The effect of a maternal history of childhood abuse on adrenocortical attunement in mothers and their toddlers

Maternal History of Adversity and Subsequent Mother-Child Interactions at Early Ages: A Systematic Review

Adverse childhood experiences (ACEs) can negatively impact physical, emotional, cognitive, and social development, consequently affecting the next generation. The aim of the present study was to systematically review evidence from empirical studies on the association between maternal history of adversity in childhood (maltreatment and household dysfunction) and subsequent mother-child interactions at an early age. A search was performed in the PubMed, Web of Science, PsycINFO, EMBASE, Scopus, LILACS, and SciELO databases to identify studies, including measures of maternal childhood adversities and mother-child interaction, published between 2016 and 2022. Twenty-nine studies met the inclusion criteria. The results showed that in 90% of the studies, maternal childhood adversities negatively impacted subsequent mother-child interactions in early childhood, reducing maternal displays of affection, emotional availability, sensitivity, mother-child communication, and bonding. Biological factors (e.g., genetic and hormonal) and maternal emotional recognition moderated these associations. In addition, biological factors (i.e., neurobiological and hormonal) and psychosocial factors (e.g., depression, executive functioning, and violence) acted as mediators. Preventive interventions should be implemented to break out of the intergenerational cycle of violence that impacts mother-child interactions.

Maternal Childhood Maltreatment Is Associated With Lower Infant Gray Matter Volume and Amygdala Volume During the First Two Years of Life

Background

Childhood maltreatment affects approximately 25% of the world's population. Importantly, the children of mothers who have been maltreated are at increased risk of behavioral problems. Thus, one important priority is to identify child neurobiological processes associated with maternal childhood maltreatment (MCM) that might contribute to such intergenerational transmission. This study assessed the impact of MCM on infant gray and white matter volumes and infant amygdala and hippocampal volumes during the first 2 years of life.

Methods

Fifty-seven mothers with 4-month-old infants were assessed for MCM, using both the brief Adverse Childhood Experiences screening questionnaire and the more detailed Maltreatment and Abuse Chronology of Exposure scale. A total of 58% had experienced childhood maltreatment. Between 4 and 24 months (age in months: mean = 12.28, SD = 5.99), under natural sleep, infants completed a magnetic resonance imaging scan using a 3T Siemens scanner. Total brain volume, gray matter volume, white matter volume, and amygdala and hippocampal volumes were extracted via automated segmentation.

Results

MCM on the Adverse Childhood Experiences and Maltreatment and Abuse Chronology of Exposure scales were associated with lower infant total brain volume and gray matter volume, with no moderation by infant age. However, infant age moderated the association between MCM and right amygdala volume, such that MCM was associated with lower volume at older ages.

Conclusions

MCM is associated with alterations in infant brain volumes, calling for further identification of the prenatal and postnatal mechanisms contributing to such intergenerational transmission. Furthermore, the brief Adverse Childhood Experiences questionnaire predicted these alterations, suggesting the potential utility of early screening for infant risk.

Intergenerational neuroimaging study: mother-infant functional connectivity similarity and the role of infant and maternal factors

Mother and infant neural and behavioral synchrony is important for infant development during the first years of life. Recent studies also suggest that neural risk markers associated with parental psychopathology may be transmitted across generations before symptoms emerge in offspring. There is limited understanding of how early similarity in brain functioning between 2 generations emerges. In the current study, using functional magnetic resonance imaging, we examined the functional connectivity (FC) similarity between mothers and newborns during the first 3 months after the infant's birth. We found that FC similarity between mothers and infants increased as infant age increased. Furthermore, we examined whether maternal factors such as maternal socioeconomic status and prenatal maternal depressive symptoms may influence individual differences in FC similarity. For the whole-brain level, lower maternal education levels were associated with greater FC similarity. In previous literature, lower maternal education levels were associated with suboptimal cognitive and socioemotional development. Greater FC similarity may reflect that the infants develop their FC similarity prematurely, which may suboptimally influence their developmental outcomes in later ages.

Child maltreatment and hypothalamic-pituitary-adrenal axis functioning: A systematic review and meta-analysis

Alterations in hypothalamic-pituitary-adrenal (HPA) axis and its effector hormone cortisol have been proposed as one possible mechanism linking child maltreatment experiences to health disparities. In this series of meta-analyses, we aimed to quantify the existing evidence on the effect of child maltreatment on various measures of HPA axis activity. The systematic literature search yielded 1,858 records, of which 87 studies (k = 132) were included. Using random-effects models, we found evidence for blunted cortisol stress reactivity in individuals exposed to child maltreatment. In contrast, no overall differences were found in any of the other HPA axis activity measures (including measures of daily activity, cortisol assessed in the context of pharmacological challenges and cumulative measures of cortisol secretion). The impact of several moderators (e.g., sex, psychopathology, study quality), the role of methodological shortcomings of existing studies, as well as potential directions for future research are discussed.

Maternal Interaction With Infants Among Women at Elevated Risk for Postpartum Depression

Ample research links mothers' postpartum depression (PPD) to adverse interactions with their infants. However, most studies relied on general population samples, whereas a substantial number of women are at elevated depression risk. The purpose of this study was to describe mothers' interactions with their 6- and 12-month-old infants among women at elevated risk, although with a range of symptom severity. We also identified higher-order factors that best characterized the interactions and tested longitudinal consistency of these factors from 6 to 12 months of infant age. We leveraged data from eight projects across the United States (n = 647), using standardized depression measures and an adaptation of the NICHD Mother-Infant Interaction Scales. Overall, these depression-vulnerable mothers showed high levels of sensitivity and positive regard and low levels of intrusiveness, detachment, and negative regard with their infants. Factor analyses of maternal behaviors identified two overarching factors-"positive engagement" and "negative intrusiveness" that were comparable at 6 and 12 months of infant age. Mothers' ability to regulate depressed mood was a key behavior that defined "positive engagement" in factor loadings. An exceptionally strong loading of intrusiveness on the second factor suggested its central importance for women at elevated depression risk. Mothers with severe depressive symptoms had significantly more "negative intrusiveness" and less "positive engagement" with their 6-month-old infants than women with moderate or fewer depressive symptoms, suggesting a potential tipping point at which symptoms may interfere with the quality of care. Results provide the foundation for further research into predictors and moderators of women's interactions with their infant among women at elevated risk for PPD. They also indicate a need for evidence-based interventions that can support more severely depressed women in providing optimal care.

Parental history of childhood maltreatment and child average RSA shape parent-child RSA synchrony

We examined whether dynamic parent-child RSA synchrony varied by individual differences in child average RSA and parental history of childhood maltreatment (CM), which has been linked to parental behavioral and physiological dysregulation. We also examined whether RSA synchrony was curvilinear, reflecting homeostatic regulation. Synchrony was defined as the dynamic association between parent and child RSA reactivity (change relative to their own mean) within epoch across a challenging task. Eighty-three mother-preschooler and 61 father-preschooler dyads participated. State-trait modeling showed that RSA synchrony was curvilinear such that significant relations were only found at lower and higher child reactivity. Children's higher task average RSA predicted maternal RSA augmentation and lower task average RSA predicted maternal RSA withdrawal, regardless of whether child reactivity in the moment was low or high, suggesting individual differences in child regulatory capacity were associated with dynamic maternal reactivity. When maternal CM history and child average RSA were both higher, mothers showed RSA augmentation. Father-child synchrony was not moderated by child average RSA but greater paternal CM history predicted fathers' greater RSA withdrawal regardless of whether child RSA reactivity was low or high. Findings offer novel insights into the nature and meaning of RSA synchrony with parents at risk.

Individual differences in parent and child average RSA and parent psychological distress influence parent-child RSA synchrony

Parent-child synchrony of respiratory sinus arrhythmia (RSA) varies by risk, but novel approaches are needed to capture individual contributions to synchrony. Multilevel state-trait modeling was applied to examine how parental psychological distress and parent and child average RSA during challenge (reflecting individual regulatory capacities) shaped RSA synchrony in mother-child (n = 71) and father-child (n = 47) interactions. RSA synchrony was curvilinear such that greater in-the-moment RSA reactivity in one partner prompted greater reactivity in the other. Higher risk (lower average RSA; higher distress) predicted in-the-moment RSA withdrawal to partner RSA changes, whereas lower risk (higher average RSA; lower distress) predicted in-the-moment RSA augmentation. In some models, one's higher average RSA prompted the partner's greater reactivity and thus synchrony when parental distress was higher. However, the presence and direction of synchrony was not consistently adaptive nor maladaptive across models, suggesting its meaning relies on theory and the parent and risk factors in question.

Maternal experiences of childhood maltreatment moderate patterns of mother-infant cortisol regulation under stress

The relation between maternal and infant cortisol responses has been a subject of intense research over the past decade. Relatedly, it has been hypothesized that maternal history of childhood maltreatment (MCM) impacts stress regulation across generations. The current study employed four statistical approaches to determine how MCM influences the cortisol responses of 150 mothers and their 4-month-old infants during the Still-Face Paradigm. Results indicated that MCM moderated cortisol patterns in several ways. First, lower MCM mothers and infants had strong positive associations between cortisol levels measured at the same time point, whereas higher MCM mothers and infants did not show an association. Second, infants of higher MCM mothers had cortisol levels that were moderately high and remained elevated over the procedure, whereas infants of lower MCM mothers had decreasing cortisol levels over time. Third, higher MCM mothers and infants showed increasingly divergent cortisol levels over time, compared to lower MCM dyads. Finally, patterns of cross-lagged influence of infant cortisol on subsequent maternal cortisol were moderated by MCM, such that lower MCM mothers were influenced by their infants' cortisol levels at earlier time points than higher MCM mothers. These findings highlight MCM as one contributor to processes of stress regulation in the mother-infant dyad.

Maternal early life maltreatment and psychopathology affect the next generation: Alterations in post-awakening cortisol levels of primary school-aged children

Early life maltreatment (ELM) has severe and lasting effects on the individual, which might also impact the next generation. On an endocrine level, the hypothalamus-pituitary-adrenal axis has been suggested to play an important role in the interplay between ELM and the development of mental disorders. Several studies have revealed that maternal post-awakening cortisol concentration, maternal sensitivity, maternal ELM and psychopathology are associated with children's cortisol levels. We investigated the post-awakening cortisol concentrations in 6- to 11-year-old children (N = 53) whose mothers either had experienced ELM and had developed a lifetime mental disorder (N = 15 ELM and disorder group), had experienced ELM without developing a mental disorder (N = 12 ELM-only group), or had neither experienced ELM nor developed a mental disorder (N = 26 HC-group). Furthermore, we assessed maternal post-awakening cortisol concentrations, maternal psychopathology, and sensitivity. Multilevel analysis revealed higher cortisol at awakening (S1) levels in children of mothers with ELM and disorder. Maternal cortisol at awakening (S1) also predicted the child's cortisol at awakening (S1), and no effect of maternal sensitivity could be found. The current results replicate an attunement of cortisol levels (S1) between mothers and children and suggest an association between the children's endocrine stress system and maternal factors such as ELM and psychopathology.

Adolescents at risk of anxiety in interaction with their fathers: Studying non-verbal and physiological synchrony

Adolescence is a vulnerable period in terms of the onset of anxiety disorders, and dyadic parent-adolescent interactions may play a key role in either increasing or reducing the risk of psychopathologies. This study examines the presence of physiological synchrony (specifically, linkage in interbeat interval series) and non-verbal synchrony in positive and negative interactions between adolescents (aged 13-16) and their fathers. Non-verbal synchrony was quantified through the coordination of the interactants' body movements, using an automated video-analysis algorithm (motion energy analysis). Participants were made up of 53 parent-adolescent dyads, the latter at either low (n = 28) or high (n = 25) risk of anxiety. Adolescents at low risk of anxiety displayed statistically significant levels of non-verbal synchrony with their fathers during positive interactions. Non-verbal synchrony was not found in the father-adolescent dyads featuring adolescents at high risk of anxiety. Physiological synchrony was not significantly present above chance level in either of the groups of adolescents. Overall, the results suggest that adolescents at high risk of anxiety may have difficulties in managing non-distressing interactions with their fathers. The results also suggest that physiological synchrony is not a straightforward phenomenon.

Intimate partner violence indirectly dysregulates child diurnal adrenocortical functioning through positive parenting

Data were drawn from an ongoing study of preschoolers (N = 221). Mothers self-reported experiences of intimate partner violence (IPV) and parenting practices, and collected three saliva samples (waking, midday, and bedtime) on themselves and their child on 2 consecutive days. Saliva samples were later assayed for cortisol. Bootstrapped mediation analyses revealed IPV to indirectly impact child diurnal cortisol through positive parenting. Specifically, greater exposure to IPV was associated with reduced positive parenting and subsequently heightened child waking cortisol levels. IPV did not indirectly impact child diurnal cortisol via autonomy supporting parenting or maternal diurnal cortisol. These findings suggest a possible pathway by which mother's experience of IPV indirectly influences child physiological regulation via maternal positive parenting.

Intimate partner violence indirectly dysregulates child diurnal adrenocortical functioning through positive parenting

Data were drawn from an ongoing study of preschoolers (N = 221). Mothers self-reported experiences of intimate partner violence (IPV) and parenting practices, and collected three saliva samples (waking, midday, and bedtime) on themselves and their child on two consecutive days. Saliva samples were later assayed for cortisol. Bootstrapped mediation analyses revealed IPV to indirectly impact child diurnal cortisol through positive parenting. Specifically, greater exposure to IPV was associated with reduced positive parenting and subsequently heightened child waking cortisol levels. IPV did not indirectly impact child diurnal cortisol via autonomy supporting parenting or maternal diurnal cortisol. These findings suggest a possible pathway by which mother's experience of IPV indirectly influences child physiological regulation via maternal positive parenting.

Child Maltreatment and Mother-Child Transmission of Stress Physiology

In the current study, we examined the attunement and transmission of mother-child diurnal cortisol among maltreating (N = 165) and nonmaltreating (N = 83) mothers and their preschool-aged children. Over half of the families had a substantiated child maltreatment case with the mother as the perpetrator. Mothers collected three saliva samples (waking, midday, and bedtime) on themselves and their child on two consecutive days, which were later assayed for cortisol. This design allows for the examination of concurrent attunement, as well as cross-lagged transmission, across the day. Results from actor-partner interdependence models revealed significant differences in mother-child cortisol attunement and transmission between the maltreating and nonmaltreating groups. Specifically, only maltreating mothers transmitted cortisol to their children and were attuned at first waking; only nonmaltreating dyads were attuned at midday. Implications of these results for sociocultural models of stress physiology and for our understanding of how child maltreatment affects diurnal cortisol regulation are discussed.

Impact of maternal adverse childhood experiences on child socioemotional function in rural Kenya: Mediating role of maternal mental health

Mothers in low- and middle-income countries (LMIC) suffer heightened vulnerability for adverse childhood experiences (ACEs), which is exacerbated by the multitude of risk factors associated with poverty and may lead to increased risk of psychiatric disorder. The constellation of complex, co-occurring biological, environmental, social, economic and psychological risk factors are in turn transmitted to her child, conferring vulnerability for adverse development. This study examines the association between maternal intra- and extra-familial ACEs, maternal education and the mental health of her child, mediated by maternal mental health. Mother-child dyads (n = 121) in Machakos, Kenya were examined cross-sectionally using self-report measures of ACEs, maternal mental health and child internalizing and externalizing mental health problems. The four models proposed to examine the relationship between intra- and extra-familial maternal ACEs and child internalizing and externalizing problems demonstrated indirect pathways through maternal mental health. These effects were found to be conditional on levels of maternal education, which served as a protective factor at lower levels of maternal ACEs. These models demonstrate how the impact of ACEs persists across the lifespan resulting in a negative impact on maternal mental health and conferring further risk to subsequent generations. Elucidating the association between ACEs and subsequent intergenerational sequelae, especially in LMIC where risk is heightened, may improve targeted caregiver mental health programs for prevention and intervention.

A systematic review of parent-child synchrony: It is more than skin deep

This manuscript provides a critical review of the literature on parent-child physiological synchrony-the matching of biological states between parents and children. All eligible studies found some evidence of physiological synchrony, though the magnitude and direction of synchrony varied according to methodological factors, including the physiological system examined (i.e., parasympathetic or sympathetic nervous system activity, adrenocortical functioning) and the statistical approach used (e.g., multilevel modeling, correlation). The review underscores the need to consider the context in which physiological synchrony occurs (e.g., family risk) to best understand its significance. Furthermore, the review delineates vital avenues for future research, including the need to assess synchrony across multiple physiological systems and the importance of documenting continuity/change in physiological synchrony across developmental periods. Such research is crucial for understanding how the parent-child relationship unfolds at a physiological level and, in turn, how this relationship can facilitate or hinder parent, child, and family adjustment.