Neglectful maternal caregiving involves altered brain volume in empathy-related areas

Mother adversity and co-residence time impact mother-child similarity in genome-wide and gene-specific methylation profiles

BACKGROUND

The effects of adverse life events on physical and psychological health, with DNA methylation (DNAm) as a critical underlying mechanism, have been extensively studied. However, the epigenetic resemblance between mother and child in the context of neglectful caregiving, and whether it may be shaped by the emotional impact of maternal stressful events and the duration of co-residence (indexed by child age), remains unknown. The present study examined mother-child similarity in methylation profiles, considering the potential effect of mother adversity, mother empathy, neglect-control group, child age (an index of years of mother-child co-residence), and mother age. Using Illumina Epic arrays, we quantified DNAm in 115 mother-child saliva samples. We obtained a methylation similarity index by computing correlation coefficients between methylation profiles within dyads, for the entire epigenome, and five specific genes related to stress and empathy: NR3C1, FKPB5, OXTR, SCL6A4, and BDNF.

RESULTS

The methylation profiles of the mother-child familial pairs significantly correlated as compared to mother-child random pairs for the entire epigenome and NR3C1, FKBP5, OXTR and BDNF genes. Next, multiple linear regression models observed associations of mother adversity, child age, and neglect-control group on mother-child methylation similarity, only significant in mother-child familial pairs, after correcting for multiple comparisons. Higher mother adversity was associated with lower mother-child methylation similarity for the epigenome-wide analysis, for the BDNF gene, and in the neglect-control group for the OXTR gene. In turn, being an older child (longer co-residence) was associated with higher mother-child methylation similarity.

CONCLUSIONS

Mother adversity and co-residence time are modulating factors in the intergenerational methylation process that offer a window into development-dependent adaptations that can be affected by both hereditary and environmental factors, significantly observed only in biological dyads. A twofold implication for child well-being emerges, one is positive in that children of mothers exposed to life adversity or neglect did not necessarily inherit their methylation patterns. The other is concerning due to the influence of time spent living together, which affects similarity with the mother and potentially increases the risk of inheriting an epigenetic profile associated with future dysfunctional parenting patterns. This underscores the importance of the 'the earlier, the better' recommendation by the Child Protection System, which is not always followed.

Diffusion tensor imaging of white-matter structural features of maltreating mothers and their associations with intergenerational chain of childhood abuse

Child abuse causes lifelong adverse outcomes for both physical and mental health, although many are resilient. Efforts to prevent this issue from the parental side require an understanding of the neurobiological basis that leads abusive parents to perpetrate abuse and the influence of the intergenerational chain of childhood abuse. Therefore, this study was conducted to compare the brain white-matter fiber structures between 11 maltreating mothers who had been recognized as having conducted child abuse prior to the intervention and 40 age-matched control mothers using tract-based spatial statistics. There was a significantly reduced axial diffusivity (AD) and a similar trend in fractional anisotropy (FA) in the right corticospinal tract in maltreating mothers compared to control mothers. Therefore, maltreating mothers may have excessive control over the forcefulness of voluntary movements. These features also decreased as the number of childhood abuse experiences increased, suggesting that an intergenerational chain of child abuse may also be involved. Other aspects observed were that the higher the current depressive symptoms, the lower the AD and FA values; however, they were not related to parental practice or empathy. These results corroborate the neurobiological features that perpetrate behaviors in abusive mothers.

The development of empathy in child maltreatment contexts

BACKGROUND

Despite robust associations between child maltreatment experiences and emotional development, a paucity of research examines the influence of child maltreatment on empathy development, and still fewer studies differentiate these effects across maltreatment subtypes.

OBJECTIVE

The present study examined the development of children's empathy from ages six to eight, as predicted by maltreatment, and as moderated by children's attachment representations.

PARTICIPANTS AND SETTING

Participants were a community sample of 250 children followed longitudinally and assessed in a laboratory setting with their primary caregivers.

METHOD

Child maltreatment experiences from birth to age six were assessed by semi-structured interviews with caregivers, which were rated according to widely-used child maltreatment coding protocols, and by caregiver and child self-report measures. Child empathy was assessed at ages six and eight by caregiver-report. Attachment representations were observed in children using the MacArthur Story Stem Battery.

RESULTS

Child emotional abuse (β = -0.150, p = .012) and child neglect (β = -0.137, p = .016) predicted decreased empathy at age eight, whereas child physical abuse (β = 0.132, p = .027) and child exposure to domestic violence (β = 0.164, p = .004) predicted increased empathy at age eight. Further, children's negative representations of mother figures moderated the positive association between child physical abuse and empathy (β = -0.177, p = .005), such that the association became weaker as negative representations increased.

CONCLUSIONS

These results highlight the nuanced ways in which child maltreatment experiences of different subtypes contribute to the development of empathy in school-aged children.

The shared mother-child epigenetic signature of neglect is related to maternal adverse events

Studies of DNA methylation have revealed the biological mechanisms by which life adversity confers risk for later physical and mental health problems. What remains unknown is the “biologically embedding” of maternal adverse experiences resulting in maladaptive parenting and whether these epigenetic effects are transmitted to the next generation. This study focuses on neglectful mothering indexed by a severe disregard for the basic and psychological needs of the child. Using the Illumina Human Methylation EPIC BeadChip in saliva samples, we identified genes with differentially methylated regions (DMRs) in those mothers with (n = 51), versus those without (n = 87), neglectful behavior that present similar DMRs patterns in their children being neglected versus non-neglected (n = 40 vs. 75). Mothers reported the emotional intensity of adverse life events. After covariate adjustment and multiple testing corrections, we identified 69 DMRs in the mother epigenome and 42 DMRs in the child epigenome that were simultaneously above the α = 0.01 threshold. The common set of nine DMRs contained genes related to childhood adversity, neonatal and infant diabetes, child neurobehavioral development and other health problems such as obesity, hypertension, cancer, posttraumatic stress, and the Alzheimer’s disease; four of the genes were associated with maternal life adversity. Identifying a shared epigenetic signature of neglect linked to maternal life adversity is an essential step in breaking the intergenerational transmission of one of the most common forms of childhood maltreatment.

Reduction in Epigenetic Age Acceleration Is Related to Empathy in Mothers with Neglectful Caregiving

DNA methylation clocks are used as molecular estimators of epigenetic age, but with little evidence in mothers and none in neglectful mothering. We investigated differences in epigenetic age acceleration (EAA) and the role of empathy using the PhenoAge clock. We collected saliva samples from mothers with extreme disregard for their child's needs (50 in the neglect group, NG) and mothers with non-neglectful caregiving (87 in the control group, CG). Mothers completed an empathy scale, along with questionnaires of their own childhood maltreatment, adverse life events and psychiatric disorders. Sociodemographic variables potentially affecting EAA were also measured. The ANCOVA solution showed a significant increase in EAA in the NG compared to the CG, after adjustment for maternal age, number of pregnancies, financial assistance, adverse events, childhood maltreatment and psychiatric disorder. The group interaction effects showed a reduction in EAA for greater empathic concern and for a higher education level both as positive factors, and an increment in EAA for mothers living in a two-parent family as a risk factor, all in the NG. Our findings open the search for protective factors of EAA associated with caregiver behavior to reduce health vulnerabilities and poor social functioning, especially for mothers at risk of maladaptive caregiving.

Improving Early Diagnosis of Child Neglect for a Better Response in Healthcare Settings

Early diagnosis of child neglect is an ongoing challenge with consequences of the child’s safety, health, and effective referral for intervention. This study aims to obtain a selected set of family, maternal, and dyadic variables of the immediate caregiving environment for diagnosis, preventive, and intervention responses in healthcare settings. Mothers and their children under five years old: 51 in the neglected group (NG) and 89 in the non-neglected control group (CG), were recruited through pediatric primary care services and social services in Spain. Family demographics, adverse events, childhood maltreatment, maternal psychopathologies, personality variables, and observed mother–child interactions were assessed. Gradient boosting analyses were applied for the contributor’s relative importance (RI), followed by logistic regression and discriminant analyses for those with higher RI. Parametric analyses showed high diagnostic accuracy (80–82% of NG and 92% of CG) for risky factors of child neglect: having a physically neglected and depressed mother, living in families in need of financial assistance, and large families; and for protective factors: having an older mother and showing higher mother–child emotional availability. Identifying a select group of features makes early diagnosis and preventive intervention more effective for mitigating the impact of child neglect and building mother–child resilience.

Neurobiological Implications of Parent-Child Emotional Availability: A Review

Parental influences are important for a child's behavior, overall adjustment, as well as cognitive/language development. New research is exploring how relationships with parents can influence a child's neurobiological functioning and development. In this systematic review, our first aim is to describe how the caregiving environment influences these aspects of child development. The second and main aim is to review and recommend that the concept (and measurement) of "emotional availability" may provide a new window in this continued exploration. Emotional availability (EA) refers to the capacity of a dyad to share an emotionally healthy relationship. The EA Scales assess this construct using a multi-dimensional framework, with a method to measure the affect and behavior of both the child and adult partner (caregiver). In this review, we first provide an overview of child development research, with regards to stress physiology, neuroendocrine system, genetics and epigenetics, and brain mechanisms. We then summarize the results of specific EA research in these areas, and propose a theoretical model integrating these constructs. Finally, we offer areas for future research in this area.

Distinctive Frontal and Occipitotemporal Surface Features in Neglectful Parenting

Although the brain signatures of adaptive human parenting are well documented, the cortical features associated with maladaptive caregiving are underexplored. We investigated whether cortical thickness and surface area vary in a small group of mothers who had neglected their children (24 in the neglect group, NG) compared to a control group of mothers with non-neglectful caregiving (21 in the control group, CG). We also tested whether the cortical differences were related to dyadic mother-child emotional availability (EA) in a play task with their children and whether alexithymia involving low emotional awareness that characterizes the NG could play a role in the cortical-EA associations. Whole-brain analysis of the cortical mantle identified reduced cortical thickness in the right rostral middle frontal gyrus and an increased surface area in the right lingual and lateral occipital cortices for the NG with respect to the CG. Follow-up path analysis showed direct effects of the right rostral middle frontal gyrus (RMFG) on the emotional availability (EA) and on the difficulty to identify feelings (alexithymia factor), with a marginal indirect RMFG-EA effect through this factor. These preliminary findings extend existing work by implicating differences in cortical features associated with neglectful parenting and relevant to mother-child interactive bonding.