Facial expressivity to acute pain in cocaine-exposed toddlers

Parenting in the Context of the Child: Genetic and Social Processes

The focus on the role of parenting in child development has a long-standing history. When measures of parenting precede changes in child development, researchers typically infer a causal role of parenting practices and attitudes on child development. However, this research is usually conducted with parents raising their own biological offspring. Such research designs cannot account for the effects of genes that are common to parents and children, nor for genetically influenced traits in children that influence how they are parented and how parenting affects them. The aim of this monograph is to provide a clearer view of parenting by synthesizing findings from the Early Growth and Development Study (EGDS). EGDS is a longitudinal study of adopted children, their birth parents, and their rearing parents studied across infancy and childhood. Families (N = 561) were recruited in the United States through adoption agencies between 2000 and 2010. Data collection began when adoptees were 9 months old (males = 57.2%; White 54.5%, Black 13.2%, Hispanic/Latinx 13.4%, Multiracial 17.8%, other 1.1%). The median child age at adoption placement was 2 days (M = 5.58, SD = 11.32). Adoptive parents were predominantly in their 30s, White, and coming from upper-middle- or upper-class backgrounds with high educational attainment (a mode at 4-year college or graduate degree). Most adoptive parents were heterosexual couples, and were married at the beginning of the project. The birth parent sample was more racially and ethnically diverse, but the majority (70%) were White. At the beginning of the study, most birth mothers and fathers were in their 20s, with a mode of educational attainment at high school degree, and few of them were married. We have been following these family members over time, assessing their genetic influences, prenatal environment, rearing environment, and child development. Controlling for effects of genes common to parents and children, we confirmed some previously reported associations between parenting, parent psychopathology, and marital adjustment in relation to child problematic and prosocial behavior. We also observed effects of children's heritable characteristics, characteristics thought to be transmitted from parent to child by genetic means, on their parents and how those effects contributed to subsequent child development. For example, we found that genetically influenced child impulsivity and social withdrawal both elicited harsh parenting, whereas a genetically influenced sunny disposition elicited parental warmth. We found numerous instances of children's genetically influenced characteristics that enhanced positive parental influences on child development or that protected them from harsh parenting. Integrating our findings, we propose a new, genetically informed process model of parenting. We posit that parents implicitly or explicitly detect genetically influenced liabilities and assets in their children. We also suggest future research into factors such as marital adjustment, that favor parents responding with appropriate protection or enhancement. Our findings illustrate a productive use of genetic information in prevention research: helping parents respond effectively to a profile of child strengths and challenges rather than using genetic information simply to identify some children unresponsive to current preventive interventions.

Child Effects on Parental Negativity: The Role of Heritable and Prenatal Factors

This study examined two possible mechanisms, evocative gene-environment correlation and prenatal factors, in accounting for child effects on parental negativity. Participants included 561 children adopted at birth, and their adoptive parents and birth parents within a prospective longitudinal adoption study. Findings indicated child effects on parental negativity, such that toddlers' negative reactivity at 18 months was positively associated with adoptive parents' over-reactive and hostile parenting at 27 months. Furthermore, we found that child effects on parental negativity were partially due to heritable (e.g., birth mother [BM] internalizing problems and substance use) and prenatal factors (e.g., BM illicit drug use during pregnancy) that influence children's negative reactivity at 18 months. This study provides critical evidence for "child on parent" effects.

Psychological Distress Among School-Aged Children with and Without Intrauterine Cocaine Exposure: Perinatal Versus Contextual Effects

Whether intrauterine cocaine exposure (IUCE) explains unique variance in psychiatric functioning among school age children, even after controlling for other biological and social risk factors, has not been fully delineated. As part of a longitudinal birth cohort study of children with and without IUCE, we conducted and analyzed data based on structured clinical interviews with 105 children (57% male) and their caregivers when the child was approximately 8.5 years old; 47% of the children had experienced IUCE. Interviews included past and current major psychological disorders and sub-threshold mental health symptoms. Potential covariates were ascertained by interviews of birth mothers and other caregivers from shortly after the child's birth until the 8.5-year visit. More than one-third of children met DSM-IV criteria for one or more mood, anxiety, attention deficit, or disruptive behavior disorders. IUCE was not significantly associated with children's history of psychological distress, in either bivariate or multiple logistic regressions. In contrast, birth mothers' acknowledgement of greater psychiatric distress at baseline and higher levels of alcohol consumption during pregnancy, and at 8.5 years caregivers' reports of their own psychological distress, and children's lower IQ were predictors of higher rates of psychological morbidity. Findings are consistent with prior reports suggesting that, regardless of IUCE status, children from low-income, urban backgrounds are at heightened risk for psychological distress. Results underscore the need for closer monitoring of the mental health of children living in low-income households, with or without intrauterine substance exposures, to facilitate access to appropriate services.

Effects of prenatal substance exposure on infant temperament vary by context

This was a prospective longitudinal multisite study of the effects of prenatal cocaine and/or opiate exposure on temperament in 4-month-olds of the Maternal Lifestyle Study (N = 958: 366 cocaine exposed, 37 opiate exposed, 33 exposed to both drugs, 522 matched comparison). The study evaluated positivity and negativity during The Behavior Assessment of Infant Temperament (Garcia Coll et al., 1988). Parents rated temperament (Infant Behavior Questionnaire; Rothbart, 1981). Cocaine-exposed infants showed less positivity overall, mainly during activity and threshold items, more negativity during sociability items, and less negativity during irritability and threshold items. Latent profile analysis indicated individual temperament patterns were best described by three groups: low/moderate overall reactivity, high social negative reactivity, and high nonsocial negative reactivity. Infants with heavy cocaine exposure were more likely in high social negative reactivity profile, were less negative during threshold items, and required longer soothing intervention. Cocaine- and opiate-exposed infants scored lower on Infant Behavior Questionnaire smiling and laughter and duration of orienting scales. Opiate-exposed infants were rated as less respondent to soothing. By including a multitask measure of temperament we were able to show context-specific behavioral dysregulation in prenatally cocaine-exposed infants. The findings indicate flatter temperament may be specific to nonsocial contexts, whereas social interactions may be more distressing for cocaine-exposed infants.

Level of prenatal cocaine exposure and infant-caregiver attachment behavior

The objective of this longitudinal prospective cohort study was to determine whether level of prenatal cocaine exposure, or the interaction between level of prenatal cocaine exposure and contextual risk variables, was associated with a higher rate of infant-caregiver insecure attachment and disorganized attachment, or with alterations in infant crying or avoidant behavior, after controlling for prenatal exposure to alcohol, tobacco, and marijuana, the quality of the proximal caregiving environment, and other covariates. Subjects were 154 full-term 12-month-old infants (64 unexposed, 61 with lighter cocaine exposure, 29 with heavier cocaine exposure) and their primary caregivers from low-income, urban backgrounds. Exposure status was determined in the maternity ward by biologic assay (infant meconium and/or maternal or infant urine) and maternal self-report. At the 12-month follow-up visit, infants were videotaped with their primary caregiver in Ainsworth's Strange Situation. Reliable coders masked to exposure status scored videotapes for attachment variables, amount of crying, and level of avoidance. Contrary to popular perceptions, level of prenatal cocaine exposure was not significantly related to secure/insecure attachment status, disorganized attachment status, or rated level of felt security. Foster care status also was not associated with attachment status. However, heavier prenatal cocaine exposure, in interaction with maternal contextual variables (public assistance or multiparity) was associated with alterations in infant socio-affective behavior, including a higher level of behavioral disorganization, more avoidance of the caregiver, and less crying.

Prolonged prenatal psychotropic medication exposure alters neonatal acute pain response

Selective serotonin reuptake inhibitors (SSRIs) and benzodiazepines are frequently used to treat maternal depression during pregnancy, however the effect of increased serotonin (5HT) and gamma-amino-butyric acid (GABA) agonists in the fetal human brain remains unknown. 5HT and GABA are active during fetal neurologic growth and play early roles in pain modulation, therefore, if prolonged prenatal exposure alters neurodevelopment this may become evident in altered neonatal pain responses. To examine biologic and behavioral effects of prenatal exposure, neonatal responses to acute pain (phenylketonuria heel lance) in infants with prolonged prenatal exposure were examined. Facial action (Neonatal Facial Coding System) and cardiac autonomic reactivity derived from the relationship between respiratory activity and short term variations of heart rate (HRV) were compared between 22 infants with SSRI exposure (SE) [fluoxetine (n = 7), paroxetine (n = 11), sertraline (n = 4)]; 16 infants exposed to SSRIs and clonazepam (SE+) [paroxetine (n = 14), fluoxetine (n = 2)]; and 23 nonexposed infants during baseline, lance, and recovery periods of a heel lance. Length of maternal SSRI use did not vary significantly between exposure groups-[mean (range)] SE:SE+ 183 (31-281):141 (54-282) d (p > 0.05). Infants exposed to SE and SE+ displayed significantly less facial activity to heel lance than control infants. Mean HR increased with lance, but was significantly lower in SE infants during recovery. Using measures of HRV and the transfer relationship between heart rate and respiration, SSRI infants had a greater return of parasympathetic cardiac modulation in the recovery period, whereas a sustained sympathetic response continued in the control group. Prolonged prenatal SSRI exposure appears to be associated with reduced behavioral pain responses and increased parasympathetic cardiac modulation in recovery following an acute neonatal noxious event. Possible 5HT-mediated pain inhibition, pharmacologic factors and the developmental course remain to be studied.