Early childhood trauma exposure and neurocognitive and emotional processes: Associations in young children in a partial hospital program

Early childhood trauma has been linked to neurocognitive and emotional processing deficits in older children, yet much less is known about these associations in young children. Early childhood is an important developmental period in which to examine relations between trauma and executive functioning/emotion reactivity, given that these capacities are rapidly developing and are potential transdiagnostic factors implicated in the development of psychopathology. This cross-sectional study examined associations between cumulative trauma, interpersonal trauma, and components of executive functioning, episodic memory, and emotion reactivity, conceptualized using the RDoC framework and assessed with observational and performance-based measures, in a sample of 90 children (ages 4-7) admitted to a partial hospital program. Children who had experienced two or more categories of trauma had lower scores in episodic memory, global cognition, and inhibitory control as measured in a relational (but not computerized) task, when compared to children with less or no trauma. Interpersonal trauma was similarly associated with global cognition and relational inhibitory control. Family contextual factors did not moderate associations. Findings support examining inhibitory control in both relationally significant and decontextualized paradigms in early childhood, and underscore the importance of investigating multiple neurocognitive and emotional processes simultaneously to identify potential targets for early intervention.

Examining the Biological Impacts of Parent-Child Relationship Dynamics on Preschool-Aged Children who have Experienced Adversity

Parent-child relationship dynamics have been shown to predict socioemotional and behavioral outcomes for children, but little is known about how they may affect biological development. The aim of this study was to test if observational assessments of parent-child relationship dynamics (cohesion, enmeshment, and disengagement) were associated with three biological indices of early life adversity and downstream health risk: (1) methylation of the glucocorticoid receptor gene (NR3C1), (2) telomere attrition, and (3) mitochondrial biogenesis, indexed by mitochondrial DNA copy number (mtDNAcn), all of which were measured in children's saliva. We tested hypotheses using a sample of 254 preschool-aged children (M age = 51.04 months) with and without child welfare-substantiated maltreatment (52% with documented case of moderate-severe maltreatment) who were racially and ethnically diverse (17% Black, 40% White, 23% biracial, and 20% other races; 45% Hispanic) and from primarily low-income backgrounds (91% qualified for public assistance). Results of path analyses revealed that: (1) higher parent-child cohesion was associated with lower levels of methylation of NR3C1 exon 1D and longer telomeres, and (2) higher parent-child disengagement was associated with higher levels of methylation of NR3C1 exon 1D and shorter telomeres. Results suggest that parent-child relationship dynamics may have distinct biological effects on children.

Maternal Childhood Adversity and Infant Epigenetic Aging: Moderation by Restless Sleep During Pregnancy

Maternal exposure to childhood adversity is associated with detrimental health outcomes throughout the lifespan and may have implications for offspring. Evidence links maternal adverse childhood experiences (ACEs) to detrimental birth outcomes, yet the impact on the infant's epigenome is unclear. Moreover, maternal sleep habits during pregnancy may influence this association. Here, we explore whether restless sleep during pregnancy moderates the association between exposure to maternal childhood adversity and infant epigenetic age acceleration in 332 mother-infant dyads (56% female; 39% Black; 25% Hispanic). During the 2nd trimester, mothers self-reported childhood adversity and past-week restless sleep; DNA methylation from umbilical vein endothelial cells was used to estimate five epigenetic clocks. Multivariable linear regression was used to test study hypotheses. Despite no evidence of main effects, there was evidence of an interaction between maternal ACEs and restless sleep in predicting infant epigenetic age acceleration using the EPIC Gestational Age clock. Only infants whose mothers reported exposure to both ACEs and restless sleep demonstrated accelerated epigenetic aging. Results provide preliminary evidence that maternal childhood adversity and sleep may influence the infant epigenome.

Circulating Cell-Free Mitochondrial DNA and Depressive Symptoms Among Low-Active Adults Who Smoke

OBJECTIVES

Mitochondrial dysfunction is implicated in the pathophysiology of psychiatric disorders. Levels of circulating cell-free mitochondrial DNA (cf-mtDNA) are observed to be altered in depression. However, the few studies that have measured cf-mtDNA in depression have reported conflicting findings. This study examined cf-mtDNA and depressive symptoms in low-active adults who smoke.

METHODS

Participants were adults 18 to 65 years old ( N = 109; 76% female) with low baseline physical activity and depressive symptoms recruited for a smoking cessation study. Self-report measures assessed depression severity, positive and negative affect, and behavioral activation. Blood was collected and analyzed for cf-mtDNA. Relationships between depressive symptoms and cf-mtDNA were examined with correlations and linear regression.

RESULTS

Levels of cf-mtDNA were associated with categorically defined depression (Center for Epidemiologic Studies Depression Scale score >15), lower positive affect, and decreased behavioral activation ( p < .05). Relationships remained significant after adjustment for age, sex, and nicotine dependence. In a linear regression model including all depressive symptom measures as predictors, Center for Epidemiologic Studies Depression Scale group and lower positive affect remained significant.

CONCLUSIONS

This work suggests that mitochondrial changes are associated with depressive symptoms in low-active adults who smoke. Higher levels of cf-mtDNA in association with depression and with lower positive affect and decreased behavioral activation are consistent with a possible role for mitochondrial function in depressive symptoms.

Reflective supervision and consultation and its impact within early childhood-serving programs: A systematic review

Reflective supervision and consultation (RS/C) is regarded as best practice within the infant/early childhood mental health field. Benefits of RS/C on the early childhood workforce and children and families have been demonstrated through case studies, conceptual pieces, and individual research studies. However, findings across studies have not been summarized using gold-standard methodology, thus the state of existing empirical support for RS/C is unclear. This systematic review examined the collective evidence for RS/C across diverse early childhood-serving programs. Electronic databases were searched to identify studies investigating associations between RS/C and professionals' reflective capacity and well-being, child/family outcomes, and implementation factors. Twenty-eight papers were identified. Studies showed positive associations between RS/C and early childhood-serving professionals' reflective capacity and well-being, with qualitative studies reporting more consistent results than studies using quantitative methods. Many methodological limitations were identified, including incomplete reporting of study designs and participant characteristics, variability in outcome measures, and lack of randomization and comparison groups. Furthermore, few studies examined child and family outcomes. Therefore, while RS/C shows great promise, it was difficult to ascertain its overall effectiveness from an empirical standpoint. Establishing RS/C as an empirically supported approach will be possible with more rigorous research.

Maternal perinatal hypertensive disorders and parenting in infancy

Maternal mental health strongly influences parenting during infancy. However, it is unclear whether maternal physical health conditions in the perinatal period may also impact parenting. Examining the association of hypertensive disorders - a common physical health problem in pregnancy - with subsequent parenting behaviors is an important first step in understanding the connection between maternal physical health and parenting during this critical developmental period. This study evaluated whether hypertensive disorders of pregnancy (HDP) and hypertensive disorders (HD) diagnosed after the birth of the infant were associated with parenting self-efficacy, parenting stress, and observed parental responsiveness during mother-infant interactions at 6 and 12 months postpartum among a sample of racially and ethnically diverse mothers and their infants (N = 295). Results showed that mothers with an HDP or HD diagnosis had lower levels of parenting self-efficacy, higher levels of parenting stress, and lower levels of observed parental responsiveness compared to mothers without an HDP or HD diagnosis. Given that women with childhood adversity are at higher risk for experiencing HDP/HD and may have more difficulties with parenting compared to women without childhood adversity, we utilized a sample of mothers wherein most had experienced at least one form of adversity in their childhoods. Exploratory analyses revealed that HDP/HD moderated the relation between early life experiences and parenting outcomes in all but one model. Associations between HDP/HD and parenting are discussed, with implications for how we understand maternal physical health as a determinant of parenting in the perinatal period.

Understanding links between maternal perinatal posttraumatic stress symptoms and infant socioemotional and physical health

Maternal posttraumatic stress symptoms (PTSS) are associated with adverse consequences for older children, but very few studies have examined links between perinatal maternal PTSS and infant outcomes. Trauma exposure and psychopathology, including PTSS, is often heightened for women during pregnancy through 1 year postpartum. Therefore, the perinatal period may be a critical time for understanding the risk maternal PTSS and other mental health factors pose to the socioemotional and physical health of infants. The present study explored the relation between maternal PTSS and infant socioemotional and physical health problems in a sample of racially and ethnically diverse mother-infant dyads (N = 295) assessed prenatally and at 12 months postpartum. This study also examined whether there are: (1) moderating effects of maternal depressive symptoms and parenting stress on these associations and (2) indirect effects of PTSS on infant outcomes through observed maternal sensitivity. Results indicated that postpartum depressive symptoms and parenting stress, rather than PTSS, were associated with greater infant socioemotional health problems. However, prenatal PTSS were associated with greater infant physical health problems when mothers also reported clinically significant levels of postpartum depressive symptoms. Maternal sensitivity was not associated with maternal PTSS, depressive symptoms, or parenting stress, nor was it related to infant socioemotional and physical health; thus, maternal sensitivity was not tested as an intermediary mechanism linking maternal mental health with infant outcomes. Implications for promoting maternal mental health in the perinatal period to bolster socioemotional and physical health of infants are discussed.

The Family is the Patient: Promoting Early Childhood Mental Health in Pediatric Care

Advances in developmental psychology, child psychiatry, and allied disciplines have pointed to events and experiences in the early years as the origin of many adult mental health challenges. Yet, children's mental health services still largely lack a developmental or prevention-focused orientation, with most referrals to mental health professionals occurring late, once problems are well established. An early childhood mental health system rooted in the principles of life-course health development would take a very different approach to designing, testing, and implementing prevention and intervention strategies directed toward early child mental health. Priorities for such a system include supporting healthy family environments, parent-child and family relationships, parents' emotional/behavioral health, and family routines as a means of providing the best possible neurobiological foundation for mental health across the life span. The system would include proactive, trauma-informed, multidisciplinary care, with integrated mental health and social services support embedded in pediatric primary care settings. Novel intervention approaches in need of further research include 2-generational dyadic interventions designed to improve the mental health of parents and children, mental health-oriented telemedicine, and contingency management (CM) strategies. Integral to this Life Course Health Development reformulation is a commitment by all organizations supporting children to primordial and primary prevention strategies to reduce racial and socioeconomic disparities in all settings. We contend that it is the family, not the individual child, that ought to be the identified target of these redesigned approaches, delivered through a transformed pediatric system with anticipated benefits for multiple health outcomes across the life course.

A Review of Associations between Externalizing Behaviors and Prenatal Cannabis Exposure: Limitations & Future Directions

In utero cannabis exposure can disrupt fetal development and increase risk for various behavioral disruptions, including hyperactivity, inattention, delinquent behaviors, and later substance abuse, among others. This review summarizes the findings from contemporary investigations linking prenatal cannabis exposure to the development of psychopathology and identifies the limitations within the literature, which constrain our interpretations and generalizability. These limitations include a lack of genetic/familial control for confounding and limited data examining real world products, the full range of cannabinoids, and motives for use specifically in pregnant women. Taken together, our review reveals the need to continue to improve upon study designs in order to allow researchers to accurately draw conclusions about the development of behavioral consequences of prenatal cannabis exposure. Findings from such studies would inform policy and practices regarding cannabis use during pregnancy and move the field toward developing a comprehensive teratogenic profile of cannabis similar to what is characterized in the prenatal alcohol and tobacco literature.

Cascades of Risk Linking Intimate Partner Violence and Adverse Childhood Experiences to Less Sensitive Caregiving During Infancy

This study evaluated if maternal intimate partner violence (IPV) had indirect effects on sensitive parenting in infancy through prenatal depressive symptoms and postpartum parenting stress and if maternal adverse childhood experiences (ACEs) moderated these indirect effects. We hypothesized that: (a) IPV would be associated with greater prenatal depressive symptoms, which would predict greater postpartum parenting stress, and ultimately less sensitive parenting and (b) the link between IPV and depressive symptoms would be strongest for mothers with high ACEs. Participants included 295 mothers and their infants who were assessed prenatally and at 12 months postpartum. Path analyses indicated that mothers with higher IPV endorsed greater prenatal depressive symptoms, which was in turn associated with postpartum parenting stress, and ultimately less sensitive parenting behavior. Moderation analyses revealed that these indirect effects varied as a function of maternal ACEs, with the link between IPV and depressive symptoms only present for mothers who reported high ACEs. Because less sensitive caregiving is often an early indicator of child maltreatment risk, understanding precursors to sensitivity is critical to increase precision in parenting interventions designed to reduce risk for maltreatment. Results may inform evidence-based preventive interventions for mothers and infants at high-risk for child abuse and neglect.

A systematic review of childhood maltreatment and DNA methylation: candidate gene and epigenome-wide approaches

Childhood maltreatment is a major risk factor for chronic and severe mental and physical health problems across the lifespan. Increasing evidence supports the hypothesis that maltreatment is associated with epigenetic changes that may subsequently serve as mechanisms of disease. The current review uses a systematic approach to identify and summarize the literature related to childhood maltreatment and alterations in DNA methylation in humans. A total of 100 empirical articles were identified in our systematic review of research published prior to or during March 2020, including studies that focused on candidate genes and studies that leveraged epigenome-wide data in both children and adults. Themes arising from the literature, including consistent and inconsistent patterns of results, are presented. Several directions for future research, including important methodological considerations for future study design, are discussed. Taken together, the literature on childhood maltreatment and DNA methylation underscores the complexity of transactions between the environment and biology across development.

Household Chaos Moderates Indirect Pathways Involving Domestic Violence, Parenting Practices, and Behavior Problems among Preschool Children

PURPOSE

This study examined the moderating role of household chaos in indirect pathways involving domestic violence (DV), parenting practices (punitive discipline and responsive), and preschool children's internalizing and externalizing symptoms. We hypothesized that high levels of household chaos would amplify links between domestic violence and parenting difficulties, and that parenting difficulties would in turn predict child behavior problems.

METHOD

Participants in this multimethod (survey, semi-structured interview, child protection records) study included 274 preschool children (M _age = 50.86 months) and their primary caregivers who were assessed in the home at two time-points spaced 6 months apart. Child welfare documentation of moderate-severe maltreatment within the last 6 months was present for 52% of children, 44% were in households characterized by DV, and most families qualified for public assistance. Hypotheses were tested using path analysis with manifest variables within a structural equation modeling framework.

RESULTS

All models provided excellent fit to the data. DV was associated with punitive discipline practices only when household chaos was high. Punitive discipline practices in turn predicted greater child externalizing symptoms 6 months later. Follow-up analyses revealed that the moderating role of chaos was specific to DV, rather than general to other forms of adversity (child maltreatment, lifetime contextual stressors, traumatic events). This interaction between DV and chaos was salient even when controlling for exposure to other adversities and demographic covariates.

CONCLUSIONS

Results point to multiple potential targets of intervention that may ultimately buffer children from the risk posed by experiencing DV in the home.

Molecular markers of neuroendocrine function and mitochondrial biogenesis associated with early life stress

OBJECTIVE

Glucocorticoid receptor gene (NR3C1) promoter methylation influences cellular expression of the glucocorticoid receptor and is a proposed mechanism by which early life stress impacts neuroendocrine function. Mitochondria are sensitive and responsive to neuroendocrine stress signaling through the glucocorticoid receptor, and recent evidence with this sample and others shows that mitochondrial DNA copy number (mtDNAcn) is increased in adults with a history of early stress. No prior work has examined the role of NR3C1 methylation in the association between early life stress and mtDNAcn alterations.

METHODS

Adult participants (n = 290) completed diagnostic interviews and questionnaires characterizing early stress and lifetime psychiatric symptoms. Medical conditions, active substance abuse, and prescription medications other than oral contraceptives were exclusionary. Subjects with a history of lifetime bipolar, obsessive-compulsive, or psychotic disorders were excluded; individuals with other forms of major psychopathology were included. Whole blood mtDNAcn was measured using qPCR; NR3C1 methylation was measured via pyrosequencing. Multiple regression and bootstrapping procedures tested NR3C1 methylation as a mediator of effects of early stress on mtDNAcn.

RESULTS

The positive association between early adversity and mtDNAcn (p = .02) was mediated by negative associations of early adversity with NR3C1 methylation (p = .02) and NR3C1 methylation with mtDNAcn (p < .001). The indirect effect involving early adversity, NR3C1 methylation, and mtDNAcn was significant (95 % CI [.002, .030]).

CONCLUSIONS

NR3C1 methylation significantly mediates the association between early stress and mtDNAcn, suggesting that glucocorticoid receptor signaling may be a mechanistic pathway underlying mtDNAcn alterations of interest for future longitudinal work.

Sex Differences in Associations between Early Adversity, Child Temperament, and Behavior Problems

Early adversity is associated with both internalizing and externalizing problems among children, and effects of adversity on dimensions of child temperament may underlie these links. However, very little is known about the role of child sex in these processes. The current study examined if there are indirect effects of early adversity on behavior problems through dimensions of child temperament and if these indirect effects vary across child sex. Participants in this multimethod (parent-report survey, semi-structured interview, child protection records) study included 274 preschool-aged children (M _age = 50.86 months; 52% with documented case of moderate-severe maltreatment) and their primary caregivers assessed at two time-points spaced 6 months apart. Results of multi-group path analyses revealed that while anger mediated associations between lifetime stress and behavior problems for the full sample, inhibitory control and appropriate attentional allocation were significant intermediary mechanisms of lifetime stress for boys, but not for girls. Inhibitory control mediated associations between maltreatment and behavior problems for the full sample, but appropriate attentional allocation mediated these associations for boys only. Results suggest that early adversity influences child behavior problems through child temperament, particularly for boys. This work supports the perspective that temperament is influenced by characteristics of the early rearing environment, and the indirect effects of adversity on behavior problems through temperament vary across sex.

Infant sleep moderates the effect of infant temperament on maternal depressive symptoms, maternal sensitivity, and family functioning

Observed infant temperamental difficulty and infant sleep efficiency and sleep variability were examined as predictors of maternal depressive symptoms, maternal sensitivity, and family functioning. Eight observations at 8-months postpartum were used to assess infant temperament, and actigraphy was used to measure infant sleep for 1-week at the time of the 8-month assessment. Structured clinical interviews were used to assess maternal depressive symptoms between 5 and 12 months postpartum and at 15 months postpartum, and observational assessments were used to assess maternal sensitivity and family functioning at 15 months postpartum. Variability in infant sleep moderated the effect of infant temperament on maternal depressive symptoms, maternal sensitivity, and family functioning. Infant temperament was positively associated with maternal depressive symptoms when variability in infant sleep efficiency was high, but not when variability in infant sleep efficiency was low. Likewise, infant temperament was negatively associated with maternal sensitivity and family functioning when variability in infant sleep efficiency was high, but not when variability in infant sleep efficiency was low. Results underscore the importance of infant sleep for maternal and family health.

Childhood maltreatment, behavioral adjustment, and molecular markers of cellular aging in preschool-aged children: A cohort study

OBJECTIVE

Childhood maltreatment is a major risk factor for the development of behavioral problems and poor physical and mental health. Accelerated cellular aging, through reduced telomere length and mitochondrial dysfunction, may be a mechanism underlying these associations.

METHODS

Families with (n = 133) and without (n = 123) child welfare documentation of moderate-severe maltreatment in the past six months participated in this study. Children ranged in age from 3 to 5 years, were racially and ethnically diverse, and 91% qualified for public assistance. Structured record review and interviews were used to assess a history of maltreatment and other adversities. Telomere length and mitochondrial DNA copy number (mtDNAcn) were measured from saliva DNA using real-time PCR. Measures were repeated at a six-month follow-up assessment. Repeated measures general linear models were used to examine the effects of maltreatment and other adversities on telomere length and mtDNAcn over time.

RESULTS

Maltreatment and other adverse experiences were significant positive predictors of both telomere length and mtDNAcn over time. Internalizing and externalizing behavior problems were also both significantly associated with telomere length, but only internalizing symptoms were associated with mtDNAcn.

CONCLUSIONS

This is the first study to show that mtDNAcn is altered in children with stress and trauma, and the findings are consistent with recent studies of adults. Surprisingly, children who experienced moderate-severe levels of maltreatment in the prior six months had longer telomeres, possibly reflecting compensatory changes in response to recent trauma. Telomere length and mtDNAcn were also associated with behavioral problems, suggesting that these measures of cellular aging may be causally implicated in the pathophysiology of stress-related conditions.

Maternal witness to intimate partner violence during childhood and prenatal family functioning alter newborn cortisol reactivity

Witnessing intimate partner violence (IPV) during childhood is a risk factor for mental health problems across the lifespan. Less is known about the intergenerational consequences of witnessing IPV, and if the current family climate buffers intergenerational effects of witnessing violence. The mother's experience of witnessing IPV against her own mother during childhood, prenatal family dysfunction, and prenatal perceived stress were examined as predictors of offspring cortisol in the first month of life (N = 218 mother-infant dyads). Mothers reported on witnessing IPV in their childhoods, prenatal family dysfunction, and prenatal perceived stress in pregnancy. At 2 days and again at 1 month postpartum, infants engaged in a neurobehavioral exam to assess infant cortisol reactivity. Infants whose mothers witnessed IPV in childhood exhibited alterations in their baseline cortisol and their cortisol reactivity at 1 month of age, whereas family dysfunction during pregnancy was associated with baseline cortisol and cortisol reactivity at 2 days of age. Prenatal perceived stress was not associated with infant cortisol at 2 days or 1 month. Prenatal family dysfunction and perceived stress did not moderate effects of the mother's experience of witnessing IPV. Results support the view that maternal experiences in childhood and during pregnancy exert intergenerational effects on the HPA stress response system.

Family Context Moderates the Association of Maternal Postpartum Depression and Stability of Infant Temperament

Maternal postpartum depression, maternal sensitivity, and family functioning were examined as predictors of the stability of observed infant temperament over the first 30 months of life (N = 147 families). Eight observations at 8, 15, and 30 months postpartum were used to assess infant temperament. Structured clinical interviews were used to assess maternal depression, and observational assessments were used to assess family functioning and maternal sensitivity. Family context moderated the effect of maternal depression on change in infant temperament. Maternal depression was associated with change in infant temperament when maternal sensitivity was low but not when maternal sensitivity was high. Family functioning similarly moderated these links. Results underscore the centrality of the family context in shaping child behavior over time.

Dynamic stress-related epigenetic regulation of the glucocorticoid receptor gene promoter during early development: The role of child maltreatment

Epigenetics processes may play a vital role in the biological embedding of early environmental adversity and the development of psychopathology. Accumulating evidence suggests that maltreatment is linked to methylation of the glucocorticoid receptor gene, nuclear receptor subfamily 3, group C, member 1 (NR3C1), which is a key regulator of the hypothalamus-pituitary-adrenal axis. However, prior work has been exclusively cross-sectional, greatly constraining our understanding of stress-related epigenetic processes over time. In the current study, we examined the effect of maltreatment and other adversity on change in NR3C1 methylation among at-risk preschoolers to begin to characterize within-child epigenetic changes during this sensitive developmental period. Participants were 260 preschoolers (3-5 years old, 53.8% female), including 51.5% with moderate to severe maltreatment in the past 6 months. Child protection records, semistructured interviews, and parent reports were used to assess child stress exposure. Methylation of exons 1D and 1F of NR3C1 via saliva DNA were measured at two time points approximately 6 months apart. Results indicate that maltreated children evidence higher baseline levels of NR3C1 methylation, significant decreases in methylation over time, and then at follow-up, lower levels of methylation, relative to nonmaltreated preschoolers. Findings from the current study highlight the complex nature of stress-related epigenetic processes during early development.

Prenatal Major Depressive Disorder, Placenta Glucocorticoid and Serotonergic Signaling, and Infant Cortisol Response

OBJECTIVES

Extending prior studies of prenatal adversity and depressive symptoms, we tested associations between maternal prenatal major depressive disorder (MDD) and infant cortisol regulation. Based on prior findings by our group, we also tested placenta glucocorticoid (HSD11B2 methylation) and serotonin (SLC6A4 gene expression) signaling as moderators of links between prenatal MDD and infant cortisol.

METHODS

Participants were 153 mother-infant pairs from a low-income, diverse sample (M [SD] age = 26 [6] years). Repeated structured diagnostic interviews were used to identify mothers with (a) prenatal MDD, (b) preconception-only MDD, and (c) controls. Placenta samples were assayed for HSD11B2 methylation and SLC6A4 gene expression. Infant salivary cortisol response to a neurobehavioral examination was assessed at 1 month.

RESULTS

Daughters of prenatal MDD mothers had 51% higher baseline (ratio = 1.51; 95% confidence interval [CI] = 1.01-2.27; p = .045) and 64% higher stress responsive cortisol (ratio = 1.64; 95% CI = 1.05-2.56; p = .03) than daughters of controls and 75% higher stress-responsive cortisol (ratio = 1.75; 95% CI = 1.04-2.94; p = .04) than daughters of preconception-only MDD mothers. HSD11B2 methylation moderated links between prenatal MDD and baseline cortisol (p = .02), with 1% methylation decreases associated with 9% increased baseline cortisol in infants of prenatal MDD mothers (ratio = 1.09; 95% CI = 1.01-1.16). SLC6A4 expression moderated links between prenatal MDD and cortisol response among boys alone (p = .007), with 10-fold increases in expression associated with threefold increases in stress-responsive cortisol (ratio = 2.87; 95% CI = 1.39-5.93) in sons of control mothers.

CONCLUSIONS

Results highlight specificity of associations between prenatal versus preconception MDD and cortisol regulation and the importance and complexity of placenta glucocorticoid and serotonergic pathways underlying the intergenerational transmission of risk from maternal adversity.

Methylation of the Glucocorticoid Receptor Gene Promoter in Preschoolers: Links With Internalizing Behavior Problems

Accumulating evidence suggests that early adversity is linked to methylation of the glucocorticoid receptor (GR) gene, NR3C1, which is a key regulator of the hypothalamic-pituitary-adrenal axis. Yet no prior work has considered the contribution of methylation of NR3C1 to emerging behavior problems and psychopathology in childhood. This study examined the links between methylation of NR3C1 and behavior problems in preschoolers. Data were drawn from a sample of preschoolers with early adversity (n = 171). Children ranged in age from 3 to 5 years, were racially and ethnically diverse, and nearly all qualified for public assistance. Seventy-one children had child welfare documentation of moderate to severe maltreatment in the past 6 months. Structured record review and interviews in the home were used to assess early adversity. Parents reported on child internalizing and externalizing behavior problems. Methylation of NR3C1 at exons 1D , 1F , and 1H were measured via sodium bisulfite pyrosequencing from saliva DNA. Methylation of NR3C1 at exons 1D and 1F was positively associated with internalizing (r = .21, p < .01 and r = .23, p < .01, respectively), but not externalizing, behavior problems. Furthermore, NR3C1 methylation mediated effects of early adversity on internalizing behavior problems. These results suggest that methylation of NR3C1 contributes to psychopathology in young children, and NR3C1 methylation from saliva DNA is salient to behavioral outcomes.

Goodness of fit between prenatal maternal sleep and infant sleep: Associations with maternal depression and attachment security

The current study prospectively examined the ways in which goodness of fit between maternal and infant sleep contributes to maternal depressive symptoms and the mother-child relationship across the first years of life. In a sample of 173 mother-child dyads, maternal prenatal sleep, infant sleep, maternal depressive symptoms, and mother-child attachment security were assessed via self-report, actigraphy, and observational measures. Results suggested that a poor fit between mothers' prenatal sleep and infants' sleep at 8 months (measured by sleep diary and actigraphy) was associated with maternal depressive symptoms at 15 months. Additionally, maternal depression mediated the association between the interplay of mother and infant sleep (measured by sleep diary) and mother-child attachment security at 30 months. Findings emphasize the importance of the match between mother and infant sleep on maternal wellbeing and mother-child relationships and highlight the role of mothers' perceptions of infant sleep.

Alterations of Mitochondrial DNA Copy Number and Telomere Length With Early Adversity and Psychopathology

BACKGROUND

Telomere shortening and alterations of mitochondrial biogenesis are involved in cellular aging. Childhood adversity is associated with telomere shortening, and several investigations have shown short telomeres in psychiatric disorders. Recent studies have examined whether mitochondria might be involved in neuropsychiatric conditions; findings are limited and no prior work has examined this in relation to stress exposure.

METHODS

Two-hundred ninety healthy adults provided information on childhood parental loss and maltreatment and completed diagnostic interviews. Participants were categorized into four groups based upon the presence or absence of childhood adversity and the presence or absence of lifetime psychopathology (depressive, anxiety, and substance use disorders). Telomere length and mitochondrial DNA (mtDNA) copy number were measured from leukocyte DNA by quantitative polymerase chain reaction.

RESULTS

Childhood adversity and lifetime psychopathology were each associated with shorter telomeres (p < .01) and higher mtDNA copy numbers (p < .001). Significantly higher mtDNA copy numbers and shorter telomeres were seen in individuals with major depression, depressive disorders, and anxiety disorders, as well as those with parental loss and childhood maltreatment. A history of substance disorders was also associated with significantly higher mtDNA copy numbers.

CONCLUSIONS

This study provides the first evidence of an alteration of mitochondrial biogenesis with early life stress and with anxiety and substance use disorders. We replicate prior work on telomere length and psychopathology and show that this effect is not secondary to medication use or comorbid medical illness. Finally, we show that early life stress and psychopathology are each associated with these markers of cellular aging.

Stability of child behavioral style in the first 30 months of life

The current study examined the stability of temperament over time. Observers and mothers rated child behavior at eight timepoints across three assessment waves (8, 15, and 30 months of age). Internal consistency reliability of aggregates of the eight observer reports and eight mother reports were high. When considering single timepoint assessments, stability of temperament between assessment waves was generally low to moderate in magnitude. When the eight observations were aggregated, rather than when single timepoints were considered, between-wave stability of temperament increased. Mother reports of temperament were generally more stable than observer reports. Results have important methodological implications and suggest multiple observations of child behavior within a single developmental period are necessary to evaluate the stability of temperament over time.

Infant development in family context: call for a genetically informed approach

We call for a genetically informed approach in the examination of infant social and emotional development in family context. We recommend that scholars conceptualize family functioning as occurring on three unique levels: the parent-child dyad, the inter-parental dyad, and whole family functioning. Although advances in the area of understanding genetic variation in infants as a potential moderator of the influence of parent-child dyadic functioning have been made over the past decade, it is time to widen this inquiry to consider genetic variation in infants as a potential moderator of the influence of inter-parental dyadic and whole family functioning as well. A critical review of the literature also calls for additional examination of genetic variation in infants as a moderator of positive contextual influences, the integration of unique temperament variables with studies of infant genotype, consideration of the role of the gene-environment correlation, and epigenetic effects. Furthermore, we call for the application of genetically-informed research methods to these questions. Expanding knowledge in this area has the potential to refine treatment and prevention efforts aimed at promoting infant social and emotional development.

Mothers' emotional reactions to crying pose risk for subsequent attachment insecurity

Links between maternal emotional reactions to crying (anger and anxiety) and infant attachment security were examined in 119 mother-infant dyads. Mothers rated the intensity of their emotional responses to videotapes of crying infants prenatally. Maternal sensitivity was observed during infant exposure to emotion eliciting tasks at six and 16 months postpartum and mothers' self-reported on their responses to their infant's negative emotions at 16 months. Infant attachment security was assessed using the Strange Situation at 16 months postpartum. Results indicated that observed sensitivity was associated with fewer avoidant and resistant behaviors and prenatal maternal anger and anxiety in response to infant crying predicted the developing attachment system independent of observed sensitivity, but in different ways. Maternal anxiety in response to crying was positively associated with resistant behaviors as a direct effect. Maternal anger in response to crying was associated with avoidant behaviors indirectly through mothers' self-reported punitive and minimizing responses to infant distress at 16 months. Theoretical, applied, and methodological implications are discussed.

Marital aggression predicts infant orienting toward mother at six months

Links between marital aggression and infant orienting toward mother in fearful and frustrating contexts were examined in 92 mother-infant dyads when infants were six months. Results demonstrated that marital aggression was linked with less orienting toward mothers in frustrating situations, in fearful situations marital aggression was linked with less orienting among infants who were high on fear reactivity only.

Origins of Mothers' and Fathers' Beliefs about Infant Crying

Origins of mothers' and fathers' beliefs about infant crying were examined in 87 couples. Parents completed measures of emotion minimization in the family of origin, depressive symptoms, empathy, trait anger, and coping styles prenatally. At 6 months postpartum, parents completed a self-report measure of their beliefs about infant crying. Mothers endorsed more infant-oriented and less parent-oriented beliefs about crying than did fathers. Consistent with prediction, a history of emotion minimization was linked with more parent-oriented and fewer infant-oriented beliefs about infant crying for both mothers and fathers either as a main effect or in conjunction with the partners' infant-oriented beliefs. Contrary to expectation, parents' own emotional dispositions had little effect on parents' beliefs about crying. The pattern of associations varied for mothers and fathers in a number of ways. Implications for future research and programs promoting sensitive parenting are discussed.

The reliability and validity of the Infant Behavior Questionnaire-Revised

The reliability and validity of the Infant Behavior Questionnaire-Revised was examined in a sample of 6-month-old infants and their parents. One hundred and fifteen mothers and 79 fathers completed the IBQ-R and a measure of depression and 98 infants participated in a laboratory assessment of temperament. Internal consistency reliability was adequate for all 14 IBQ-R subscales for both mothers and fathers and inter-rater reliability of mother and father reports was demonstrated for 11 of 14 subscales. Convergent validity was established between observed fear and mother reported fear and father reported approach. Parent depression and infant gender were examined as moderators of the concordance between parent reported and observed temperament. As predicted, concordance was higher when parents reported low versus high symptoms of depression. Infant gender did not alter concordance.