Revisiting the childcare-attachment question: under what conditions is childcare participation associated with mother-child attachment security?

Decades have passed since the controversy regarding the putative risks of childcare for mother-child attachment broke out. Yet, some uncertainty remains, as relevant studies have produced inconsistent evidence. Some have proposed that those conflicting findings may be due to the fact that the effects of childcare are conditioned on parenting. Accordingly, this study examined whether relations between childcare participation and mother-child attachment vary according to maternal sensitivity and autonomy support. In this sample of 236 mother-child dyads, there was no indication of main effects of childcare participation on attachment. There were, however, some interactive effects, such that the children who showed the least secure attachment behaviors were those who did not attend childcare and had either less sensitive or less autonomy-supportive mothers. The findings suggest that the effects of childcare on mother-child attachment are best understood in light of the parenting children receive at home.

From early birds to night owls: a longitudinal study of actigraphy-assessed sleep trajectories during the transition from pre- to early adolescence

STUDY OBJECTIVES

Pre- and early adolescence are believed to constitute periods of important age-related changes in sleep. However, much of the research on these presumed developmental changes has used cross-sectional data or subjective measures of sleep, limiting the quality of the evidence. In addition, little is known about the development of certain features of the sleep-wake cycle pertaining to regularity (e.g. weekend-weekday differences and intra-individual variability) or circadian rhythms (e.g. sleep midpoint).

METHODS

This study examined the sleep trajectories of 128 typically developing youth (69 girls) from ages 8 to 12 years on four sleep characteristics: sleep onset, sleep offset, total sleep time (TST), and sleep midpoint. For each of these characteristics, actigraphy-derived estimates of typical (i.e. mean) sleep and sleep regularity were obtained at each time point. Multilevel growth curves were modeled.

RESULTS

Overall, the sleep-wake cycle significantly changed between 8 and 12 years. Mean sleep onset, offset and midpoint exhibited an ascending curvilinear growth pattern that shifted later with age, while mean TST decreased linearly. Weekend-weekday differences (social jetlag) for sleep offset and midpoint became more pronounced each year. Weekday TST was longer than weekend TST, though this difference became smaller over time. Finally, intra-individual variability increased over time for all sleep characteristics, with variability in TST ascending curvilinearly. Important between-person and sex differences were also observed.

CONCLUSION

This study reveals the marked changes that occur in the sleep of typically developing pre- and early adolescents. We discuss the potential implications of these trajectories.

Longitudinal associations between the quality of family interactions and school-age children's narrative abilities in the context of financial insecurity

This longitudinal study investigates whether the quality of family interactions at 3-5 years of age predicts narrative abilities in 7-9-year-old children from socioeconomically disadvantaged families. The sample consists of 67 children and their parents receiving social welfare. Family interactions were filmed during mealtime at home and coded using the Mealtime Interaction Coding System. Children's narrative abilities were measured based on their capacity to coherently elaborate and resolve stories from the Attachment Story Completion Task. Results revealed that children exposed to family interactions of higher quality make their narratives more accessible and understandable and include more appropriate expression of affects in their stories 4 years later, even after accounting for maternal education and verbal abilities. The results of this study highlight the importance of considering family interactions in the context of financial insecurity when studying socioemotional competence in childhood.

Marital satisfaction, parenting stress, and family alliance: Parental perspective taking as a moderator

Research has shown that family alliance (FA), operationalized as the quality of mother-father-child triadic interactions, is important for child socioemotional development. However, few studies have investigated the predictors of FA, and there are few longitudinal studies available. Accordingly, this study first examined whether mothers' and fathers' marital satisfaction and parenting stress during infancy predicted FA five years later, when their children entered kindergarten. Second, the moderating role of both parents' perspective-taking capacity as a moderator of these longitudinal associations was examined. The study was conducted with 113 intact families (mother-father-child). Marital satisfaction, parenting stress, and perspective taking were reported by both parents and FA was assessed by observation. Contrary to expectations, neither parent's marital satisfaction or parenting stress was directly related to family alliance. However, significant moderating effects were found for both parents' perspective taking, such that higher paternal and maternal parenting stress predicted poorer FA only among parents with relatively lower perspective-taking capacities. These findings suggest that some aspects of the quality of family interactions when children enter school can be predicted by mothers' and fathers' personal dispositions assessed as early as five years prior.

Prospective associations between maternal mind-mindedness, child theory of mind, and brain morphology in school-aged children

Mentalizing is defined as the ability to attribute mental states to oneself and others. In the context of parental behavior, parents' tendency to comment on their child's mental activities refers to the concept of mind-mindedness (MM). MM has been positively associated with various developmental outcomes in children, notably their own ability to mentalize, known as theory of mind (ToM). Although parental (MM) and child (ToM) mentalizing have important implications during childhood, their associations with children's neural structures are largely unknown. Among 62 mother-child dyads, maternal MM was rated from free-play sequences when children were aged 1 year, child ToM was assessed using a first-order false-belief task at 4 years of age, and structural MRI images were acquired at 10 years of age. Maternal MM was positively associated with gray matter volumes (GMV) in the dorsal prefrontal cortex and the superior temporal pole. Child ToM abilities were positively associated with GMV in the ventromedial prefrontal cortex. Though cortical regions associated with MM and ToM showed no anatomical overlap, many are functionally connected through a neural network highly involved in self-referential strategies for mentalizing. These findings suggest that MM and ToM may contribute to distinct sub-processes that collectively support social cognition development.

Prenatal maternal stress during the COVID-19 pandemic and birth outcomes: Is the newborn spared?

The COVID-19 pandemic has generated numerous stressors among the general population, but more specifically in pregnant women because of disruptions in prenatal care and delivery conditions. Studies suggest that prenatal maternal stress increased during the pandemic (Berthelot et al., 2020; Perzow et al., 2021; Tomfohr-Madsen et al., 2021). Considering what is known about the fetal programming potential of prenatal maternal stress, several researchers, early in the pandemic, raised concerns over the significant negative consequences that the pandemic context could have on birth outcomes. Studies comparing birth outcomes during versus before the pandemic suggest a marginal increase in birthweight and a significant decrease in preterm birth (Yang et al., 2022), but individual variations in prenatal maternal stress during the pandemic have received less attention. The objective of the present study is to examine the association between prenatal maternal stress during the COVID-19 pandemic and birth outcomes. During pregnancy, 195 expecting mothers reported on their general and pandemic-related stress. When their child was 6 months old, mothers completed a questionnaire collecting information on birth outcomes (gestational age, birthweight, head circumference and Apgar scores). Hierarchical linear regressions show that none of the maternal prenatal stress variables significantly predicted variations in birth outcomes. Potential pandemic-related protective factors (e.g., changes in life and hygiene habits, rest imposed by lockdowns) and the need to offer support to pregnant women are discussed.

Habitual sleep and intraindividual variability of sleep in gifted children: an actigraphy study

STUDY OBJECTIVES

Giftedness is a multidimensional condition. It is increasingly put forward that gifted children (GC) could be a population at high risk for sleep problems. The current study investigated GC and typically developing children for their habitual sleep, night-to-night sleep variability, and parental reports of child sleep.

METHODS

The sample consisted of 62 GC (31 girls; mean age = 9.63 ± 1.71 years) and 62 typically developing children (31 girls; mean age = 9.68 ± 1.68 years). Groups were age and sex matched. Giftedness was identified using Renzulli's 3-factor definition of giftedness. Sleep duration, quality, and night-to-night variability were assessed using actigraphy. Parents were asked to complete the short-form version of the Children's Sleep Habits Questionnaire to report on their child's sleep. Groups were compared with independent sample t-tests and chi-square analyses.

RESULTS

GC displayed lower sleep efficiencies, more wake time after sleep onset, and more night-to-night sleep variability than typically developing children. GC were found to experience less social jetlag compared to typically developing children, and they also showed more clinically significant sleep problems as reported by parents.

CONCLUSIONS

Sleep maintenance and stability tend to be challenged in GC. While there is growing evidence that greater sleep variability is associated with poorer physical and emotional health, studies have yet to examine these associations in GC specifically to get a better understanding of giftedness. Overall, there is a need for research focused on both predictors and consequences of sleep patterns and sleep variability in GC.

CITATION

Bastien L, Théoret R, Bernier A, Godbout R. Habitual sleep and intraindividual variability of sleep in gifted children: an actigraphy study. J Clin Sleep Med. 2023;19(5):925-934.

Paternal mind-mindedness and children's academic achievement: Investigating developmental processes

This study tested a 5-year sequential mediation model linking paternal mind-mindedness in toddlerhood to child early academic achievement through a developmental process unfolding in the preschool years. A sample of 128 mostly White middle-class families (68 girls) living in Montreal, Canada was assessed for paternal mind-mindedness when children were 18 months old, child language at age 2, theory of mind and effortful control at age 4, cognitive school readiness in kindergarten, and finally, achievement in math and reading in first grade. Controlling for maternal mind-mindedness assessed at age 12 months, the results showed prospective associations from paternal mind-mindedness to both math and reading achievement, mediated by theory of mind, effortful control, and school readiness in sequence. Results suggest that paternal mind-mindedness may support child academic outcomes by promoting the acquisition of intermediate skills during preschool years. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Longitudinal associations between mother-child attachment security in toddlerhood and white matter microstructure in late childhood: a preliminary investigation

Early childhood experiences are considered to influence the strength and effectiveness of neural connections and thus the development of brain connectivity. As one of the most pervasive and potent early relational experiences, parent-child attachment is a prime candidate to account for experience-driven differences in brain development. Yet, knowledge of the effects of parent-child attachment on brain structure in typically developing children is scarce and largely limited to grey matter, whereas caregiving influences on white matter (i.e. neural connections) have seldom been explored. This study examined whether normative variation in mother-child attachment security predicts white matter microstructure in late childhood and explored associations with cognitive-inhibition. Mother-child attachment security was assessed using home observations when children (N = 32, 20 girls) were 15 and 26 months old. White matter microstructure was assessed using diffusion magnetic resonance imaging when children were 10 years old. Child cognitive-inhibition was tested when children were 11 years old. Results revealed a negative association between mother-toddler attachment security and child white matter microstructure organization, which in turn related to better child cognitive-inhibition. While preliminary given the sample size, these findings add to the growing literature that suggests that rich and positive experiences are likely to decelerate brain development.

Discrepancies between mother and father ratings of child behavior after early mild traumatic brain injury

Mild traumatic brain injuries (mTBI) are highly prevalent during early childhood and can lead to behavioral difficulties. Parent report questionnaires are widely used to assess children's behavior, but they are subject to parental bias. The aim of this study was to investigate parental discrepancies in internalized and externalized behavior ratings of children who sustain mTBI in early childhood (i.e., between 18 and 60 months) and to determine if parenting stress or family burden related to the injury contribute to parental discrepancies. Mothers and fathers of 85 children with mTBI, 58 orthopedic injured (OI), and 82 typically developing children (TDC) completed the Child Behavior Checklist 6 months after the injury. The primary caregiver completed the Parental Distress subscale of the Parenting Stress Index and the Family Burden of Injury Interview. Mothers reported more internalized and externalized behavior problems than fathers in the mTBI group. No group difference was found in the OI or TDC groups. Neither parenting stress nor family burden related to the injury predicted discrepancies in behavior ratings. Mothers' and fathers' perceptions of behavior after their young child sustains mTBI appear to differ, suggesting that both parents' views are useful in understanding outcome. This difference was not found in either of the comparison groups indicating that factors related to mTBI may underlie the rating discrepancies.

Conceptual comparison of constructs as first step in data harmonization: Parental sensitivity, child temperament, and social support as illustrations

This article presents a strategy for the initial step of data harmonization in Individual Participant Data syntheses, i.e., making decisions as to which measures operationalize the constructs of interest - and which do not. This step is vital in the process of data harmonization, because a study can only be as good as its measures. If the construct validity of the measures is in question, study results are questionable as well. Our proposed strategy for data harmonization consists of three steps. First, a unitary construct is defined based on the existing literature, preferably on the theoretical framework surrounding the construct. Second, the various instruments used to measure the construct are evaluated as operationalizations of this construct, and retained or excluded based on this evaluation. Third, the scores of the included measures are recoded on the same metric. We illustrate the use of this method with three example constructs focal to the Collaboration on Attachment Transmission Synthesis (CATS) study: parental sensitivity, child temperament, and social support. This process description may aid researchers in their data pooling studies, filling a gap in the literature on the first step of data harmonization.•Data harmonization in studies using combined datasets is of vital importance for the validity of the study results.•We have developed and illustrated a strategy on how to define a unitary construct and evaluate whether instruments are operationalizations of this construct as the initial step in the harmonization process.•This strategy is a transferable and reproducible method to apply to the data harmonization process.

Disorganized attachment behaviors in infancy as predictors of brain morphology and peer rejection in late childhood

Studies show robust links between disorganized attachment in infancy and socioemotional maladjustment in childhood. Little is known, however, about the links between disorganized attachment and brain development, and whether attachment-related differences in brain morphology translate into meaningful variations in child socioemotional functioning. This study examined the links between infants' disorganized attachment behaviors toward their mothers, whole-brain regional grey matter volume and thickness, and peer rejection in late childhood. Thirty-three children and their mothers took part in this study. The Strange Situation Procedure was used to assess mother-infant attachment when infants were 18 months old. Magnetic resonance imaging was performed when they were 10 years old to assess cortical thickness and grey matter volumes. Children and teachers reported on peer rejection 1 year later, as an indicator of socioemotional maladjustment. Results indicated that disorganized attachment was not associated with grey matter volumes. However, children who exhibited more disorganized attachment behaviors in infancy had significantly thicker cortices in bilateral middle and superior frontal gyri, and extending to the inferior frontal gyrus, as well as the orbitofrontal and insular cortices in the right hemisphere in late childhood. Moreover, children with thicker cortices in these regions experienced greater peer rejection, as rated by themselves and their teachers. Although preliminary, these results are the first to indicate that disorganized attachment may play a role in cortical thickness development and that changes in cortical thickness are associated with differences in child socioemotional functioning.

The role of multiple attachments in intergenerational transmission of child sexual abuse among male victims

BACKGROUND

According to Finkelhor (1984), difficulties child sexual abusers have in establishing adaptive adult relationships are a consequence of attachment problems with parents. Research shows that insecure attachment is associated with both the experience of child sexual abuse (CSA) as a victim and perpetration of CSA as an adult. Attachment may thus be a key factor in intergenerational transmission (IT) of CSA.

OBJECTIVE

The study aims to examine the direct, interactive, and mediated effects linking attachment in different relationships (mother, father, romantic partner) to IT of CSA among male victims.

PARTICIPANTS AND SETTING

Thirty-two abusing and 27 non-abusing male CSA survivors were recruited, respectively, in a prison and via networks of former foster children or CSA victims.

METHOD

All participants completed the Attachment Multiple Model Interview to assess attachment along four dimensions (security, deactivation, hyperactivation, and disorganization) in the relationship with mother, father, and partner.

RESULTS

Partial least square modeling suggests that the partner carries forward (mediates) the increased risk of committing sexual abuse associated with insecure/disorganized attachment with the father. A significant partner-mother interaction also suggests that the deleterious effects of attachment to the mother in terms of committing CSA are countered by more secure/organized attachment to the partner.

CONCLUSIONS

Findings highlight the pivotal role of the romantic partner in IT of CSA. Beyond early intervention, therapy in adulthood aimed at fostering adaptive ways of finding emotional security in the relationship with an adult could thus be encouraged.

Transmission of parental childhood trauma to child behavior problems: Parental Hostile/Helpless state of mind as a moderator

BACKGROUND

Little attention has been given to intergenerational transmission of risk, mainly whether caregivers' history of childhood maltreatment is linked to behavioral symptoms in their children and which protective/risk factors are involved in this transmission process.

OBJECTIVE

This study examined if parental Hostile/Helpless (H/H) state of mind with respect to attachment moderated the association between parental childhood trauma and behavior problems in maltreated children.

PARTICIPANTS AND SETTING

The sample included 61 parents and their children victims or at very high risk of maltreatment, aged between 1 and 6 years old.

METHOD

Parents retrospectively reported their childhood trauma and completed a measure of their children's behavior problems. Independent observers assessed H/H attachment representations.

RESULTS

Among parents with H/H states of mind, more severe traumatic childhood experiences were associated with more externalizing and internalizing behavior problems in their children. Among non-H/H parents, associations between parental childhood trauma and child behavior problems were not significant.

CONCLUSIONS

In the context of trauma, this study suggests that the absence of a H/H state of mind in parents (i.e., the presence of an organized attachment state of mind) is a protective factor for child adjustment. H/H mental representations of self and attachment experiences as targets of intervention for parents with histories of maltreatment may help reduce the transmission of risk in maltreating families.

Mother-child interactions and child anger proneness as antecedents of changes in sleep during the preschool period

Age-related developments in sleep during the preschool years are normative and consequential. Yet, very few studies have examined the antecedents of individual differences in such developments, and most have used parental reports of child sleep. This study aimed to investigate the roles of mutual responsiveness in mother-child interactions and child temperamental anger proneness in the prediction of changes in sleep during the preschool period. The sample was comprised of 94 children (44 girls, 50 boys) of mostly White (93%) and college-educated (85%) mothers. Mother-child mutual responsiveness and child anger proneness were assessed at 2 years, and sleep was assessed using actigraphy at the ages of 2, 3, and 4 years. Multilevel growth models revealed that higher temperamental anger proneness was concurrently associated with lower sleep efficiency and shorter nighttime sleep duration at 2 years. In regard to changes in sleep, nighttime sleep duration decreased between 2 and 4 years among children exposed to lower mutual responsiveness in interactions with their mothers. High anger proneness was related to an increase in sleep efficiency from 2 to 4 years, whereas low anger proneness was associated with a decrease in nighttime duration during the same period. No interactive effect was found between anger proneness and mother-child mutual responsiveness. These results suggest that mother-child relationships and child temperament may play different roles, not only in children's concurrent sleep patterns but also in changes in sleep across the preschool period. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Family alliance as a developmental antecedent of depressive and anxiety symptoms in early adolescence: Friendship quality as a mediating factor

Family interactions constitute a critical context in which children can learn the basic relational skills that they need to make friends. In turn, friendship quality is a robust predictor of child socioemotional functioning. Therefore, friendship is likely to act as a bridge in a socioemotional developmental cascade linking early family interactions to child subsequent socioemotional adjustment. This study aimed to examine a mediation model linking family alliance (the degree of mother-father-child engagement and coordination in joint activities) in kindergarten to anxiety and depressive symptoms in early adolescence through the mediating role of friendship quality in middle childhood. The family alliance of 87 mother-father-child triads was assessed when children were aged 6 years based on a 15-min videotaped interaction. Children reported on the quality of their relationship with their best friend at age 10 and on their anxiety and depressive symptoms at both 12 and 13 years (averaged). Results showed that children who experienced better family alliance at 6 years had higher relationship quality with their best friend at 10 years which in turn, predicted less anxiety (but not depressive) symptoms in early adolescence. There was a significant indirect effect of family alliance on anxiety through friendship quality. Findings suggest that family alliance may play a central role in shaping children's capacity to develop high-quality friendships, with implications for their subsequent socioemotional functioning. Further longitudinal studies are needed to examine the reciprocal influences unfolding over time that are likely to characterize developmental cascades among family systems, children's developing friendships, and their socioemotional functioning.

Exploring the relationships between child maltreatment and risk factors for pregnancy complications

OBJECTIVE

This study explored the pathway underlying the relationships between child maltreatment (CM) subtypes (i.e., physical, sexual, and emotional abuse and neglect) and factors associated with a heightened risk of pregnancy complications by examining post-traumatic stress disorder (PTSD) symptoms as a potential mediator.

METHODS

A sample of 98 pregnant parents between the ages of 18 and 29 years was recruited through social media and community organizations throughout Canada. Participants completed a series of surveys on their exposure to CM, PTSD symptoms, and pregnancy experiences on a secure online platform. Following data cleaning procedures, 85 participants were included in this study.

RESULTS

Four separate mediation analyses were conducted with child neglect, physical abuse, sexual abuse, and emotional abuse as factors associated with a heightened risk of pregnancy complications (i.e., a congregate score of limited prenatal care, weight gain concerns, smoking, second-hand smoke, alcohol consumption, substance use, and insufficient food intake during pregnancy). Each CM subtype was associated with increased PTSD symptoms, which were in turn associated with the presence of more factors known for increasing the risk of pregnancy complications. Neglect, physical abuse, sexual abuse, and emotional abuse were all indirectly associated with the presence of more factors associated with a heightened risk of pregnancy complications through their association with PTSD symptoms.

CONCLUSIONS

Findings from this study could encourage prenatal care providers to screen for CM history and PTSD symptoms. Furthermore, mental health treatment early in the prenatal period may improve pregnant parents' health and lower their risk of pregnancy complications.

The Mechanism and Consequences of SARS-CoV-2 Spike-Mediated Fusion and Syncytia Formation

Syncytia are formed when individual cells fuse. SARS-CoV-2 induces syncytia when the viral spike (S) protein on the surface of an infected cell interacts with receptors on neighboring cells. Syncytia may potentially contribute to pathology by facilitating viral dissemination, cytopathicity, immune evasion, and inflammatory response. SARS-CoV-2 variants of concern possess several mutations within the S protein that enhance receptor interaction, fusogenicity and antibody binding. In this review, we discuss the molecular determinants of S mediated fusion and the antiviral innate immunity components that counteract syncytia formation. Several interferon-stimulated genes, including IFITMs and LY6E act as barriers to S protein-mediated fusion by altering the composition or biophysical properties of the target membrane. We also summarize the effect that the mutations associated with the variants of concern have on S protein fusogenicity. Altogether, this review contextualizes the current understanding of Spike fusogenicity and the role of syncytia during SARS-CoV-2 infection and pathology.

Quality of father-child relationships as a predictor of sleep developments during preschool years

Substantial developmental changes in sleep occur during the preschool period, but few studies have investigated the factors that forecast these developments. The aim of this study was to examine whether three aspects of father-child relationships in toddlerhood predicted individual differences in developmental patterns of change in five actigraphy-derived sleep variables during the preschool period (N = 67; sleep assessed yearly between 2 and 4 years). In a predominantly White and middle-to-higher income sample, paternal mind-mindedness and quality of father-child interactions were assessed during father-child free play at 18 months and fathers self-reported on their involvement in childrearing at age 2. Multilevel growth modeling revealed that children whose father made more mind-related comments during father-child interactions had a higher proportion of sleep taking place during nighttime as well as shorter daytime and total sleep duration at 2 years. This was, however, followed by a relative leveling off (i.e., less rapid change) of these sleep features between 2 and 4 years. Given previous studies documenting that nighttime sleep proportion increases while daytime and total sleep duration decrease during preschool years, the findings suggest that children who are exposed to more paternal mind-mindedness may reach more mature sleep patterns earlier in development.

Further evidence for the multidimensional nature of maternal sensitivity: differential links with child socioemotional functioning at preschool age

There has been increasing scholarly attention to the study of maternal sensitivity as a multidimensional construct. This report investigated the predictive value of three dimensions of sensitivity during mother-infant interactions in an effort to gain greater understanding of how specific facets of sensitivity relate to child socioemotional outcomes. Maternal cooperation/attunement (accurate interpretation of infant cues and capacity to adjust the interaction correspondingly), positivity (positive attitude toward the infant), and accessibility/availability (consistent attentiveness) were assessed observationally in 195 mothers of 1-year-old infants. Child socioemotional functioning was assessed using behavioral tasks and maternal and teacher reports when children were 4 years of age. The results revealed that maternal accessibility/availability was predictive of less externalizing behavior, more prosocial behavior (mother- and teacher-reported), and better theory of mind, while maternal positivity predicted effortful control. These results highlight the advantages of a multidimensional assessment in understanding how sensitivity predicts different developmental outcomes.

Sleep development in preschool predicts executive functioning in early elementary school

This report investigates the role of normative developments in sleep during preschool years in the prediction of child EF performance at early school age. Sleep was assessed by actigraphy at ages 2, 3, and 4, and EF with behavioral tasks when children were in Grade 2. The results revealed that children whose sleep followed expected developmental trends more rapidly showed better EF performance: a more pronounced decrease in sleep duration between ages 2 and 4 predicted better subsequent working memory, whereas a more pronounced increase in sleep efficiency was predictive of better inhibitory control performance. These findings suggest that age-related development may be a key characteristic of sleep as it relates to children's executive skills.

Kids' Outcomes And Long-term Abilities (KOALA): protocol for a prospective, longitudinal cohort study of mild traumatic brain injury in children 6 months to 6 years of age

INTRODUCTION

Mild traumatic brain injury (mTBI) is highly prevalent, especially in children under 6 years. However, little research focuses on the consequences of mTBI early in development. The objective of the Kids' Outcomes And Long-term Abilities (KOALA) study is to document the impact of early mTBI on children's motor, cognitive, social and behavioural functioning, as well as on quality of life, stress, sleep and brain integrity.

METHODS AND ANALYSES

KOALA is a prospective, multicentre, longitudinal cohort study of children aged 6 months to 6 years at the time of injury/recruitment. Children who sustain mTBI (n=150) or an orthopaedic injury (n=75) will be recruited from three paediatric emergency departments (PEDs), and compared with typically developing children (community controls, n=75). A comprehensive battery of prognostic and outcome measures will be collected in the PED, at 10 days, 1, 3 and 12 months postinjury. Biological measures, including measures of brain structure and function (magnetic resonance imaging, MRI), stress (hair cortisol), sleep (actigraphy) and genetics (saliva), will complement direct testing of function using developmental and neuropsychological measures and parent questionnaires. Group comparisons and predictive models will test the a priori hypotheses that, compared with children from the community or with orthopaedic injuries, children with mTBI will (1) display more postconcussive symptoms and exhibit poorer motor, cognitive, social and behavioural functioning; (2) show evidence of altered brain structure and function, poorer sleep and higher levels of stress hormones. A combination of child, injury, socioenvironmental and psychobiological factors are expected to predict behaviour and quality of life at 1, 3 and 12 months postinjury.

ETHICS AND DISSEMINATION

The KOALA study is approved by the Sainte-Justine University Hospital, McGill University Health Centre and University of Calgary Conjoint Health Research Ethics Boards. Parents of participants will provide written consent. Dissemination will occur through peer-reviewed journals and an integrated knowledge translation plan.

Prospective relations between sleep in preschool years and academic achievement at school entry

It is often assumed that adequate sleep is a key ingredient of children's school success. Research to date, however, suggests modest associations between child sleep and academic achievement. Adopting a developmental perspective, this report investigates the associations between age-related changes in sleep across the preschool period and academic achievement at school entry. Sleep was assessed by actigraphy at ages 2, 3 and 4 among 128 children from mostly White middle-class families, and their performance in reading and mathematics was tested in Grade 1. The results revealed that children whose sleep duration decreased more rapidly across the preschool period showed better performance in both reading and mathematics. These results suggest that age-related developments may be a key characteristic of sleep in the preschool years.

Brain-Derived Neurotrophic Factor Val66Met Polymorphism and Internalizing Behaviors after Early Mild Traumatic Brain Injury

Pediatric traumatic brain injury (TBI) can lead to adverse emotional, social, and behavioral consequences. However, outcome is difficult to predict due to significant individual variability, likely reflecting a complex interaction between injury- and child-related variables. Among these variables are genetically determined individual differences, which can modulate TBI outcome through their influence on neuroplasticity mechanisms. In this study, we examined the effect of Val66Met, a common polymorphism of the brain-derived neurotrophic factor gene known to be involved in neuroplasticity mechanisms, on behavioral symptoms of mild TBI (mTBI) sustained in early childhood. This work is part of a prospective, longitudinal cohort study of early TBI. The current sample consisted of 145 children between ages 18 and 60 months assigned to one of three participant groups: mild TBI, orthopedic injury, or typically developing children. Participants provided a saliva sample to detect the presence of the Val66Met polymorphism, and the Child Behavior Checklist was used to document the presence of behavioral symptoms at 6- and 18-months post-injury. Contrary to our initial hypothesis, at 6 months post-injury, non-carriers of the Val66Met polymorphism in the mTBI group presented significantly more internalizing symptoms (e.g., anxiety/depression and somatic complaints) than Val66Met carriers, who were similar to orthopedically injured and typically developing children. However, at 18 months post-injury, all children with mTBI presented more internalizing symptoms, independent of genotype. The results of the study provide evidence for a protective effect of the Val66Met polymorphism on internalizing behavior symptoms 6 months after early childhood mTBI.

Disentangling the Direction of Associations between Sleep and Temperament in Toddlers

OBJECTIVES/BACKGROUND

Although much research has investigated the associations between children's sleep and their temperament, the direction of these associations remains unclear, largely due to a lack of longitudinal studies with repeated assessments of both sleep and temperament. Aiming to clarify the temporal precedence of these two constructs, the current study investigated reciprocal associations between toddlers' sleep and temperament with a longitudinal design.

PARTICIPANTS

The sample consisted of 82 toddlers (39 girls) assessed twice.

METHODS

At both 2 (M = 25.23 months; SD = 1.11) and 3 years of age (M = 36.81 months; SD = 0.91), toddlers' sleep duration and quality were assessed using actigraphy and their temperament was reported by their mothers with the Toddler Behavior Assessment Questionnaire.

RESULTS

Shorter nighttime sleep duration (ß = - .28, p = .03) and lower sleep efficiency (ß = - .33, p = .01) at 2 years predicted more temperamental proneness to anger at 3 years, while greater temperamental social fear at 2 years was predictive of shorter 24-hour (ß = - .44, p = .02) and nighttime (ß = - .36, p = .04) sleep duration at 3 years. Associations between temperamental activity level and sleep variables were non-significant.

CONCLUSION

The direction of the associations between toddlers' sleep and their temperament may vary according to which dimension of temperament is considered. These findings should encourage practitioners to identify the beginning of the causal chain leading to sleep or temperamental difficulties so as to develop well-tailored intervention plans.

Socioeconomic Status in Infancy and the Developing Brain: Functional Connectivity of the Hippocampus and Amygdala

The development of the hippocampus and amygdala is particularly sensitive to environmental factors, including socioeconomic status (SES). Studies that have investigated associations between SES and brain development markers have rarely focused on connectivity. Accordingly, this longitudinal study examined whether SES in infancy (parental education and income-to-needs ratio) predicts the functional connectivity of the hippocampus and amygdala in late childhood, and in turn whether functional connectivity is associated with child socioemotional adjustment in a middle-class sample. SES indices were measured when children (n = 28) were 7 months old. When children were 10 years of age, they underwent a resting-state functional magnetic resonance imaging exam, and their school teachers completed a questionnaire assessing child socioemotional adjustment. Whole-brain regression analyses, including left and right hippocampi and amygdalae as seeds and SES indices as predictors, revealed that higher parental education predicted stronger functional connectivity between the left and right hippocampi and the right amygdala with the dorsal anterior cingulate cortex, and between the left amygdala and bilateral angular gyrus, after accounting for child age and sex. In turn, the connectivity of these regions was associated with higher child prosocial behavior. These findings contribute to the emerging literature suggesting that SES is associated with variability in the neural substrates of social abilities in children.

Persistent Changes in Child Behavior After Early Mild Traumatic Brain Injury

OBJECTIVE

To document longitudinal changes in internalizing and externalizing behavioral symptoms after mild traumatic brain injury (mTBI) sustained in early childhood (i.e., between 18 and 60 months of age).

METHODS

Participants (N = 226) were recruited to one of three groups: children with mTBI, typically developing children and orthopedic injured children. The Child Behavior Checklist was used to document the presence of internalizing and externalizing behaviors at 6, 18, and 30 months postinjury. Linear mixed-model analyses were used to examine group effects on the trajectory of internalizing and externalizing behavioral manifestations over 30 months postinjury.

RESULTS

Children who sustain mTBI during the preschool period have higher rates of internalizing and externalizing behavioral symptoms at the initial assessment time point and these symptoms persist up to 30 months postinjury. Moreover, results indicate that for up to 18 months postinjury, significantly more children with mTBI present behavioral difficulties that may require some form of clinical attention (i.e., scores in the borderline or clinical range), than do their orthopedically injured and noninjured peers.

CONCLUSIONS

Sustaining mTBI early in life may lead to long-lasting behavioral changes in young children (i.e., at least 30 months). These changes are likely the product of a complex interplay between neurological and non-neurological factors, both contributing to generating and maintaining behavioral difficulties.

miR-122 does not impact recognition of the HCV genome by innate sensors of RNA but rather protects the 5' end from the cellular pyrophosphatases, DOM3Z and DUSP11

Hepatitis C virus (HCV) recruits two molecules of the liver-specific microRNA-122 (miR-122) to the 5′ end of its genome. This interaction promotes viral RNA accumulation, but the precise mechanism(s) remain incompletely understood. Previous studies suggest that miR-122 is able to protect the HCV genome from 5′ exonucleases (Xrn1/2), but this protection is not sufficient to account for the effect of miR-122 on HCV RNA accumulation. Thus, we investigated whether miR-122 was also able to protect the viral genome from innate sensors of RNA or cellular pyrophosphatases. We found that miR-122 does not play a protective role against recognition by PKR, RIG-I-like receptors, or IFITs 1 and 5. However, we found that knockdown of both the cellular pyrophosphatases, DOM3Z and DUSP11, was able to rescue viral RNA accumulation of subgenomic replicons in the absence of miR-122. Nevertheless, pyrophosphatase knockdown increased but did not restore viral RNA accumulation of full-length HCV RNA in miR-122 knockout cells, suggesting that miR-122 likely plays an additional role(s) in the HCV life cycle, beyond 5′ end protection. Overall, our results support a model in which miR-122 stabilizes the HCV genome by shielding its 5′ terminus from cellular pyrophosphatase activity and subsequent turnover by exonucleases (Xrn1/2).

Factors contributing to parent-child interaction quality following mild traumatic brain injury in early childhood

There is emerging evidence that parent-child interactions are affected by early childhood traumatic brain injury (TBI). These findings are of functional importance when considering the high prevalence of TBI in early childhood alongside evidence that young children exposed to positive relationships with their parents early in life exhibit better social functioning concurrently and longitudinally. Given that the overall quality of parent-child interactions is the result of both parent and child emotional and behavioural dispositions, it remains unclear which parental or child-related factors contribute to the quality of interactions post-TBI. The aim of this study was to investigate the factors that contribute to the quality of parent-child interactions following early childhood TBI. The sample included 68 children (18-60 months at recruitment) with accidental, uncomplicated mild TBI (mTBI). The quality of parent-child interactions was assessed 6 months post-injury using the Mutually Responsive Orientation scale, an observational measure of the dyadic quality of parent-child exchanges. Potential contributing factors were assessed among parental factors (e.g., age, socioeconomic status, family burden, parental stress, marital satisfaction) and child-related factors (e.g., age, sex, symptoms, fatigue, adaptive/behavioural skills). Socioeconomic status, child post-concussive symptoms, and child sleep problems were found to be significant independent contributing factors to parent-child interactions six months post-injury. This study provides the first evidence that both parental and child factors relate to the quality of parent-child interactions following mTBI, thus contributing to a better understanding of the scope and complexity of factors that play a role in childrens' recovery.

Beyond sites 1 and 2, miR-122 target sites in the HCV genome have negligible contributions to HCV RNA accumulation in cell culture

Hepatitis C virus (HCV) recruits two molecules of the liver-specific microRNA-122 (miR-122) to two adjacent sites (S1 and S2) located at the 5' end of the viral RNA genome. This interaction promotes HCV RNA accumulation by stabilising the viral RNA and resulting in alteration of the secondary structure of the viral genome. In addition to S1 and S2, the HCV genome contains several other putative miR-122 binding sites, one in the IRES region, three in the NS5B coding region, and one in the 3' UTR. We investigated and compared the relative contributions of the S1, S2, IRES, NS5B (NS5B.1, 2 and 3) and 3' UTR sites on protein expression, viral RNA accumulation, and infectious particle production by mutational analysis and supplementation with compensatory mutant miR-122 molecules. We found that mutations predicted to alter miR-122 binding at the IRES and NS5B.2 sites lead to reductions in HCV core protein expression and viral RNA accumulation; with a concomitant decrease in viral particle production for the NS5B.2 mutant. However, supplementation of miR-122 molecules with compensatory mutations did not rescue these site mutants to wild-type levels, suggesting that mutation of these sequences likely disrupts an additional interaction important to the HCV life cycle, beyond direct interactions with miR-122. Thus, S1 and S2 play a predominant role in viral RNA accumulation, while miR-122 interactions with the IRES, NS5B and 3' UTR regions have negligible contributions to viral protein expression, viral RNA accumulation, and infectious particle production.

Borderline Personality Disorder in Adolescence as a Generalization of Disorganized Attachment

Several researchers point to disorganized attachment as a core feature of borderline personality disorder (BPD). However, recent studies suggest that specific internal working models (IWMs) of each parent combine to account for child outcomes and that a secure relationship with one parent can protect against the deleterious effects of an insecure relationship with the other parent. It was thus hypothesized that adolescents with BPD are more likely to be disorganized with both their parents, whereas non-clinical controls are more secure with at least one of their caregivers. Thirty-six adolescents with BPD and 30 control participants (aged 13-19) were included. Psychiatrist diagnosis was verified with the Structured Interview for DSM-IV Personality Disorders (SIDP-IV) and comorbidity was assessed using the Kiddie-SADS. Reported trauma was assessed with the Childhood Trauma Questionnaire (CTQ). Attachment IWMs of each parent were assessed with the Attachment Multiple Model Interview (AMMI), which enables separate coding for each attachment figure and in which disorganization is conceptualized as conflicting attachment strategies within a specific relationship. Results of a logistic regression analysis suggested that beyond insecure attachment, being disorganized not just with one but with both parents is particularly characteristic of adolescents with BPD. Conversely, belonging to the non-clinical group was predicted by higher security scores with the father and lower deactivation with the mother. Although higher levels of childhood abuse or neglect were reported by adolescents with BPD, the retained attachment dimensions predicted group membership over and above reported trauma. These findings have important implications for clinical intervention and highlight the protective role fathers may have.

From Early Relationships to Preacademic Knowledge: A Sociocognitive Developmental Cascade to School Readiness

This study aimed to test a four-wave sequential mediation model linking mother-child attachment to children's school readiness through child executive functioning (EF) and prosociality in toddlerhood and the preschool years. Mother-child attachment security was assessed when children (N = 255) were aged 15 months and 2 years, child EF at age 2, prosocial behavior at age 4, and finally cognitive school readiness in kindergarten (age 6). The results revealed three indirect pathways linking attachment to school readiness: one through EF only, one through prosocial behavior only, and a last pathway involving both EF and prosocial behavior serially. These findings suggest that secure attachment may equip children with both cognitive and social skills that are instrumental to their preparedness for school.