships due to chronic mental health problems, substance abuse, and violence in families. The magnitude of these initiatives should be comparable to the attention and resources that have been dedicated to crime prevention, smok- ing cessation, and the reduction of teen pregnancy. They will require the participation of multiple societal sectors (e.g., private, public, and philan- thropic) and the development of multiple strategies. Recommendation 6 — The major funding sources for child care and early childhood education should set aside a dedicated portion of funds to support initiatives that jointly improve the qualifications and increase the compensation and benefits routinely provided to children’s nonparental caregivers. These initiatives can be built on the successful experience of the U.S. Department of Defense. Society Is Changing and the Needs of Young Children Are Not Being Addressed Developmental science points toward the importance of protecting the multiple environments in which young children live and acknowledging the complexity and significance of the work involved in rearing children both at home and in child care settings. Yet profound social and economic transformations are making it exceedingly difficult for parents to strike a healthy balance between spending time with their children, securing their economic needs, and protecting them from the many risks beyond the home that may have an adverse impact on their health and development. On the basis of its assessment of how the broader contexts within which children develop affect their well-being, the committee drew the following conclu- sions: • Changing parental work patterns are transforming family life. Growing numbers of young children are being raised by working parents whose earnings are inadequate to lift their families out of poverty, whose work entails long and nonstandard hours, and whose economic needs re- quire an early return to work after the birth of a baby. For mothers dependent on public assistance, paid employment and the associated reli-

394 FROM NEURONS TO NEIGHBORHOODS ance on nonmaternal child care are now mandated rather than a matter of choice. The consequences of this changing context of parental employment for young children are likely to hinge on how it affects the parenting they receive and the quality of the caregiving they experience when they are not with their parents. Dramatic changes in what it means to be a working parent with young children, combined with changes in family structure, are having pervasive impacts on how the current generation of children is being raised. More young children than ever before are growing up with single parents who are their family’s sole breadwinner or in two-parent families in which both parents work. The consequence of this dramatic, uncontrolled, natural experiment is a large and growing population of young children who must be cared for by someone other than their parents for a large part of each working day, starting in the first few months of life. In short, the care of infants and young children has been fundamentally reapportioned away from time with parents to extensive hours in nonparental child care set- tings. For many young children, the effects of maternal employment, in particular, appear to be positive. For others, including some young chil- dren of mothers participating in welfare reform, the effects appear to be neutral, although critical opportunities for early intervention are being missed. For yet others, particularly those in early and extensive child care that is of substandard quality, understimulating, and occasionally unsafe, there are serious concerns. • The developmental effects of child care depend on its safety, the opportunities it provides for nurturing and stable relationships, and its provision of linguistically and cognitively rich environments. Yet the child care that is available in the United States today is highly fragmented and characterized by marked variation in quality, ranging from rich, growth- promoting experiences to unstimulating, highly unstable, and sometimes dangerous settings. The burden of poor quality and limited choice rests most heavily on low-income, working families whose financial resources are too high to qualify for subsidies yet too low to afford higher quality care. A baseline standard of quality in the nation’s child care settings is not being met at a time when historic numbers of infants, toddlers, and preschoolers are spending a considerable amount of time in these settings. Notwithstanding substantial increases in federal and state funding for child care in recent years, public expenditures have done little to restructure the inadequate system that existed a decade ago, when the National Research Council last conducted a major review of child care research and called for sweeping policy actions to improve the quality of care in the United States (National Research Council, 1990). Over the intervening years, additional

CONCLUSIONS AND RECOMMENDATIONS 395 research has confirmed the role of quality care in promoting the health and development of young children. The persistence of substandard quality in the nation’s child care arrangements and continuing inequalities in access to quality care thus remains baffling and indefensible. Although some states and localities have taken exemplary steps to upgrade child care quality, significant efforts remain sporadic and uncoordinated. • Young children are the poorest members of society and are more likely to be poor today than they were 25 years ago. Growing up in poverty greatly increases the probability that a child will be exposed to environ- ments and experiences that impose significant burdens on his or her well- being, thereby shifting the odds toward more adverse developmental out- comes. Poverty during the early childhood period may be more damaging than poverty experienced at later ages, particularly with respect to eventual academic attainment. The dual risk of poverty experienced simultaneously in the family and in the surrounding neighborhood, which affects minority children to a much greater extent than other children, increases young children’s vulnerability to adverse consequences. Decades of broad-based economic policies and specific antipoverty ini- tiatives have failed to ensure an adequate income for all families with young children in the United States, including many that are headed by full-time workers. For many children, persistent poverty has become a fact of life, despite a strong economy and much greater work effort by their parents. Work in the absence of sufficient income for a family to escape poverty may do little to facilitate more beneficial child outcomes, especially in the early years of life. This is the emerging message from today’s welfare reform experiments. In light of the negative consequences for young children who experience persistent economic hardship, it is imperative that we develop more effective strategies to promote economic security, as well as acquire a better understanding of those aspects of being poor that are most damaging in order to direct interventions at these potential levers of change. The most suggestive evidence points to specific aspects of parenting and the home environment, namely severe punitiveness, reduced monitoring, in- creased parental psychological distress, and less support for early learning. Recommendations The challenges that arise at the juxtaposition of work, income, and the care of children reflect some of the most complex problems of contempo- rary society. Rather than offer recommendations for specific actions, many of which have been made before and gone unheeded, the committee wishes to underscore the compelling need for a focused, integrative, and compre- hensive reassessment of the nation’s child care and income support policies.

396 FROM NEURONS TO NEIGHBORHOODS Recommendation 7 — The President should establish a joint federal- state-local task force charged with reviewing the entire portfolio of public investments in child care and early education. Its goal should be to develop a blueprint for locally responsive systems of early care and education for the coming decade that will ensure the following priorities: (1) that young children’s needs are met through sustained relationships with qualified caregivers, (2) that the special needs of children with developmental dis- abilities or chronic health conditions are addressed, and (3) that the settings in which children spend their time are safe, stimulating, and compatible with the values and priorities of their families. Recommendation 8 — The President’s Council of Economic Advisers and the Congress should assess the nation’s tax, wage, and income support policies (e.g., the earned income tax credit, minimum wage laws, Tempo- rary Assistance to Needy Families, in-kind supports, and child support policies) with regard to their adequacy in ensuring that no child who is supported by the equivalent of a full-time working adult lives in poverty, and that no family suffers from deep and persistent poverty, regardless of employment status. The product of this effort should be a set of policy alternatives that would move the nation toward achieving these fundamen- tal goals. Interactions Among Early Childhood Science, Policy, and Practice Are Problematic and Demand Dramatic Rethinking Policies and programs aimed at improving the life chances of young children come in many varieties. Some are home based and others are delivered in centers. Some focus on children alone or in groups, and others work primarily with parents. A variety of services have been designed to address the needs of young children whose future prospects are threatened by socioeconomic disadvantages, family disruption, and diagnosed disabili- ties. They range from small-scale model programs, with theoretically guided goals and painstaking attention to implementation, to more generic pro- grams that are implemented widely and often intended to meet a broad array of objectives. They all share a belief that early childhood develop- ment is susceptible to environmental influences and that wise public invest- ments in young children can increase the odds of favorable developmental outcomes. The scientific evidence resoundingly supports these premises. Nevertheless, the committee’s examination of the current obstacles to more constructive cross-fertilization among the domains of science, policy, and practice, has led to the following conclusions: • The overarching question of whether we can intervene successfully

CONCLUSIONS AND RECOMMENDATIONS 397 in young children’s lives has been answered in the affirmative and should be put to rest. However, interventions that work are rarely simple, inexpen- sive, or easy to implement. The critical agenda for early childhood inter- vention is to advance understanding of what it takes to improve the odds of positive outcomes for the nation’s most vulnerable young children and to determine the most cost-effective strategies for achieving well-defined goals. The environmental change required to alter a child’s developmental trajectory is likely to vary for different children in different circumstances. The plasticity of human development works both ways—environments can be both enhancing and debilitating; child change can be for better or worse; and the gains produced by an effective intervention can be maintained by continuing support or lost by the subsequent influences of an impoverished or abusive environment. In the final analysis, all abilities and behaviors unfold within boundaries set by constitutional endowment, and all children (including those with developmental impairments) are primed biologically to seek positive adaptation. Thus, all effective interventions “work” by supporting those self-righting tendencies. Intervention programs are not panaceas—they simply shift the odds in favor of more desirable outcomes. Nevertheless, on both an individual and a population basis, such probabi- listic changes can make a significant difference. This will occur, however, only if the crucial elements of successful strategies are identified and sus- tained as model demonstration programs are transformed into larger-scale implementation. • The scientific knowledge base guiding early childhood policies and programs is seriously constrained by the relatively limited availability of systematic and rigorous evaluations of program implementation; gaps in the documentation of causal relations between specific interventions and specific outcomes and of the underlying mechanisms of change; and infre- quent assessments of program costs and benefits. Recommendations for policy and practice are ideally based on causal evidence. These include, for example, inferences about the effects of early experience on brain development and behavior, the effects of early behavior on later adolescent and adult functioning, and the impacts of specific inter- ventions (such as enhanced child care and early education, home visiting programs, etc.) on child health and development. The committee’s assess- ment suggests that researchers, policy makers, and practitioners often over- estimate the scientific basis for such causal inferences, generally in the service of ensuring continued support for a given policy or practice that is presumed to be effective. Under such circumstances, some observers have drawn sweeping con- clusions from single experiments and have not engaged in a critical exami- nation of the assumptions underlying causal inferences based on nonexperi-

398 FROM NEURONS TO NEIGHBORHOODS mental investigations. In this context, it is important to recognize that strong, generalizable, causal inferences about early childhood development are most often based on the critical evaluation of streams of related re- search rather than on the findings of single studies. Such research streams typically include designs with varied strengths and limitations, yet they provide important convergent evidence that can be assessed in light of the best available theory. Thus, although key policy decisions are often based on evidence that is suggestive rather than conclusive, reasonable inferences based on well-established knowledge and strong evaluation evidence can provide a solid basis for constructive decision making. • Model early childhood programs that deliver carefully designed in- terventions with well-defined objectives and that include well-designed evaluations have been shown to influence the developmental trajectories of children whose life course is threatened by socioeconomic disadvantage, family disruption, and diagnosed disabilities. Programs that combine child- focused educational activities with explicit attention to parent-child inter- action patterns and relationship building appear to have the greatest im- pacts. In contrast, services that are based on generic family support, often without a clear delineation of intervention strategies matched directly to measurable objectives, and that are funded by more modest budgets, ap- pear to be less effective. The ultimate answers to questions about program effectiveness are unlikely to be found solely in the particular service format or strategy that is deployed, such as a home visiting model, a comprehensive center-based program, an antipoverty initiative, or a substance abuse treatment or men- tal health service. Rather, the key to success is more likely to be found in the quality of program implementation, which frequently is related to the level of available resources. This directs attention to a host of important factors, such as: (1) the program’s relevance, sensitivity to, and respect for the individual needs and cultural values of the children, families, and com- munity it is designed to serve (which, in turn, affect recruitment and reten- tion of the children and families it is designed to reach); (2) the program’s intensity and duration; and (3) staff competence and the training support and compensation that are provided to them. It also is essential to ac- knowledge that the possibilities for change are not infinite, and that some programs may achieve only modest goals at considerable cost. In the final analysis, an intervention program is simply one of many influences on a child’s health and development. In some circumstances, its impact can be considerable; in others, its potential effects may be overwhelmed by forces beyond its control. • The elements of early intervention programs that enhance social and

CONCLUSIONS AND RECOMMENDATIONS 399 emotional development are just as important as the components that en- hance linguistic and cognitive competence. Some of the strongest long-term impacts of successful interventions have been documented in the domains of social adjustment, such as reductions in criminal behavior. The assessment of social-emotional development in the first five years of life is complex, time-consuming, and generally not part of the standard repertoire of outcomes that are measured in many evaluations of early childhood programs. Yet these realms of development contain some of the most telling indicators of the success or failure of an intervention. To the extent that the early childhood intervention community seeks to draw on emerging research on brain development to support its efforts, it is impor- tant to recognize that selected aspects of regulatory behaviors and social interaction have become an important focus in the neurosciences. • The reconciliation of traditional early intervention programs, for- mats, and strategies—many of which emphasize the importance of active parent involvement and the delivery of services in the home setting—with the economic and social realities of contemporary family life is a pressing concern. Particularly urgent is the need to ensure access to these interven- tion programs for parents who are employed full-time, those who work nonstandard hours, and those who are making the transition from public assistance to work. Recent social and economic changes present major challenges to con- ventional early childhood interventions and service models that were de- signed over 30 years ago, when mothers were more commonly at home full- time with their young children. Central to the philosophy of many of these programs is the importance of regularly scheduled home visits and exten- sive parent involvement in out-of-home settings and activities. These re- quirements are increasingly difficult for many parents to meet, particularly for those working in full-time low-wage jobs. At a minimum, this situation calls for a significant restructuring of program practices in order to enhance their compatibility with parents’ work schedules. In a broader context, it calls for innovative approaches that reflect creative rethinking of the con- cept of family-centered services. • Early childhood policies and practices are highly fragmented, with complex and confusing points of entry that are particularly problematic for underserved segments of the population and those with special needs. This lack of an integrative early childhood infrastructure makes it difficult to advance prevention-oriented initiatives for all children and to coordinate services for those with complex problems. Conventional approaches to the promotion of child health and devel- opment begin with a call for universal access to comprehensive prenatal

400 FROM NEURONS TO NEIGHBORHOODS care for all pregnant women and a “medical home” to provide primary health care services for all children. To this end, efforts to expand Medic- aid eligibility for prenatal care for low-income women and the current federal-state program to provide health insurance for low-income children (State Children’s Health Insurance Program under Title XXI of the Social Security Act) are vital public initiatives. Beyond the matter of insurance coverage, the content of pediatric primary care is also receiving attention through new initiatives that underscore the time-intensive need for relation- ship building among health care providers, parents, children, and a range of professionals who provide developmental and social services through non- medical programs. Central to an effective strategy to protect and promote the healthy development of young children is the need to both understand the impor- tant role of the personal health care system and recognize its significant limitations. This is particularly salient with respect to two critical chal- lenges. First, many of the well-documented risk factors that can impair early brain development are embedded in the experiences of poverty, mal- nutrition, illiteracy, violence, toxic exposures, and substance abuse and other risk-taking behaviors. These threats to child health and development call for a strengthened prevention agenda that extends beyond the capacity of individually oriented medical care and requires a more vigorous and creative public health approach. Second, much of the expertise needed to address the needs of children with significant developmental and behavioral impairments is located in separate programs that are provided under the administrative and financial auspices of a variety of agencies (e.g., educa- tion, social or human services, child welfare). When communication and coordination among multiple systems is good, the needs of children and families are served. When it is poor, resources are not used efficiently and important needs are not met adequately. Developmentally vulnerable chil- dren who live in highly stressed environments, particularly where there are concerns about possible abuse and neglect, warrant special concern. • The growing racial, ethnic, linguistic, and cultural diversity of the early childhood population requires that all early childhood programs and medical services periodically reassess their appropriateness and effective- ness for the wide variety of families they are mandated to serve. Poor “take-up” and high rates of program attrition that are common to many early intervention programs, while not at all restricted to specific racial, ethnic, or linguistic groups, nonetheless raise serious questions about whether those who design, implement, and staff early childhood programs fully understand the meaning of cultural competence in the delivery of health and human services.

CONCLUSIONS AND RECOMMENDATIONS 401 Traditional program formats and strategies (both for children who are labeled at risk and for those with diagnosed disabilities) need to be recon- ciled with the values and cultural practices of an increasingly diverse popu- lation. For many families, including both immigrant and native-born fami- lies with widely varying cultural and linguistic backgrounds, involvement in an early intervention program can be a complex challenge. The potential complications may include different perceptions of: (1) parenting roles and functions, (2) expectations of young children and beliefs about appropriate developmental goals, (3) views about needing and accepting “help” from nonfamily members, (4) fears about being judged unfavorably, and (5) barriers imposed by language. Although major strides have been made in adapting traditional service formats to the needs and beliefs of an increas- ingly diverse array of families, such as those achieved by Head Start, the design of interventions that are perceived as relevant, engaging, and needed by the full spectrum of targeted families remains a central challenge to the field. If this challenge is not addressed, rates of program nonacceptance and attrition are likely to remain high and program effectiveness will be compromised. • The general political environment in which research questions are formulated and investigations are conducted has resulted in a highly prob- lematic context for early childhood policy and practice. In many circum- stances, the evaluation of intervention impacts is largely a high-stakes activ- ity to determine whether policies and programs should receive continued funding, rather than a more constructive process of continuous knowledge generation and quality improvement. In view of the fact that responsible early childhood policy and practice typically require sound judgment in the face of incomplete information, the risks associated with alternative courses of action must always be weighed in light of the uncertainty about the strength of the available evidence. When research is used both to confirm effectiveness (in order to sustain successful programs) and to identify ineffectiveness (in order to abandon failed strategies and inform the design of alternative approaches), the inter- ests of children are well served. However, when the purpose of research is simply to mobilize data to secure support for a specific program (or to terminate it), independent of its merits, the interests of children are thwarted, the field fails to move forward, and society pays a high price. As with the treatment of disease, the management of developmental vulner- ability in young children should be driven not by a question of whether successful intervention is a worthy goal, but by a determination to continu- ously harness science in an effort to enhance the capacity to promote hu- man health and well-being.

402 FROM NEURONS TO NEIGHBORHOODS • As the rapidly evolving science of early child development continues to grow, its complexity will increase and the distance between the working knowledge of service providers and the cutting edge of the science will be staggering. The professional challenges that this raises for the early childhood field are formidable. They range from relatively straightforward issues, such as curriculum content, to more fundamental questions about professional iden- tification, career pathways, cross-disciplinary collaboration, the potential indications for new disciplines, the need for a culturally diverse workforce, and the critical issue of professional compensation. Recommendations To enhance the capacity of early childhood programs to address serious threats to early development and to ensure that practitioners and policy makers can learn from previous efforts to intervene in the lives of young children, three recommendations demand attention: Recommendation 9 — Agencies and foundations that support evalua- tion research in early childhood should follow the example set by the nation’s successful approach to clinical investigation in the biomedical sci- ences. In this spirit, the goals of program-based research and the evaluation of services should be to document and ensure full implementation of effec- tive interventions, and to use evidence of ineffectiveness to stimulate further experimentation and study. Recommendation 10 — The time is long overdue for state and local decision makers to take bold actions to design and implement coordinated, functionally effective infrastructures to reduce the long-standing fragmen- tation of early childhood policies and programs. To this end, the commit- tee urges two compelling first steps. First, require that all children who are referred to a protective services agency for evaluation of suspected abuse or neglect be automatically referred for a developmental-behavioral screening under Part C of the Individuals with Disabilities Education Act. Second, establish explicit and effective linkages among agencies that currently are charged with implementing the work requirements of welfare reform and those that oversee the provision of both early intervention programs and child and adult mental health services. Recommendation 11 — A comprehensive analysis of the professional development challenges facing the early childhood field should be consid- ered as a collaborative effort involving professional organizations and rep- resentatives from the wide array of training institutions that prepare indi-

CONCLUSIONS AND RECOMMENDATIONS 403 viduals to work with young children and their families. The responsibility for convening such a broad-based working group or commission should be shared among the fields of education, health, and human services. RESEARCH AND EVALUATION Research has historically played a significant role in enhancing human development and preventing, ameliorating, and treating a range of condi- tions that can begin prenatally, at birth, or during the early years of life. To identify priorities among the many possible recommendations that could be made for promising future research, the committee was guided by three goals. First, it is clear that the capacity to increase the odds of favorable birth outcomes and positive adaptation in the early childhood years would be strengthened considerably by the new knowledge that would be generated by enhanced collaboration among child development researchers, neurosci- entists, and molecular geneticists. A creative combination of biological and psychosocial research efforts would increase the ability to unlock some of the enduring mysteries about how biogenetic and environmental factors interact in a reciprocal fashion to influence developmental pathways. To accomplish this, the great divide that currently exists among these groups of researchers must be closed through the support of novel collaborations. Second, there is a pressing need to integrate basic research aimed at understanding developmental processes with intervention research that as- sesses efforts to influence developmental outcomes. At present, evidence from the basic sciences about factors that shift developmental trajectories toward adaptive or maladaptive outcomes is, at best, haphazardly trans- lated into the design and evaluation of initiatives aimed at changing these trajectories. Similarly, those who study interventions lack systematic op- portunities to feed their insights and questions back into the basic research enterprise. Comprehensive research programs that integrate efforts to un- derstand development with efforts to change it are even more unusual. There are, however, some pioneering examples (e.g., Cowan and Cowan, in press; Dishion et al., 1992; Egeland et al., 2000; Olds et al., 1999) whose experiences can pave the way for greater efforts in the future. Third, the entire early childhood evaluation enterprise warrants a thor- ough reassessment in order to maximize opportunities for valid causal inference and generalization, to assess what has been learned cumulatively across the full array of evaluation studies, and to establish a constructive environment for the discussion of ongoing research and its application to policy. With these goals as a guide, the committee makes the following recom- mendations for a three-pronged agenda for research and evaluation.

404 FROM NEURONS TO NEIGHBORHOODS Integrating Child Developmental Research, Neuroscience, and Molecular Genetics The committee recommends that funds be earmarked for collaborative projects involving researchers who investigate environmental influences on development and those who study the biological bases of behavior, in order to advance the understanding of: • How experience is incorporated into the developing nervous system and how the boundaries are determined that differentiate deprivation from sufficiency and sufficiency from enrichment for different children who are reared in a wide variety of environments. Notwithstanding the current fascination with the relation between early experience and early brain development, there is very little research on how early environments specifically affect the rapidly developing central ner- vous system of the young child. Moreover, there are only a handful of investigators who have the skills needed to assess the effects of early inter- ventions designed both to promote positive developmental outcomes and to remediate developmental impairments (including early sensorimotor diffi- culties) on various indicators of neurologic functioning. This area of poten- tial investigation offers one of the few available avenues for addressing questions about thresholds of experience below which damage may occur and above which development may be enhanced. • How biological processes, including neurochemical and neuroendo- crine factors, interact with environmental influences to affect the develop- ment of complex behaviors, including self-regulatory capacities, prosocial or antisocial tendencies, planning and sustained attention, and adaptive responses to stress. There is growing agreement among both scientists and clinicians that the underlying roots of attention problems, learning difficulties, and con- duct disorders can be found in the (currently) poorly understood interac- tions between biological vulnerabilities and environmental demands. Fur- ther research in this area will advance both the development of effective interventions for improving the lives of children with impairments and a greater understanding of behavioral development in young children who are relatively free of problems. Research that extends evidence from animal models to expand understanding of how detrimental early experiences af- fect the regulation of the fear-stress system in human infants and young children will be particularly important. • The dynamics of gene-environment interactions that underlie the development of behavior and contribute to differential susceptibility to risk and capacity for resilience.

CONCLUSIONS AND RECOMMENDATIONS 405 The growing appreciation of large individual differences in susceptibil- ity to environmental risks has galvanized the interest of both behavioral scientists and geneticists, yet researchers trained in these two empirical traditions continue to work largely along parallel tracks. Collaborative endeavors between these two groups, including those that address the com- plex methodological challenges in this field, could more fruitfully explore such significant concerns as: (1) differential birth outcomes associated with exposure to prenatal hazards (e.g., malnutrition, infection, and drug expo- sure), (2) the emergence of adverse outcomes (ranging from conduct disor- ders to frank pathology) in some children but not others in response to stressful rearing conditions, and (3) individual differences in susceptibility to diseases that manifest themselves across the full spectrum of the develop- mental timeline. • The mechanisms that underlie nonoptimal birth outcomes and de- velopmental disabilities and their implications for developing specific inter- vention strategies to modify developmental trajectories. The increasingly sophisticated tools of molecular genetics and neurobi- ology, combined with technologies that are enhancing the capacity to study a wide variety of behaviors in young children, offer the potential for impor- tant insights into the processes that lead to a range of developmental vul- nerabilities and diagnosed disabilities. Furthermore, while substantial progress has been made in preventing infant deaths associated with low birthweight and prematurity, society is still relatively unprepared to address the learning and behavioral problems that many of these infants exhibit as they grow up. Integrating the Basic Science of Human Development and the Applied Science of Early Childhood Intervention In an effort to promote greater cross-fertilization between those who study the underlying science of early development and those who evaluate the efficacy of interventions, the committee recommends that high priority be assigned to the following lines of inquiry: • Research on early pathways toward psychopathology, which brings together those who study social-emotional development from a variety of disciplines (e.g., infant mental health, developmental psychology, social work, genetics, neuroscience, pediatrics, and psychiatry) and those involved in the design and implementation of both preventive and therapeutic inter- ventions. Several important research programs are investigating precursors to later antisocial behavior and anxiety-related pathology among constella-

406 FROM NEURONS TO NEIGHBORHOODS tions of temperamental and genetic vulnerability, dysfunctional parenting, and stressful or disorganized early environments that are found in the preschool years. Many of these empirical associations are now sufficiently consistent to warrant a solid investment in programmatic longitudinal stud- ies designed to: (1) elucidate pathways toward psychopathology and iden- tify factors that leave some children at continuing risk while steering others toward adaptive outcomes, (2) distinguish early clinical patterns that are indicative of serious emergent disorders from those that reflect transient concerns, and (3) support efforts to translate the findings from such re- search into (initially) small-scale interventions in a range of settings. To this end, the development of interventions geared to preschool classrooms offers a particularly promising avenue for advancing the early detection and prevention of problems that become apparent when children first encounter peer groups, with their associated demands for compliance with group norms. • Research that integrates investigations focused on how early biologi- cal insults, (e.g., iron deficiency anemia, lead ingestion) and adverse envi- ronmental conditions (e.g., chronic stress) interfere with healthy prenatal and postnatal development, with efforts to design both preventive and ameliorative interventions for women and children who are exposed to such threats, as well as for children with identified disabilities. A central objective of such integrative research is the exploration of interactions among biological vulnerability, environmental risk, and effec- tive interventions. Previous investigations of this type have stimulated the development of a number of beneficial policies and programs, such as the Women, Infants, and Children (WIC) nutrition support program to prevent iron deficiency anemia and state initiatives to eliminate lead in gas and house paint to prevent lead intoxication. The important issues that such research could address include: (1) the timing and duration of effects, for both exposures and interventions; (2) the capacity for recovery and what it takes to produce improved outcomes; (3) factors that contribute to indi- vidual differences in outcomes; and (4) pathways from diverse deleterious experiences to common neurobehavioral outcomes. • Studies that elucidate the causal pathways through which impover- ished family resources contribute to adverse outcomes for individual chil- dren and persistent disparities across groups of children in learning skills and other developmental outcomes. The committee reached strong agreement that there is little scientific merit in additional research that simply reconfirms the association between poverty and poor developmental outcomes. Furthermore, new evidence from studies of welfare reform underscores the urgent need for a new

CONCLUSIONS AND RECOMMENDATIONS 407 generation of research aimed at understanding: (1) the modifiable mecha- nisms through which financial hardship and economic insecurity affect parenting behaviors, the emotional climate of the home, and parent mental health which, in turn, affect children’s well-being; (2) the levels of earned income and features of work that are associated with improved outcomes for children and the processes that account for observed relations among income, work, and child development; and (3) differing patterns of associa- tion and causality between children’s circumstances and their well-being for children and families at varying initial levels of risk as defined by socioeco- nomic conditions, parent and child well-being, (health and developmental status), neighborhood conditions, and cultural factors. • Experimental investigations of the developmental effects of varia- tions in child care quality, extending from center-based early intervention programs, which have been the focus of previous program evaluations, through the broader range of child care and early education programs available, which have rarely been assessed with experimental designs. Although there is firm, experimental evidence that high-quality, com- prehensive, center-based early intervention programs can shift the odds in favor of more positive short- and long-term developmental outcomes for young children, and thereby produce a handsome social return on their investments, we lack comparable causal evidence on the developmental consequences of more typical child care arrangements, only some of which are center-based. Given the unlikely possibility that sufficient investments will ever be made to ensure access for all low-income children to programs that approach the magnitude and scope of the High/Scope Perry Preschool or Abecedarian projects, for example, policy makers need credible informa- tion about the potential impacts of lesser investments in program quality. • New research and secondary data analyses that integrate studies of parenting with evaluations of parenting interventions in order to advance understanding of what it takes to change parenting practices and what magnitude of change is required to produce positive (and enduring) changes in child developmental outcomes in a wide range of circumstances, both inside and outside the home. The inconsistent and uneven evaluation literature on parenting inter- ventions is a serious deterrent to sound policy making at a time when many governors and state legislators are proposing greater investments in such early childhood initiatives. At this stage in the maturation of the field, there is little justification for additional correlational studies of home visiting or parent education programs. Alternatively, there is a compelling need for rigorous evaluations that examine causal links between parenting interven- tions and specific parent (or parenting) outcomes and that assess mediated

408 FROM NEURONS TO NEIGHBORHOODS pathways from treatment effects on the parent to developmental impacts on the child. At the same time, there are some very promising examples of parenting interventions that have been guided by basic research on parent influences and behavior change. These studies are contributing to growing understanding of the relative plasticity of parenting and the dimensions that matter most for children growing up in different circumstances. The chal- lenge is to extend these models of theory-based, causal assessments of parenting programs to broader scale interventions. • Research that draws on the significant theoretical work and practi- cal guidelines that have been developed regarding culturally competent practice, in order to refine this construct empirically and assess the benefits that are gained from its incorporation into training models, policy develop- ment, service strategies, and program evaluations. The growing ethnic, racial, and linguistic diversity of the early child- hood population in the United States confronts service providers (who are a relatively homogenous population) with the complex task of considering when to tailor their efforts to specific populations of children and families and when to treat all families similarly. Currently, however, there is little empirical research to inform this pressing issue. Studies that integrate qualitative and quantitative methods are especially well suited to address the fundamental questions in this area. • Efforts to undertake the laborious, but vitally needed, task of im- proving the available tools for measuring important but generally neglected early developmental outcomes (i.e., before school entry) for use in both basic and evaluation research. Leading candidates for this work include measures of the multiple components of self-regulation, emotional develop- ment, the capacity to make friends and engage with others as a contributing member of a group, language use (as distinct from static measures of vo- cabulary), and executive functions, such as working memory. Notwithstanding the continuing emphasis on standardized cognitive evaluation and the persistent popularity of IQ scores in the policy arena, a lesson from the early intervention literature is that these assessments may not be very sensitive to the behaviorally meaningful effects of a program. The developmental sciences offer a richer array of assessment options. In the absence of dedicated attention to this agenda, multiple opportunities for detecting important intervention effects will continue to be missed. Several challenges are central to this work. First, there is an urgent need to adapt instruments that are already available for use in intervention studies. Second, a balance of attention needs to be given to matters related to internal and external validity. Third, it is essential that this work not only ensure that validation samples include children from diverse cultural

CONCLUSIONS AND RECOMMENDATIONS 409 backgrounds, but also that it explicitly consider how competencies are most appropriately assessed in different cultural groups and how each instru- ment functions as part of a constellation of outcome measures for children with different backgrounds. Fourth, the development of instruments that could contribute to the integration of research on typically and atypically developing children would be a significant advance for developmental sci- ence. Finally, the compelling need and considerable costs of such an under- taking underscore the importance of public-sector leadership. Improving Evaluations of Early Childhood Interventions In an effort to improve the nation’s capacity to learn more from evalu- ations of early childhood interventions, the committee recommends that: • Much greater attention be paid to the challenges of program imple- mentation, using both qualitative and quantitative research methods, as an integral component of all early childhood evaluation research. To this end, it is essential that funding for evaluations of intervention services build in support for the time-consuming and ongoing assessment of the range of factors that are tied to effective implementation. Inattention to implementation issues can undermine the utility of pro- gram evaluations aimed at causal questions and seriously compromise the interpretation of study findings. These issues include concerns about (1) program take-up and differential engagement by different targeted popula- tions, (2) goodness of fit between program objectives and strategies and the needs and values of the families who are being served, (3) how the broader community responds to the intervention, (4) the skill and stability of pro- gram staff, and (5) the nature of the transactions that occur between the staff delivering the intervention and the individuals receiving it. Implemen- tation is also a moving target that can change, sometimes dramatically, over the course of an intervention, making it a more complex and challenging endeavor than is commonly acknowledged. • Funding agencies adopt higher standards and demand rigorous and appropriate study designs that: (1) draw explicit links between the theory guiding the program and the assessment of program effects, (2) maximize opportunities for making causal connections between intervention and out- comes through the use of experimental designs whenever feasible and well- designed quasi-experimental studies when necessary, (3) add to the field’s understanding of the mechanisms involved in successful change efforts, and (4) assess the cost-effectiveness of alternative courses of action. The development of effective early intervention strategies hinges on the validity of the reasoning that underlies the program’s goals and design, the

410 FROM NEURONS TO NEIGHBORHOODS adequacy and fidelity of its implementation, and the availability of reliable information about the extent to which the program meets its objectives given its costs. Too often, these elements are poorly conceptualized or seriously compromised as a result of tight budgets, inadequate expertise, a rush to evaluate, or other related pressures. Funding agencies can play an instrumental role in upgrading the quality of the early childhood evaluation enterprise by addressing these concerns in both the selection of their grant recipients and the monitoring of funded projects. A high priority should be placed on research programs that move from efficacy trials (which test an intervention under optimal conditions) to effectiveness studies (which test the intervention under more typical conditions, as when the program is conducted on a larger scale) to dissemination studies (which examine the degree to which the program is conducted with fidelity to the model, once it has been exported to new communities and administered as a service rather than as an experimental intervention) (see Olds et al., 1999). • The National Institutes of Health, in conjunction with appropriate programmatic agencies and private foundations, convene regular forums to synthesize evaluation research evidence across programs and strategies that share similar developmental aims. There is an urgent need for more rigorous synthesis of streams of related intervention research across the multiple domains of early child- hood services in order to investigate causal questions and assess the generalizability of findings. Consensus conferences convened by the Na- tional Institutes of Health provide a highly regarded mechanism for evalu- ating available scientific information and assessing its practical implica- tions. These meetings afford a vehicle for moving beyond the piecemeal presentation of evidence from diverse bodies of literature and for ensuring the unbiased synthesis of findings that can inform broader discussions of effective strategies, in contrast to “up or down” appraisals of individual programs. Among the topics that such conferences could address are: (1) the relative costs and benefits of early interventions that are directed primarily at parents (and only indirectly at children) in comparison to those that provide services directly to children, or combine both approaches in a two-generation strategy; (2) the importance of timing, duration, and inten- sity of services, in addition to the qualifications, training, and supervision of staff, as significant determinants of their effectiveness; and (3) the issues discussed above regarding program implementation. • The universe of programs that typically are assessed with regard to their impacts on early childhood development be expanded beyond the traditional child- and family-focused models to encompass broad-based economic and community interventions as well.

CONCLUSIONS AND RECOMMENDATIONS 411 Despite growing awareness of the vulnerabilities and opportunities that characterize the early childhood years, several promising social and economic interventions and their evaluations have failed to include early childhood outcomes within their assessment protocols. Evaluations of the Moving to Opportunity neighborhood experiment and a number of state- designed welfare-to-work experiments are examples of such lost opportuni- ties. These and other interventions that have not been designed explicitly to enhance child well-being may nevertheless have significant impacts on chil- dren. The committee therefore urges those who fund and design evalua- tions of broad-based social interventions, ranging from economic develop- ment strategies to housing and transportation initiatives, to consider the value of including assessments of early (and later) childhood outcomes. THE CHALLENGE OF EDUCATING THE PUBLIC New scientific information relevant to the health and development of children is always of interest to the general public. Parents of very young children are particularly eager for authoritative guidance, and this insa- tiable thirst provides a highly receptive environment for both responsible education and irresponsible manipulation. Within this context, research- based knowledge can be both informative and useful, but the reality of childrearing is always more of an art than a science. Helping the public to understand the science of early childhood devel- opment is not an easy task. This challenge can be facilitated by differenti- ating among established knowledge, reasonable hypotheses, and unwar- ranted assertions. Established knowledge (e.g., the important influence of the infant-caregiver relationship on early cognitive and emotional develop- ment) is determined by strict rules of evidence and evolves continuously. Reasonable but untested hypotheses (e.g., repeated exposure to violence alters neural circuits in the developing brain that control an infant’s reac- tion to threat) make up a large proportion of the knowledge base that guides responsible policy, service delivery, and parenting practices at any point in time, but they may be confirmed or disproved by subsequent investigation. Unwarranted assertions in the name of science (e.g., access to expensive educational toys will boost infant intelligence) distort or misrep- resent knowledge, undermine its credibility, and are most insidious when put forth by individuals with professional credentials. In a curiously parallel fashion, successful parenting, effective service delivery, and informed policy making may all very well be defined as the ability to make reasonable judgments and avoid irresponsible practices in the face of incomplete knowledge. Ultimately, each must reconcile the neverending quest for more information with a comfortable level of toler- ance for the unavoidable ambiguity and essential mystery of human devel-

412 FROM NEURONS TO NEIGHBORHOODS opment. In this context, an educated public would be better informed about early childhood development by a clear understanding of state-of- the-art concepts and expectations than by the rote memorization of age- specific milestones and highly prescriptive advice. To this end, the commit- tee presents the following scientific conclusions: • The development of the brain begins before birth, continues through- out life, and is influenced by both genetics (i.e., what one is born with) and experience (i.e., the kind of environment in which one lives). • All behavior and development reflect brain function, but currently there are very few scientific data that link specific experiences at specific times with specific effects on the developing central nervous system. More- over, more is known about the adverse impacts of deprivation than the beneficial effects of enrichment, and most of the knowledge about brain development comes from studies of adults and animals other than humans. • The astonishing developmental achievements of the earliest years occur naturally when parents and other caregivers talk, read, and play with young children and respond sensitively to their cues. There are no special programs or materials that are guaranteed to accelerate early learning dur- ing infancy. • Nurturing, stable, and consistent relationships are the key to healthy growth, development, and learning, and there are many ways to be a suc- cessful parent. The best enrichment comes from loving interactions with people who provide a rich variety of opportunities for exploration and discovery. • The early years of life are an important time of active development, foundation building, and clear periods of reorganization. There is, how- ever, no sharp break at age 3 (or 5), and there is no scientific reason to believe that the behavioral consequences of negative early experiences can- not be ameliorated by interventions initiated in later childhood, or that positive early experiences provide permanent protection against later ad- versity. • There are many variations along the road to competence, and a wide range of individual differences among normally developing children can present quite formidable challenges to parents and other caregivers along the way. Notwithstanding the inevitable bumps in the road, the course of human development, like that of all living organisms, moves naturally in the direction of positive adaptation. • The developing brain is dependent on the inputs of a variety of early sensory, perceptual, and motor experiences (e.g., sound, binocular vision, movement through space) that are easily met, unless a child is born with an auditory, visual, or motor deficit that interferes with the expected input.

CONCLUSIONS AND RECOMMENDATIONS 413 The early detection and remediation of such problems are essential compo- nents of primary health care. • Efforts to protect early brain development are best embedded in an overall strategy of general health promotion and disease prevention. This includes attention to the importance of adequate nutrition (beginning dur- ing the prenatal period), the avoidance of harmful exposures (e.g., drugs, viruses, and environmental toxins), and protection from the stresses of chronic understimulation or significant maltreatment (i.e., abuse or ne- glect). • There is considerable variability among childrearing environments that promote healthy development, much of which is embedded in different values and cultural practices that are passed on from one generation to the next and are continually transformed by each generation based on the times in which it lives. • Well-described deviations that exist in all cultures (e.g., extreme and persistent poverty, serious parental psychopathology, family violence) can be extremely damaging to all children. Specific threats to development can originate from within the child or the environment, but significant vulner- ability results less from a single source and more from the cumulative burden of multiple risk factors. Within this context, the boundaries among normative variations, transient maturational differences, and persistent dis- abilities are often blurred and difficult to define in the early childhood period. The combined impact of both biological and environmental risk presents the greatest threat. • The early detection of problems and the prompt provision of an appropriate intervention can improve developmental outcomes (i.e., shift the odds) for both children living in high-risk environments and children with biologically based disabilities. However, not all interventions are effective, when they do work they are rarely panaceas, and (unlike immuni- zations followed by an occasional booster) they do not confer a lifetime of protection. In summary, the well-being and “well-becoming” of young children are dependent on two essential conditions. First is the need for stable and loving relationships with a limited number of adults who provide respon- sive and reciprocal interaction, protection from harm, encouragement for exploration and learning, and transmission of cultural values. Second is the need for a safe and predictable environment that provides a range of growth- promoting experiences to promote cognitive, linguistic, social, emotional, and moral development. The majority of children in the United States today enjoy the benefits of both. A significant number do not.

414 FROM NEURONS TO NEIGHBORHOODS CONCLUDING THOUGHTS As this report moved to completion, it became increasingly clear to the members of the committee that the science of early childhood development has been viewed through highly personalized and sharply politicized lenses. In many respects, this is an area in which personal experience allows every- one to claim some level of expertise. Moreover, as a public issue, questions about the care and protection of children confront many of the basic values that have defined this country from its founding—personal responsibility, individual self-reliance, and restrained government involvement in people’s lives. In a highly pluralistic society that is experiencing dramatic economic and social change, however, the development of children must be viewed as a matter of intense concern for both their parents and for the nation as a whole. In this context, and based on the evidence gleaned from a rich and rapidly growing science base, we feel an urgent need to call for a new national dialogue focused on rethinking the meaning of both shared re- sponsibility for children and strategic investment in their future. The time has come to stop blaming parents, communities, business, and government—and to shape a shared agenda to ensure both a rewarding childhood and a promising future for all children. Central to this agenda is the importance of matching needs and capabilities. Families, for example, are the best vehicle for providing loving and caring relationships and for creating safe and nurturing environments that promote healthy physical, cognitive, linguistic, social, emotional, and moral development. Communi- ties are ideally situated to provide a wide range of supports for families through formal voluntary organizations and informal social networks. Busi- nesses have the opportunity to support family well-being through creating positive work environments, offering flexible work schedules, and provid- ing important financial benefits, such as family health insurance and child care. Local, state, and federal governments have substantial opportunities to influence the quality of family life and the availability of resources to support child needs through such diverse mechanisms as tax policies to alleviate economic hardship (e.g., earned income and child care tax cred- its), minimum wage laws to boost the incomes of low-wage workers, poli- cies to support working parents and promote the health and development of their children (e.g., child care standards and subsidies), policies to sup- port parent choice regarding employment (e.g., paid family leave), and funding for early intervention programs, among others. No single locus of responsibility can address all the needs of young children and their families. Effective policies clearly require aggregate responsibility. Finally, there is a compelling need for more constructive dialogue be- tween those who support massive public investments in early childhood services and those who question their cost and ask whether they really

CONCLUSIONS AND RECOMMENDATIONS 415 make a difference. Both perspectives have merit. Advocates of earlier and more intervention have an obligation to measure their impacts and costs. Skeptics, in turn, must acknowledge the massive scientific evidence that early childhood development is influenced by the environments in which children live. Continued “winner takes all” conflict between advocates and skeptics serves only to fuel a siege mentality in the early childhood commu- nity that undermines critical self-evaluation in the service of short-sighted self-preservation. In the final analysis, a constructive approach to early childhood policy would mobilize the best available knowledge (and pro- mote its continued growth) in order to move beyond simple questions about whether environments and early experiences make a difference. The ultimate challenge for the nation is to answer questions about how to enhance the quality of those environments and experiences in an effort to promote the health and development of young children. The charge to this committee was to blend the knowledge and insights of a broad range of disciplines to generate an integrated science of early childhood development. The charge to society is to blend the skepticism of a scientist, the passion of an advocate, the pragmatism of a policy maker, the creativity of a practitioner, and the devotion of a parent—and to use existing knowledge to ensure both a decent quality of life for all of our children and a promising future for the nation.

417 References Abbott, S. 1992 Holding on and pushing away: Comparative perspectives on an Eastern Kentucky child-rearing practice. Ethos 1:33-65. Abel, E.L. 1995 An update on incidence of FAS: FAS is not an equal opportunity birth defect. Neurotoxicology and Teratology 17(4):437-443. Aber, J.L. 1994 Poverty, violence, and child development: Untangling family and community level effects. Pp. 229-272 in Threats to Optimal Development: Integrating Biological, Psychological, and Social Risk Factors: The Minnesota Symposia on Child Psychol- ogy, Volume 27. C.A. Nelson, ed. Hillsdale, NJ: Lawrence Erlbaum Associates, Publishers. Aber, J.L., N.G. Bennett, D.C. Conley, and J. Li 1997 The effects of poverty on child health and development. Annual Review of Public Health 18:463-483. Achenbach, T.M., S.H. McConaughy, and C.T. Howell 1987 Child/adolescent behavioral and emotional problems: Implications of cross-infor- mant correlations for situational specificity. Psychological Bulletin 101:213-232. ACYF/NIMH Collaborative Mental Health Research Initiative 2000 Mental Health Within Head Start: Head Start-University Partnerships. [Online]. Available: http://www2.acf.dhhs.gov/programs/hsb/core/dox/mhhs.html [Accessed June 25, 2000]. Administration on Children Youth and Families 1998 Head Start Program Performance Measures: Second Progress Report. Washington, DC: U.S. Department of Health and Human Services. 2000 Head Start Program Performance Measures: Longitudinal Findings From the FACES Study. Washington, DC: U.S. Department of Health and Human Services.

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How we raise young children is one of today's most highly personalized and sharply politicized issues, in part because each of us can claim some level of "expertise." The debate has intensified as discoveries about our development—in the womb and in the first months and years—have reached the popular media.

How can we use our burgeoning knowledge to assure the well-being of all young children, for their own sake as well as for the sake of our nation? Drawing from new findings, this book presents important conclusions about nature-versus-nurture, the impact of being born into a working family, the effect of politics on programs for children, the costs and benefits of intervention, and other issues.

The committee issues a series of challenges to decision makers regarding the quality of child care, issues of racial and ethnic diversity, the integration of children's cognitive and emotional development, and more.

Authoritative yet accessible, From Neurons to Neighborhoods presents the evidence about "brain wiring" and how kids learn to speak, think, and regulate their behavior. It examines the effect of the climate—family, child care, community—within which the child grows.

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