The Timing of Prenatal Exposure to Maternal Cortisol and Psychosocial Stress Is Associated With Human Infant Cognitive Development

The consequences of prenatal maternal stress for development were examined in 125 full-term infants at 3, 6, and 12 months of age. Maternal cortisol and psychological state were evaluated 5 times during pregnancy. Exposure to elevated concentrations of cortisol early in gestation was associated with a slower rate of development over the 1st year and lower mental development scores at 12 months. Elevated levels of maternal cortisol late in gestation, however, were associated with accelerated cognitive development and higher scores at 12 months. Elevated levels of maternal pregnancy-specific anxiety early in pregnancy were independently associated with lower 12-month mental development scores. These data suggest that maternal cortisol and pregnancy-specific anxiety have programming influences on the developing fetus.     

Child Temperament and Total Diurnal Cortisol in Out-of-Home Center-Based Child Care and in At-Home Parental Care

The association between child temperament characteristics and total diurnal saliva cortisol in 84 children (M = 2.3 years, SD = 0.6) attending out-of-home, center-based child care and 79 children (M = 2.0 years, SD = 0.5) attending at-home parental care was examined. Saliva samples were collected during two consecutive days, that is, Sunday and Monday, with four samples taken per day. While children higher in surgency had higher total diurnal cortisol production, we did not find evidence that temperament moderated the associations between child-care context and total diurnal cortisol. Negative affectivity and effortful control were not related to cortisol output. Our findings suggest that temperamental surgency may be associated with higher total cortisol production in early childhood across child-care settings.     

Maternal employment and child cognitive outcomes in the first three years of life: the NICHD Study of Early Child Care. National Institute of Child Health and Human Development

With increased numbers of women employed in their children's first year of life and with increased attention being paid by parents and policy makers to the importance of early experiences for children, establishing the links that might exist between early maternal employment and child cognitive outcomes is more important than ever. Negative associations between maternal employment during the first year of life and children's cognitive outcomes at age 3 (and later ages) have been reported using data from the National Longitudinal Survey of Youth-Child Supplement. However, it was not known whether these findings would be replicated in another study, nor whether these results were due to features of child care (e.g., quality, type), home environment (e.g., provision of learning), and/or parenting (e.g., sensitivity). This study explored these issues using data on 900 European American children from the National Institute of Child Health and Human Development Study of Early Child Care, which provides information on child cognitive scores at 15, 24, and 36 months, as well as data about the home environment (as assessed by the Home Observation of the Measurement of the Environment Scale), parental sensitivity, and child-care quality and type over the first 3 years of life. Maternal employment by the ninth month was found to be linked to lower Bracken School Readiness scores at 36 months, with the effects more pronounced when mothers were working 30 hr or more per week and with effects more pronounced for certain subgroups (i.e., children whose mothers were not sensitive, boys, and children with married parents). Although quality of child care, home environment, and maternal sensitivity also mattered, the negative effects of working 30 hr or more per week in the first 9 months were still found, even when controlling for child-care quality, the quality of the home environment, and maternal sensitivity. Implications for policy are also discussed.     

Effects of an Early Family Intervention on Children's Memory: The Mediating Effects of Cortisol Levels

Developmental psychologists have long been concerned with the ways that early adversity influences children's long-term outcomes. In the current study, activity of the hypothalamic–pituitary–adrenal axis of medically at-risk (e.g., preterm) infants was measured as a result of maternal participation in a novel cognitively based home visitation program (versus a Healthy Start home visitation program). Maternal participation in the cognitive intervention predicted lower basal cortisol levels among infants—with reduced levels of maternal avoidance/withdrawal serving as a mediator of this relation. Lower cortisol levels in infancy, in turn, predicted higher verbal short-term memory (STM) at age 3. STM represents a cognitive ability that has importance for children's later educational outcomes. Findings provide experimental evidence concerning the pathway by which an early intervention may produce hormonal changes that can, in turn, influence children's learning outcomes.     

Intimate partner violence exposure, salivary cortisol, and childhood asthma

ObjectivesNeuroendocrine alterations may help explain health differences between intimate partner violence (IPV) exposed children and non-exposed children. We sought to determine the feasibility of having families, recruited at a child asthma visit, collect at home and return via mail child salivary samples, and whether socio-demographic variables were associated with sample return. For those returning samples, we examined whether past-year IPV exposure was associated with total cortisol output (AUC) and the magnitude of the cortisol awakening response (CAR), and whether these cortisol values were associated with asthma control.MethodsFifty-five families with an asthmatic child of any age were recruited from 2 pediatric asthma clinics. At the time of the visit, parents completed a survey packet which included a modified version of the Conflict Tactics Scale to assess IPV. Parents were given supplies to collect 3 child salivary cortisol samples (awakening, 30-min after awakening, bedtime) at home on a typical day, and return them via mail. Medical records also were abstracted.ResultsFifty-three percent (n = 29) returned child salivary samples. Families who returned samples typically returned them within 2 weeks, most commonly before we made a reminder call. Parental male sex was associated (p = .06) with increased rate of return at the trend level. In multivariable models, a 1-unit increase in IPV was significantly associated with a .93 SD increase in root-transformed total cortisol output (AUC) (un-standardized beta = 2.5; SE .59; p = .001). The odds of uncontrolled asthma were marginally higher for every nmol/l increase in CAR (OR 1.04; 95% CI 1.0, 1.1; p = .06).ConclusionsThis study provides support for the feasibility of obtaining a moderate return of salivary specimens from a convenience sample. Findings that IPV was associated with elevated total cortisol output and uncontrolled asthma was marginally associated with cortisol awakening response suggest that future studies should investigate whether cortisol mediates the IPV-child asthma relationship.     

Are there long-term effects of early child care?

Effects of early child care on children's functioning from 4(1/2) years through the end of 6th grade (M age=12.0 years) were examined in the National Institute of Child Health and Human Development Study of Early Child Care and Youth Development (n=1,364). The results indicated that although parenting was a stronger and more consistent predictor of children's development than early child-care experience, higher quality care predicted higher vocabulary scores and more exposure to center care predicted more teacher-reported externalizing problems. Discussion focuses on mechanisms responsible for these effects, the potential collective consequences of small child-care effects, and the importance of the ongoing follow-up at age 15.     

Tracing Differential Pathways of Risk: Associations Among Family Adversity,Cortisol, and Cognitive Functioning in Childhood

Guided by family risk and allostasis theoretical frameworks, the present study utilized a prospective longitudinal design to examine associations among family risk experiences, basal cortisol patterns, and cognitive functioning in children. The sample included 201 low‐income children living within a midsize city in the Northeastern United States. Children were assessed at ages 2, 3, and 4 years. Growth‐mixture modeling analyses revealed three basal cortisol patterns (elevated, moderate, low) and these remained relatively stable across time. Exposure to greater levels of family instability and maternal unresponsiveness predicted elevated and low cortisol patterns, which were associated with lower child cognitive functioning at age 4. Findings have implications for family risk processes that may underlie risk‐related disparities in child cognitive outcomes.     

The Effects of Infant Child Care on Infant-Mother Attachment Security: Results of the NICHD Study of Early Child Care NICHD Early Child Care Research Network

The aims of this investigation were to determine whether Strange Situation attachment classifications were equally valid for infants with and without extensive child-care experience in the first year of life and whether early Child Care experience, alone or in combination with mother/child factors, was associated with attachment security, and specifically with insecure-avoidant attachment. Participants were 1,153 infants and their mothers at the 10 sites of the NICHD Study of Early Child Care. Mother were interviewed, given questionnairies, and observed in play and in the home when their infants were from 1 to 15 months of age; infants were observed in child care at 6 and 15 months and in the Strange Situation at 15 months. Infants with extensive Child Care experience did not differ from infants without child-care in the distress they exhibited during separations from mother in the Strange situation or in the confidence with which trained coders assigned them attachment classifications. There were no significant main effects of Child Care experience (quality, amount, age of entry, stability, or type of care) on attachment security or avoidance. There were, however, significant man effects of maternal sensitivity and responsiveness. Significant interaction effects revealed that infants were less likely to be secure when low maternal sensitivity/responsiveness was combined with poor quality child care, more than minimal amounts of child care, or more than one care arrangement. In addition, boys experiencing many hours in care and girls in minimal amounts of care were somewhat less likely to be securely attachment.     

Cortisol Release in Infants in Response to Inoculation

Using a cross-sectional design, salivary cortisol was obtained from infants aged 2, 4, and 6 months, prior to and 15 min following an inoculation. Cortisol rose significantly following inoculation. Behavioral responses to inoculation were consistent with the observed patterns of cortisol release. Cortisol base level was significantly and negatively related to the cortisol change score. At 6 months the basal levels also were influenced by an adult-like circadian rhythm; infants tested shortly after awakening had higher basal levels than those tested later in the day. These data provide strong evidence that studies of stress and cortisol release in infants must be sensitive to basal level, circadian rhythm, and behavioral effects, and that appropriate statistical procedures should be employed.     

Longitudinal Associations of Childhood Parenting and Adolescent Health: The Mediating Influence of Social Competence

The current study examined a process through which parenting during the primary school transition contributes to cardiovascular health in adolescence, a foundational period for adult health trajectories. Using path analyses, social competence was tested as a mediator between parental sensitivity and adolescent health among 884 families. Results indicated that mothers’ and fathers’ sensitivity was associated with increasing social competence from first grade (age 7) to sixth grade (age 12), which was associated with higher awakening cortisol in ninth grade (age 15) and decreasing blood pressure from sixth to ninth grade. Results suggest that social competence mediates associations between childhood parenting and adolescent cardiovascular risk, and may be protective to children's health over time.     

Caregiver-mother partnership behavior and the quality of caregiver-child and mother-child interactions

Parent-caregiver communication, particularly concerning the behavior and experiences of the child, is a means of linking the home and child-care contexts of the child’s experience and enriching the caregiver’s and parent’s capacity to provide supportive and sensitive care of the child. The Parent-Caregiver Partnership Scale was administered to 53 mothers of 3-year-old children and to the children’s primary caregivers in child-care centers (n = 20) and less formal child-care settings (n = 33) to examine relations of mother-caregiver communication about the child to the quality of caregiver-child and mother-child interactions. More communication between mother and caregiver about the child as reported by both mothers and caregivers was significantly related to more sensitive and supportive caregiver-child interactions in child care, even after controlling for the mother’s and caregiver’s childrearing beliefs that were related to partnership behavior and the quality of child care. The quality of mother-child interaction was significantly associated with the mother’s communication with her child-care provider about her child. After controlling for maternal childrearing beliefs, mothers who engaged in more partnership behavior with their providers were more supportive and sensitive with their children.     

Role Fulfillment Mediates the Association Between Daily Family Assistance and Cortisol Awakening Response in Adolescents

Family assistance (helping the family) is associated with both positive and negative psychological and biological outcomes during adolescence. However, the association between family assistance and the hypothalamic–pituitary–adrenal (HPA) axis remains unstudied. Thus, we assess how helping the family relates to adolescents’ diurnal cortisol, an index of HPA activity, and psychological outcomes. Three hundred and seventy ethnically diverse adolescents (ages 11–18) reported daily helping behaviors and psychological experiences for 14 days and provided four saliva samples per day for 4 days. Multilevel modeling revealed that cortisol awakening response was lower the day after adolescents helped their families more. This association was explained, in part, by perceived role fulfillment (feeling like a good son, daughter, and sibling). Results highlight a possible psychological and biological benefit of assisting the family during adolescence.     

Early child care experiences and their association with family and child characteristics during middle childhood

Long-term correlates of early child care and maternal employment were examined in a representative sample of 333 6- to 12-year-old middle-class children. Intellectual, social, and behavioral development and parent-child relationships were related to nonparental infant care, center or preschool experiences, and maternal employment. Contextual analyses included child, parent, and family covariates related to choice of child care and children's development. Preschool and center day care was associated with slightly higher Wechsler Intelligence Scale for Children-Revised (WISC-R) Vocabulary scores and externalizing t scores on the Child Behavior Checklist. In addition, for African American children, center preschool experience was associated with 10-point-higher verbal intelligence scores and better ratings of positive behavioral attributes by parent and observers. Nonparental care during infancy and maternal employment patterns during the preschool years were not consistently related to the outcomes. The results of this study further support the growing consensus that the effects of early child care experiences must be considered in the context of parent, family, and child characteristics.     

Child Care and Children's Peer Interaction at 24 and 36 Months: The NICHD Study of Early Child Care

Data from the National Institute of Child Health and Human Development Study of Early Child Care were examined to determine how children's experiences in child care were related to peer competence at 24 and 36 months of age, after controlling for the effects of family and child characteristics. Peer competence was assessed using mother and caregiver ratings as well as observations of children with their peers in child care, and at 36 months from observations of dyadic play with a familiar peer. Consistent, albeit modest, relations were found between child-care experiences in the first 3 years of life and children's peer competencies. Positive, responsive caregiver behavior was the feature of child care most consistently associated with positive, skilled peer interaction in child care. Children with more experience in child-care settings with other children present were observed to be more positive and skilled in their peer play in child care, although their caregivers rated them as more negative with playmates. Children who spent more hours in child care were rated by their caregivers as more negative in peer play, but their observed peer play was not related to the quantity of care. Child-care experiences were not associated with peer competence as rated by mothers or as observed in dyadic play with a friend. Maternal sensitivity and children's cognitive and language competence predicted peer competence across all settings and informants, suggesting that family and child-care contexts may play different, but complementary roles in the development of early emerging individual differences in peer interaction.     

Cortisol levels of caregivers in child care centers as related to the quality of their caregiving

The present study examined whether stress in professional caregivers – as reflected in salivary cortisol levels – is related to the quality of their caregiving behavior. The 221 professional female caregivers in 64 child care centers were observed in three different situations and saliva samples were taken three times during the morning. Results showed that higher levels of cortisol, particularly at the beginning of the workday, predicted lower-quality caregiver behavior beyond the contribution of three other predictors, namely a higher self-reported physical workload, more children under age two in the care group, and lower caregiver age. Contrary to the expectation, higher cortisol levels did not mediate the relation between higher self-reported physical workload and more children under age two on the one hand and lower-quality caregiving behavior on the other.     

Do regulable features of child-care homes affect children’s development?

Data from the NICHD Study of Early Child Care were used to assess whether regulable features of child-care homes affect children’s development. Child-care homes selected were those in which there were at least two children and the care provider received payment for child care (ns=164 when the study children were 15 months old, 172 at 24 months, and 146 at 36 months). Caregivers who were better educated and had received more recent and higher levels of training provided richer learning environments and warmer and more sensitive caregiving. Caregivers who had more child-centered beliefs about how to handle children also provided higher quality caregiving and more stimulating homes. In addition, when settings were in compliance with recommended age-weighted group size cut-offs, caregivers provided more positive caregiving. Quality of care was not related to caregivers’ age, experience, professionalism, or mental health, or to the number of children enrolled in the child-care home or whether the caregivers’ children were present. Children with more educated and trained caregivers performed better on tests of cognitive and language development. Children who received higher quality care, in homes that were more stimulating, with caregivers who were more attentive, responsive, and emotionally supportive, did better on tests of language and cognitive development and also were rated as being more cooperative. These findings make a case for regulating caregivers’ education and training and for requiring that child-care homes not exceed the recommended age-weighted group size.     

Salivary cortisol mediates effects of poverty and parenting on executive functions in early childhood

In a predominantly low-income population-based longitudinal sample of 1,292 children followed from birth, higher level of salivary cortisol assessed at ages 7, 15, and 24 months was uniquely associated with lower executive function ability and to a lesser extent IQ at age 3 years. Measures of positive and negative aspects of parenting and household risk were also uniquely related to both executive functions and IQ. The effect of positive parenting on executive functions was partially mediated through cortisol. Typical or resting level of cortisol was increased in African American relative to White participants. In combination with positive and negative parenting and household risk, cortisol mediated effects of income-to-need, maternal education, and African American ethnicity on child cognitive ability.     

Prematurity,maternal emotional distress,and infant social responsiveness among Arab-Bedouin families: The role of social support as a resilience factor

This study investigated predictors of early infant social development and the role of social support as a resilience factor among Arab-Bedouin families. We propose a mediation model in which social support will be related to maternal postpartum emotional distress (PPED), which in turn will be related to infant social responsiveness. One hundred five Arab-Bedouin mothers (age range = 17–44 years) and their preterm (n = 48) and full-term (n = 57) infants were recruited shortly after birth and were followed up at age 12 months. Findings demonstrate that, among the preterm group, higher levels of social support predicted lower levels of maternal PPED, and this, in turn, predicted higher levels of infant social responsiveness.     

The Relation of Preschool Child-Care Quality to Children''s Cognitive and Social Developmental Trajectories through Second Grade

The cognitive and socioemotional development of 733 children was examined longitudinally from ages 4 to 8 years as a function of the quality of their preschool experiences in community child-care centers, after adjusting for family selection factors related to child-care quality and development. These results provide evidence that child-care quality has a modest long-term effect on children's patterns of cognitive and socioemotional development at least through kindergarten, and in some cases, through second grade. Differential effects on children's development were found for two aspects of child-care quality. Observed classroom practices were related to children's language and academic skills, whereas the closeness of the teacher-child relationship was related to both cognitive and social skills, with the strongest effects for the latter. Moderating influences of family characteristics were observed for some outcomes, indicating stronger positive effects of child-care quality for children from more at-risk backgrounds. These findings contribute further evidence of the long-term influences of the quality of child-care environments on children's cognitive and social skills through the elementary school years and are consistent with a bioecological model of development that considers the multiple environmental contexts that the child experiences.     

Children's wellbeing and cortisol levels in home-based and center-based childcare

The central question in this study is whether individual variability in children's cortisol levels and wellbeing at childcare can be explained by indices of quality of care and child characteristics. Participants were 71 children from childcare homes and 45 children from childcare centers in the age range of 20–40 months. In both types of settings equivalent measures and procedures were used. In home-based childcare, children experienced higher caregiver sensitivity, lower noise levels, and showed higher wellbeing compared to children in childcare centers. Caregiver sensitivity in home-based childcare – but not in center care – was positively associated with children's wellbeing. Additionally, children displayed higher cortisol levels at childcare than at home, irrespective of type of care. In home-based childcare, lower caregiver sensitivity was associated with higher total production of salivary cortisol during the day. In center-based childcare, lower global quality of care was associated with a rise in cortisol between 11 AM and 3 PM during the day. Quality of care is an important factor in young children's wellbeing and HPA stress reactivity.