A Competing Neurobehavioral Decision Systems model of SES-related health and behavioral disparities.

We propose that executive dysfunction is an important component relating to the socio-economic status gradient of select health behaviors. We review and find evidence supporting an SES gradient associated with (1) negative health behaviors (e.g., obesity, excessive use of alcohol, tobacco and other substances), and (2) executive dysfunction. Moreover, the evidence supports that stress and insufficient cognitive resources contribute to executive dysfunction and that executive dysfunction is evident among individuals who smoke cigarettes, are obese, abuse alcohol, and use illicit drugs. Collectively these data support the dual system model of cognitive control, referred to here as the Competing Neurobehavioral Decision Systems hypothesis. The implications of these relationships for intervention and social justice considerations are discussed.

Which children benefit the most from early intervention?

Recent findings from three separate studies support and extend a large and growing body of early-intervention research literature spanning 30 years. The literature is consistent in demonstrating positive developmental outcomes as a result of intensive early intervention for children of low-income and undereducated families. New analyses confirm that maternal intelligence is a key factor in children's intellectual development, especially when these children are not provided with intensive early intervention. Fortunately, children whose mothers have low IQs respond positively to intensive, high-quality early intervention, which leads to a dramatic reduction in their rates of mental retardation during the intervention program. Unresolved issues include how best routinely to identify children and families who will benefit from such programs, how early to begin programs and for how long to continue them to produce desirable developmental outcomes, and whether sufficient public and political will exists to scale-up early intervention efforts to match the magnitude of the problem in our society.

Otitis media in early childhood and cognitive, academic, and classroom performance of the school-aged child.

The relationship between the occurrence of otitis media during the first 3 years of life and cognitive, academic, and classroom performance during the third year of elementary school was evaluated in 44 socioeconomically disadvantaged children. The children attended a research day-care program where their otitis media experience and psychoeducational development were documented prospectively from birth. No significant relationship was found between otitis media in early childhood and performance on tests of verbal intelligence or academic achievement in the third year of school. The number of days of otitis media before 3 years of age was significantly correlated with teachers' ratings of children's attentional behavior in the classroom, however. Children with more early otitis media tended to be rated as less task oriented and less able to work independently than children with less otitis media. This was an exploratory study of a small number of children. Further study of the potential association is needed.

Infant Health and Development Program for low birth weight, premature infants: program elements, family participation, and child intelligence.

The Infant Health and Development Program was an eight-site randomized controlled trial testing the efficacy of early intervention to enhance the cognitive, behavioral, and health status of low birth weight, premature infants. The 377 intervention families received for the first 3 years of life: (1) pediatric follow-up, (2) home visits, (3) parent support groups, and (4) a systematic educational program provided in specialized child development centers. The control group (n = 608) received the same pediatric follow-up and referral services only. This paper describes the delivery of the intervention and its outcomes. A Family Participation Index that was the sum of participation frequencies in each of the program modalities unique to the intervention revealed that program implementation was not different across the eight sites. Index scores did not vary systematically with mother's ethnicity, age, or education or with child's birth weight, gender, or neonatal health status; but they were positively related to children's IQ scores at age 3. Only 1.9% of children of families in the highest tercile of participation scored in the mentally retarded range (IQ less than or equal to 70), whereas 3.5% and 13% of children in the middle and lowest participation terciles, respectively, scored in the retarded range. Similar findings were obtained for borderline intellectual functioning. These findings are consistent with previous research linking intensity of intervention services with degree of positive cognitive outcomes for high-risk infants. The determinants of variations in individual family participation remain unknown.

Otitis media in early childhood and its relationship to later verbal and academic performance.

The relationship between the occurrence of otitis media with effusion during the first 3 years of life and subsequent verbal and academic performance was examined in 61 socioeconomically disadvantaged children who attended a research day-care program. Study children were participants in a longitudinal study of child development in which the number of episodes of otitis media and duration of each otitis episode were reported prospectively from infancy. The incidence of otitis media was highest during the first 2 years of life. Bilateral otitis media accounted for 66% of the days with otitis media with effusion. Standardized tests of intelligence and academic performance were administered to the children when they were 3 1/2 to 6 years of age. No evidence of associations between measures of early childhood otitis media experience and these measures of verbal or academic functioning was found in this study population.

Early intervention and early experience.

For 4 decades, vigorous efforts have been based on the premise that early intervention for children of poverty and, more recently, for children with developmental disabilities can yield significant improvements in cognitive, academic, and social outcomes. The history of these efforts is briefly summarized and a conceptual framework presented to understand the design, research, and policy relevance of these early interventions. This framework, biosocial developmental contextualism, derives from social ecology, developmental systems theory, developmental epidemiology, and developmental neurobiology. This integrative perspective predicts that fragmented, weak efforts in early intervention are not likely to succeed, whereas intensive, high-quality, ecologically pervasive interventions can and do. Relevant evidence is summarized in 6 principles about efficacy of early intervention. The public policy challenge in early intervention is to contain costs by more precisely targeting early interventions to those who most need and benefit from these interventions. The empirical evidence on biobehavioral effects of early experience and early intervention has direct relevance to federal and state policy development and resource allocation.

Family support in the home. Programs, policy, and social change.

The need for a coordinated national policy on family support in the home is discussed. First, the history of home visiting programs is reviewed. Then, recommendations for practice, training, and research in family support programs are presented. A discussion of the impact of new federal initiatives on family support programs and research demonstration efforts follows.

The development of cognitive and academic abilities: growth curves from an early childhood educational experiment.

In the Abecedarian Project, a prospective randomized trial, the effects of early educational intervention on patterns of cognitive and academic development among poor, minority children were examined. Participants in the follow-up were 104 of the original 111 participants in the study (98% African American). Early treatment was full-time, high-quality, educational child care from infancy to age 5. Cognitive test scores collected between the ages of 3 and 21 years and academic test scores from 8 to 21 years were analyzed. Treated children, on average, attained higher scores on both cognitive and academic tests, with moderate to large treatment effect sizes observed through age 21. Preschool cognitive gains accounted for a substantial portion of treatment differences in the development of reading and math skills. Intensive early childhood education can have long-lasting effects on cognitive and academic development.

Early intervention: why, for whom, how, and at what cost?

When the concept of intervention is applied to human development, the goal is usually to enhance functioning or to prevent some unwanted condition. During the past 20 years, the United States has committed itself to an early intervention position for young children who are socio-economically, educationally, or physically disadvantaged. This article summarizes the knowledge base concerning early educational interventions and to recommend actions concerning public policy and associated research.

Early intervention for low birthweight, premature infants: participation and intellectual development.

The Infant Health and Development Program was an eight-site randomized controlled trial of comprehensive early intervention for low birthweight, premature infants during the first 3 years of life in which intellectual development was an outcome of major importance. At 24 and 36 months, but not at 12 months, higher Mental Development Index and IQ were associated with higher levels of participation in the intervention. In a longitudinal analysis of these data, we found that the intellectual development of children in the intervention group was associated with each of the three intervention modalities (the number of home visits received, days attended at child centers, and the number of parent meetings attended) but not with children's background characteristics (i.e., maternal education, birthweight). We suggest that these findings represent a dose-response relation between intervention and outcome.

Preventive education for high-risk children: cognitive consequences of the Carolina Abecedarian Project.

Longitudinal mental test scores for 54 educationally treated disadvantaged preschool children at high-risk for nonbiologically based mild mental retardation and 53 control children were compared. The educationally treated children were in a child-centered prevention-oriented intervention program delivered in a daycare setting from infancy to age 5. Language, cognitive, perceptual-motor, and social development were stressed. Children were examined with age-appropriate tests of development at 6, 12, 18, 24, 30, 42, 48, and 54 months of age. Beginning at 18 months, and on every test occasion thereafter, educationally treated children significantly outscored control group children on mental tests; treated children consistently scored at the national average whereas control children's scores declined from the average level at 12 months to below average at 18 months and thereafter. Implications of the results for early intervention were discussed.

Biological nonoptimality and quality of postnatal environment as codeterminants of intellectual development.

The relation of nonoptimal condition at birth to the intellectual development of children reared in 2 different environments was investigated in a 4 1/2-year longitudinal experiment. Subjects were 80 disadvantaged children, half of whom were randomly assigned at birth to a day-care program designed to prevent mild mental retardation and half to an educationally untreated control group. All subjects for this report were full-term and weighed over 2,500 grams at birth; condition at birth was considered nonoptimal if the 1-min Apgar score was less than or equal to 8. Results indicated that nonoptimal perinatal status had significant adverse effects on 4 1/2-year scores on the McCarthy Scales of Children's Abilities in the control group (p less than .01); however, test scores of children with optimal or nonoptimal Apgars did not differ within the group that received educational treatment. The results provide support for a framework stressing initial biological vulnerability and subsequent environmental insufficiency as cumulative risk factors in the development of children from low SES families.

Effective early intervention.

Recent positive findings from three early educational intervention programs designed to prevent mental retardation as well as to improve school readiness and educational progress were summarized. Evidence was presented to show that without early intervention, children of low-IQ mothers are particularly at-risk for poor intellectual outcomes and that such children respond very favorably to intensive, systematic early intervention. In addition, new findings indicate a strong relation between the intensity of the early educational intervention and the amount of benefits realized by individual children. Further, there is new evidence that the benefits of continuous educational intervention over the first 5 years of life last at least until early adolescence. We identified six essential types of experiences that we think account for the positive outcomes and that need to be systematically included to the maximum feasible level in future early intervention programs.

Fetal malnutrition: an experimental study of its consequences on infant development in two caregiving environments.

Infants from low socioeconomic status families were randomly assigned to an instructional day-care program designed to prevent socioculturally caused mental retardation or to a nonintervention control group. This assignment procedure resulted in an equal distribution of full-term, full-birth-weight, fetally malnourished babies in 2 environments varying in intellectually supportive characteristics. The condition of fetal malnourishment was defined by infants having low ponderal indices (PI). At 3 months of age low-PI infants showed lower Bayley Mental Development Index (MDI) scores than normal-PI infants, independent of the environment. In the control group low-PI infants still had lower MDI scores than normal-PI infants at 18 months of age. However, at that time in the day-care group, low-PI infants scored as well as normal-PI infants. These findings were replicated when the infants were 24 months of age with Stanford-Binet intelligence tests. Observations of mothers' involvement with their infants showed that, although all groups had similar amounts of maternal involvement when the babies were 6 months of age, the mothers of low-PI infants in the control group showed less involvement with their infants at 18 months of age than the other mothers. We suggest that this longitudinal study provides experimental evidence for a transactional model of development which emphasizes both newborn infant characteristics and environmental quality as cocontributors to the process of development.

Effects of early intervention on intellectual and academic achievement: a follow-up study of children from low-income families.

Follow-up data, obtained 4-7 years after intervention ended, are presented for the Carolina Abecedarian Project, an experimental study of early childhood educational intervention for children from poverty families. Subjects were randomly assigned to 1 of 4 intervention conditions: educational treatment from infancy through 3 years in public school (up to age 8); preschool treatment only (infancy to age 5); primary school treatment only (age 5-8 years), or an untreated control group. Positive effects of preschool treatment on intellectual development and academic achievement were maintained through age 12. School-age treatment alone was less effective. Results generally supported an intensity hypothesis in that scores on cognitive and academic achievement measures increased as duration of treatment increased.

Prevention of intellectual disabilities: early interventions to improve cognitive development.

This paper presents a conceptual framework that has guided three randomized, controlled early intervention trials designed to improve cognitive development and social competence in high-risk young children from birth to 3 years of age. Two of the projects (Abecedarian and CARE) enrolled infants from economically and socially low-resource families and the other project (IHDP) was an eight-site randomized controlled trial with 985 low birth-weight and premature infants and their families. IHDP families varied widely in their economic and social resources. Results consistently indicated positive effects of the intervention on child IQ during the first 3 years of life. Children from the lowest resource families consistently benefited the most from the early intervention.