Neonatal Nucleus Accumbens Microstructure Modulates Individual Susceptibility to Preconception Maternal Stress in Relation to Externalizing Behaviors.

OBJECTIVE: Maternal stress influences in utero brain development and is a modifiable risk factor for offspring psychopathologies. Reward circuitry dysfunction underlies various internalizing and externalizing psychopathologies. This study examined (1) the association between maternal stress and microstructural characteristics of the neonatal nucleus accumbens (NAcc), a major node of the reward circuitry, and (2) whether neonatal NAcc microstructure modulates individual susceptibility to maternal stress in relation to childhood behavioral problems. METHOD: K-means longitudinal cluster analysis was performed to determine trajectories of maternal stress measures (Perceived Stress Scale [PSS], hair cortisol) from preconception to the third trimester. Neonatal NAcc microstructural measures (orientation density index [ODI] and intracellular volume fraction [ICVF]) were compared across trajectories. We then examined the interaction between maternal stress and neonatal NAcc microstructure on child internalizing and externalizing behaviors, assessed between ages 3 and 4 years. RESULTS: Two trajectories of maternal stress magnitude ("low"/"high") were identified for both PSS (n = 287) and hair cortisol (n = 336). Right neonatal NAcc ODI (rNAcc-ODI) was significantly lower in "low" relative to "high" PSS trajectories (n = 77, p = .04). PSS at preconception had the strongest association with rNAcc-ODI (r = 0.293, p = .029). No differences in NAcc microstructure were found between hair cortisol trajectories. A significant interaction between preconception PSS and rNAcc-ODI on externalizing behavior was observed (n = 47, p = .047). CONCLUSION: Our study showed that the preconception period contributes to in utero NAcc development, and that NAcc microstructure modulates individual susceptibility to preconception maternal stress in relation to externalizing problems.

Physical discipline as a normative childhood experience in Singapore.

BACKGROUND: The cultural normativeness theory posits that specific parenting behaviors can be interpreted as displays of appropriate parenting in contexts where they are deemed normative. Previous studies suggest high acceptance of physical discipline in Singapore, where strict parenting could be interpreted as care for the child. However, there is a lack of studies on the local prevalence and implications of physical discipline. This study aimed to investigate the prevalence of Singaporean children experiencing parental physical discipline, longitudinal changes in this prevalence, and how exposure to physical discipline relates to children's evaluation of their parents' parenting. METHODS: Participants were 710 children with parental reports of physical discipline at one or more assessments at ages 4.5, 6, 9, and 11 years in the Growing Up in Singapore Towards healthy Outcomes birth cohort study. Parental reports of physical discipline were obtained using the Parenting Styles and Dimensions Questionnaire or the Alabama Parenting Questionnaire across the four assessments. Child reports of their parents' care and control were obtained using the Parental Bonding Instrument for Children at the age 9 assessment. Prevalence was specified as being exposed to at least one physical discipline at any frequency. A generalized linear mixed model was performed to examine whether children's age predicted their exposure to physical discipline. Linear regression analyses were conducted to investigate whether children's exposure to physical discipline predicted their evaluation of their parents' parenting. RESULTS: The prevalence of children experiencing at least one physical discipline was above 80% at all ages. There was a decrease in this prevalence from age 4.5 to 11 years (B = - 0.14, SE = 0.01, OR = 0.87, p < 0.001). The more frequent the paternal physical discipline children were exposed to, the more likely they were to report lower levels of care (B = - 1.74, SE = 0.66, p = 0.03) and higher levels of denial of psychological autonomy by fathers (B = 1.05, SE = 0.45, p = 0.04). Maternal physical discipline was not significantly associated with children's evaluation of their mothers' parenting (ps ≥ 0.53). CONCLUSIONS: Physical discipline was a common experience among our Singaporean sample, consistent with the notion that strict parenting could be regarded as a form of care. However, exposure to physical discipline did not translate to children reporting their parents as caring, with paternal physical discipline being negatively associated with children's evaluations of paternal care.

Maternal distress and parenting during COVID-19: differential effects related to pre-pandemic distress?

BACKGROUND: Distinguishing whether and how pre-existing characteristics impact maternal responses to adversity is difficult: Does prior well-being decrease the likelihood of encountering stressful experiences? Does it protect against adversity's negative effects? We examine whether the interaction between relatively uniformly experienced adversity (due to COVID-19 experience) and individual variation in pre-existing (i.e., pre-pandemic onset) distress predicted mothers' pandemic levels of distress and insensitive caregiving within a country reporting low COVID-19 death rates, and strict nationwide regulations. METHOD: Fifty-one Singaporean mothers and their preschool-aged children provided data across two waves. Pre- pandemic onset maternal distress (i.e., psychological distress, anxiety, and parenting stress) was captured via self-reports and maternal sensitivity was coded from videos. Measures were repeated after the pandemic's onset along with questionnaires concerning perceived COVID-19 adversity (e.g., COVID-19's impact upon stress caring for children, housework, job demands, etc.) and pandemic-related objective experiences (e.g., income, COVID-19 diagnoses, etc.). Regression analyses (SPSS v28) considered pre-pandemic onset maternal distress, COVID-19 stress, and their interaction upon post-pandemic onset maternal distress. Models were re-run with appropriate covariates (e.g., objective experience) when significant findings were observed. To rule out alternative models, follow up analyses (PROCESS Model) considered whether COVID-19 stress mediated pre- and post-pandemic onset associations. Models involving maternal sensitivity followed a similar data analytic plan. RESULTS: Pre-pandemic maternal distress moderated the association between COVID-19 perceived stress and pandemic levels of maternal distress (ß = 0.22, p < 0.01) but not pandemic assessed maternal sensitivity. Perceived COVID-19 stress significantly contributed to post-pandemic onset maternal distress for mothers with pre-pandemic onset distress scores above (ß = 0.30, p = 0.05), but not below (ß = 0.25, p = 0.24), the median. Objective COVID-19 adversity did not account for findings. Post-hoc analyses did not suggest mediation via COVID-19 stress from pre-pandemic to pandemic maternal distress. CONCLUSIONS: Pre-existing risk may interact with subsequent perceptions of adversity to impact well-being. In combination with existing research, this small study suggests prevention programs should focus upon managing concurrent mental health and may highlight the importance of enhanced screening and proactive coping programs for people entering high stress fields and/or phases of life.

Chronotype and time-of-day effects on spatial working memory in preschool children.

STUDY OBJECTIVES: Spatial working memory (SWM) capacity subserves complex cognitive functions, yet it is unclear whether individual diurnal preferences and time-of-day influence SWM in preschool children. The main and interaction effects of chronotype and time-of-day on SWM and SWM differences in preschoolers with different chronotypes within each time-of-day group will be examined. METHODS: We studied a subset of typically developing 4.5-year-olds taking part in a birth cohort study (n = 359). The Children's Chronotype Questionnaire categorized children into morning-, intermediate-, and evening-types. Using a computerized neuropsychological test (Cambridge Neuropsychological Test Automated Battery), SWM was determined from the total number of between-search errors (ie, between search-total errors) and Strategy scores. Higher between search-total errors or lower Strategy scores indicated worse SWM. Time-of-day was categorized into late morning (10:00 am to 11:59 am), afternoon (12:00 pm to 3:59 pm), and late afternoon (4:00 pm to 6:30 pm). In a subsample (n = 199), caregiver-reported chronotype was validated using actigraphy-measured sleep midpoint. RESULTS: After controlling for ethnicity, no significant main and interaction effects of chronotype and time-of-day on between search-total errors and Strategy scores were seen (all P > .05). However, evening-types outperformed morning-types (ie, lower mean between search-total errors) in the late afternoon (P = .013) but not in the late morning and afternoon (all P > .05). Actigraphy data in the subsample confirmed that evening-types had later sleep midpoints during weekdays and weekends (P < .001). CONCLUSIONS: Since evening-type preschoolers had better SWM in the late afternoon compared to morning-type preschoolers, this gives insights into optimal learning opportunities in early childhood education. CITATION: Abdul Jafar NK, Tham EKH, Eng DZH, et al. Chronotype and time-of-day effects on spatial working memory in preschool children. J Clin Sleep Med. 2023;19(10):1717-1726.

Preconception sleep quality moderates the association between preconception hair cortisol levels and mental health in pregnant women.

BACKGROUND: Poor sleep quality may elevate cortisol levels and affect prenatal mental health through altered HPA axis functioning. This study aims to examine whether subjective sleep quality during preconception moderates the association between preconception hair cortisol levels and mental health from preconception to pregnancy trimesters. METHODS: Women from a prospective cohort study completed the Pittsburgh Sleep Quality Index (PSQI), the Edinburgh Postnatal Depression Scale (EPDS), and the State-Trait Anxiety Inventory (STAI) questionnaires during preconception (T0) and at each pregnancy trimesters (T1, T2, and T3). We analyzed 266 of these women who conceived and had fully completed measures at preconception for hair cortisol, sleep quality and either EPDS or STAI-state. Changes in EPDS and STAI-state scores were derived (i.e., T1-T0, T2-T0, T3-T0). Johnson-Neyman technique identified PSQI scores with significant moderation of cortisol on mental health. RESULTS: After adjusting for potential covariates, there was a significant positive correlation between preconception hair cortisol levels and depressive symptom at the second trimester (rs (144) = 0.22, p = 0.008), but not the first and third trimesters (all ps > 0.05). The positive association between preconception hair cortisol and change in depressive symptoms between third trimester and preconception was significant only among women with poor preconception sleep quality (PSQI ≥ 7). LIMITATIONS: Sleep quality and prenatal mood were derived from self-reported questionnaires, which may be more susceptible to bias. CONCLUSIONS: The positive association between preconception hair cortisol and change in prenatal depressive symptoms is significant among women who reported poor sleep quality during preconception. Improving preconception sleep quality can potentially mitigate the association between preconception hair cortisol and depressive symptoms during pregnancy.

Nutrient trajectories during infancy and their associations with childhood neurodevelopment.

PURPOSE: To examine the associations between infants' dietary nutrient trajectories and subsequent neurodevelopment during childhood in the Growing Up in Singapore Towards healthy Outcomes study. METHODS: One-day food records were collected at ages 6, 9 and 12 months, whilst Bayley Scales of Infant and Toddler Development-III and Kaufman Brief Intelligence Test-2 were conducted at ages 24 and 54 months respectively. Nutrient trajectories were constructed using multi-level mixed modelling and associations with neurodevelopment (24 months: n = 484; 54 months: n = 444) were examined using adjusted multivariable linear regression. RESULTS: At age 24 months, higher protein intake (at 6 months) and increasing rate of intake (from 6 to 12 months) were associated with higher fine motor score [ß = 0.17 SD (95% CI 0.03, 0.31) and 0.62 SD (0.10, 1.14) respectively]. Higher fat intake was associated with higher receptive language score [0.04 SD (0.003, 0.07)], but increasing rate of intake was associated with lower expressive language [- 0.20 SD (- 0.39, - 0.01)] and fine motor [- 0.29 SD (- 0.48, - 0.10)] scores. Higher carbohydrate intake was associated with lower gross motor score [- 0.07 SD (- 0.14, - 0.005)], but increasing rate of intake was associated with higher receptive language [0.44 SD (0.08, 0.81)] and fine motor [0.56 SD (0.18, 0.93)] scores. Increasing rate of dietary fibre intake was associated with higher fine motor scores [0.63 SD (0.16, 1.10)]. No significant associations were observed with neurodevelopment at 54 months. CONCLUSION: Our findings provide greater understanding of how nutrition over time could have varying effects on child neurodevelopment.

Variation in maternal sensitivity and the development of memory biases in preschoolers.

Introduction: Links between maternal sensitivity, hippocampal development, and memory abilities suggests early life insensitive care may shape structures and schemas influencing future decisions and stress management, biasing children to negative information. While it is possible that this pattern of neurodevelopment may have adaptive consequences, for example, preventing children from encountering untoward experience with future adversity, it may also leave some children at risk for the development of internalizing problems. Methods: Here, in a Two Wave Study, we examine whether insensitive care predicts sub sequentially assessed memory biases for threatening (but not happy) stimuli in preschoolers (n = 49), and if such relations cut across different forms of relational memory, i.e., memory for relations between two "items," between an "item" and its spatial location, and an "item" and its temporal sequence. In a subset (n = 18) we also examine links between caregiving, memory, and hippocampal subregion volume. Results: Results indicate no main or interactive influence of gender on relational memory. However, insensitive caregiving predicted the difference between Angry and Happy memory during the Item-Space condition (B = 2.451, se = 0.969, p = 0.014, 95% CI (0.572, 4.340)], as well as memory for Angry (but not Happy) items [B = -2.203, se = 0.551, p < 0.001, 95% CI (-3.264,-1.094)]. Memory for the difference between Angry and Happy stimuli in the Space condition associated with larger right hippocampal body volumes (Rho = 0.639, p = 0.004). No relations were observed with internalizing problems. Discussion: Results are discussed with reference to developmental stage and in consideration of whether negative biases may serve as an intermediate factor linking early life insensitive care and later socioemotional problems including an increased incidence of internalizing disorders.

Associations Between Infant Screen Use, Electroencephalography Markers, and Cognitive Outcomes.

Importance: Research evidence is mounting for the association between infant screen use and negative cognitive outcomes related to attention and executive functions. The nature, timing, and persistence of screen time exposure on neural functions are currently unknown. Electroencephalography (EEG) permits elucidation of the neural correlates associated with cognitive impairments. Objective: To examine the associations between infant screen time, EEG markers, and school-age cognitive outcomes using mediation analysis with structural equation modeling. Design, Setting, and Participants: This prospective maternal-child dyad cohort study included participants from the population-based study Growing Up in Singapore Toward Healthy Outcomes (GUSTO). Pregnant mothers were enrolled in their first trimester from June 2009 through December 2010. A subset of children who completed neurodevelopmental visits at ages 12 months and 9 years had EEG performed at age 18 months. Data were reported from 3 time points at ages 12 months, 18 months, and 9 years. Mediation analyses were used to investigate how neural correlates were involved in the paths from infant screen time to the latent construct of attention and executive functioning. Data for this study were collected from November 2010 to March 2020 and were analyzed between October 2021 and May 2022. Exposures: Parent-reported screen time at age 12 months. Main Outcomes and Measures: Power spectral density from EEG was collected at age 18 months. Child attention and executive functions were measured with teacher-reported questionnaires and objective laboratory-based tasks at age 9 years. Results: In this sample of 437 children, the mean (SD) age at follow-up was 8.84 (0.07) years, and 227 children (51.9%) were male. The mean (SD) amount of daily screen time at age 12 months was 2.01 (1.86) hours. Screen time at age 12 months contributed to multiple 9-year attention and executive functioning measures (η2, 0.03-0.16; Cohen d, 0.35-0.87). A subset of 157 children had EEG performed at age 18 months; EEG relative theta power and theta/beta ratio at the frontocentral and parietal regions showed a graded correlation with 12-month screen use (r = 0.35-0.37). In the structural equation model accounting for household income, frontocentral and parietal theta/beta ratios partially mediated the association between infant screen time and executive functioning at school age (exposure-mediator ß, 0.41; 95% CI, 0.22 to 0.59; mediator-outcome ß, -0.38; 95% CI, -0.64 to -0.11), forming an indirect path that accounted for 39.4% of the association. Conclusions and Relevance: In this study, infant screen use was associated with altered cortical EEG activity before age 2 years; the identified EEG markers mediated the association between infant screen time and executive functions. Further efforts are urgently needed to distinguish the direct association of infant screen use compared with family factors that predispose early screen use on executive function impairments.

Preschoolers' emotion reactivity and regulation: Links with maternal psychological distress and child behavior problems.

Maladaptive offspring emotion regulation has been identified as one pathway linking maternal and child psychological well-being in school-aged children. Whether such a pathway is present earlier in life still remains unclear. The present study investigated the role of preschoolers' emotion reactivity and regulation in the association between maternal psychological distress and child internalizing and externalizing problems. Children's emotion reactivity and regulation were assessed through both observed behavior and physiology. At 42 months of age, children (n = 251; 128 girls) completed a fear induction task during which their heart-rate variability was assessed and their behavior was monitored, and maternal self-reports on depressive mood and anxiety were collected. At 48 months mothers and fathers reported on their children's internalizing and externalizing problems. Higher maternal depressive mood was associated with lower child fear-related reactivity and regulation, as indexed by heart-rate variability. The latter mediated the association between higher maternal depressive mood and higher preschoolers' externalizing problems. Overall, our findings support the role of preschoolers' emotion reactivity and regulation in the relationship between maternal psychological distress and children's socio-emotional difficulties. This role may also depend on the discrete emotion to which children react or seek to regulate as, here, we only assessed fear-related reactivity and regulation.

Early Neurodevelopmental Outcomes Following Exposure to General Anesthesia in Infancy: EGAIN, a Prospective Cohort Study.

BACKGROUND: General anesthesia (GA) is known to worsen neural outcomes in animals, but human research assessing early-life GA exposure and neurodevelopment show inconsistent findings. We investigated the effects of a single GA exposure for minor surgery on the neurodevelopment of healthy children at multiple time-points, using clinical assessments along with behavioral and neurophysiological measures rarely used in human research. METHODS: GA-exposed children were a prospective cohort of 250 full-term, healthy infants who underwent GA for minor surgery before 15 months. Nonexposed children were from a separate cohort of similar age, sex, ethnicity, and maternal education. In both cohorts, clinical measures (Bayley Scales of Infant and Toddler Development-III [BSID-III] and Child Behavior Checklist [CBCL1½-5]) were assessed at 24 months, and experimental tests (memory and attentional) and neurophysiology (event-related potentials) at 6 and 18 months. RESULTS: At 24 months, there were no differences between GA-exposed and nonexposed children in the cognitive, language, motor, and socioemotional domains of the BSDI-III; however, GA-exposed children had poorer parental-reported scores in BSID-III general adaptability (94.2 vs. 99.0 [mean difference, 4.77; 97.3% confidence interval, -9.29, -0.24]; P =0.020) and poorer internalizing behavior scores on CBCL1½-5 (52.8 vs. 49.4 [mean difference, 3.35; 97.3% confidence interval, 0.15-6.55]; P =0.021). For experimental measures, GA-exposed children showed differences in 4 tests at 6 and 18 months. CONCLUSIONS: GA-exposed children did not differ from unexposed children in cognitive, language or motor outcomes at 24 months, but exhibited poorer parent-reported behavior scores. Differences in infant behavior and neurophysiology were detected at 6 and 18 months. Neurophysiological assessments may complement clinically relevant assessments to provide greater insights into neurodevelopment following early GA exposure.

Trajectories of reported sleep duration associate with early childhood cognitive development.

STUDY OBJECTIVES: Examine how different trajectories of reported sleep duration associate with early childhood cognition. METHODS: Caregiver-reported sleep duration data (n = 330) were collected using the Brief Infant Sleep Questionnaire at 3, 6, 9, 12, 18, and 24 months and Children's Sleep Habits Questionnaire at 54 months. Multiple group-based day-, night-, and/or total sleep trajectories were derived-each differing in duration and variability. Bayley Scales of Infant and Toddler Development-III (Bayley-III) and the Kaufman Brief Intelligence Test- 2 (KBIT-2) were used to assess cognition at 24 and 54 months, respectively. RESULTS: Compared to short variable night sleep trajectory, long consistent night sleep trajectory was associated with higher scores on Bayley-III (cognition and language), while moderate/long consistent night sleep trajectories were associated with higher KBIT-2 (verbal and composite) scores. Children with a long consistent total sleep trajectory had higher Bayley-III (cognition and expressive language) and KBIT-2 (verbal and composite) scores compared to children with a short variable total sleep trajectory. Moderate consistent total sleep trajectory was associated with higher Bayley-III language and KBIT-2 verbal scores relative to the short variable total trajectory. Children with a long variable day sleep had lower Bayley-III (cognition and fine motor) and KBIT-2 (verbal and composite) scores compared to children with a short consistent day sleep trajectory. CONCLUSIONS: Longer and more consistent night- and total sleep trajectories, and a short day sleep trajectory in early childhood were associated with better cognition at 2 and 4.5 years.

Attachment goes to court: child protection and custody issues.

Attachment theory and research are drawn upon in many applied settings, including family courts, but misunderstandings are widespread and sometimes result in misapplications. The aim of this consensus statement is, therefore, to enhance understanding, counter misinformation, and steer family-court utilisation of attachment theory in a supportive, evidence-based direction, especially with regard to child protection and child custody decision-making. The article is divided into two parts. In the first, we address problems related to the use of attachment theory and research in family courts, and discuss reasons for these problems. To this end, we examine family court applications of attachment theory in the current context of the best-interest-of-the-child standard, discuss misunderstandings regarding attachment theory, and identify factors that have hindered accurate implementation. In the second part, we provide recommendations for the application of attachment theory and research. To this end, we set out three attachment principles: the child's need for familiar, non-abusive caregivers; the value of continuity of good-enough care; and the benefits of networks of attachment relationships. We also discuss the suitability of assessments of attachment quality and caregiving behaviour to inform family court decision-making. We conclude that assessments of caregiver behaviour should take center stage. Although there is dissensus among us regarding the use of assessments of attachment quality to inform child custody and child-protection decisions, such assessments are currently most suitable for targeting and directing supportive interventions. Finally, we provide directions to guide future interdisciplinary research collaboration.

Neonatal brain and physiological reactivity in preschoolers: An initial investigation in an Asian sample.

Parasympathetic nervous system (PNS) activity is important to physiological regulation. Limbic structures are important in determining what information the PNS receives, potentially influencing concurrent physiological responsivity and, ultimately, shaping PNS development. Yet, whether individual differences in these structures are linked to PNS activity in early childhood remains unclear. Here, in an exploratory capacity, we examined the association between neonatal limbic structures (i.e., the left and right amygdala and hippocampus) and preschoolers' resting-state respiratory sinus arrhythmia (RSA). RSA is a measure of heart-rate variability, a physiological marker that reflects fluctuation in the PNS and is often found predictive of emotion regulation and psychological wellbeing. Data were extracted from the "Growing Up in Singapore towards Healthy Outcomes" (GUSTO) cohort (n = 73, 39 girls). Neonatal limbic volume was collected within two weeks after birth while infants were asleep. Resting-state RSA was collected during a coloring session at 42 months of age. After controlling for potential confounders, a Bonferroni-corrected significant association between neonatal left hippocampal volume and resting-state RSA emerged wherein larger hippocampal volume was associated with higher resting-state RSA. No significant associations were present between resting-state RSA and right or left amygdala, or right hippocampal volume. These findings contribute to an increasing body of evidence aiming at enhancing our understanding of neurobiological underpinnings of parasympathetic activity and modulation. Results are also discussed with reference to ideas concerning biological sensitivity to context, as both left hippocampal volume and resting-state RSA were previously found to moderate associations between adversity and psychological function.

Left lateralization of neonatal caudate microstructure affects emerging language development at 24 months.

The complex interaction between brain and behaviour in language disorder is well established. Yet to date, the imaging literature in the language disorder field has continued to pursue heterogeneous and relatively small clinical cross-sectional samples, with emphasis on cortical structures and volumetric analyses of subcortical brain structures. In our current work, we aimed to go beyond this state of knowledge to focus on the microstructural features of subcortical brain structures (specifically the caudate nucleus) in a large cohort of neonates and study its association with emerging language skills at 24 months. Variations in neonatal brain microstructure could be interpreted as a proxy for in utero brain development. As language development is highly dependent on cognitive function and home literacy environment, we also examined their effect on the caudate-language function relationship utilizing a conditional process model. Our findings suggest that emerging language development at 24 months is influenced by the degree of left lateralization of neonatal caudate microstructure, indexed by diffusion tensor imaging (DTI)-derived fractional anisotropy (FA). FA is an indirect measure of neuronal and dendritic density within grey matter structures. We also found that the caudate-language function relationship is partially mediated by cognitive function. The conditional indirect effect of left caudate FA on language composite score through cognitive function was only statistically significant at low levels of home literacy score (-1 standard deviation [SD]). The authors proposed that this may be related to 'compensatory' development of cognitive skills in less favourable home literacy environments.

Preconception origins of perinatal maternal mental health.

Perinatal maternal symptoms of depression and anxiety compromise psychosocial function and influence developmental outcomes in the offspring. The onset of symptoms remains unclear with findings that suggest a preconceptual origin. We addressed this issue with a prospective analysis of anxiety and depressive symptom profiles from preconception through to parturition. Women were recruited into a preconception study to assess (a) variation in symptom levels of depression and anxiety from pre- to post-conception and (b) if the symptom network profiles of depression and anxiety change from pre-conception to post-conception. A within-subject intraclass correlation analyses revealed that symptoms of depression or anxiety in the preconception phase strongly predicted those across pregnancy and into the early postnatal period. The symptom network analysis revealed that the symptom profiles remained largely unchanged from preconception into the second trimester. Our findings suggest that for a significant portion of women, maternal mental health remains stable from preconception into pregnancy. This finding highlights the need for early intervention studies on women's mental health to be targeted during the preconception period and to be extended across the population.

Caregiving adversity during infancy and preschool cognitive function: adaptations to context?

From a conditional adaptation vantage point, early life caregiving adversity likely enhances aspects of cognition needed to manage interpersonal threats. Yet, research examining early life care and offspring cognition predominantly relies upon experiments including affectively neutral stimuli, with findings generally interpreted as "early-life caregiving adversity is, de facto, 'bad' for cognitive performance." Here, in a Southeast Asian sample, we examined observed maternal sensitivity in infancy and cognitive performance 3 years later as preschoolers took part in three tasks, each involving both a socioemotional (SE) and non-socioemotional (NSE) version: relational memory (n = 236), cognitive flexibility (n = 203), and inhibitory control (n = 255). Results indicate the relation between early life caregiving adversity and memory performance significantly differs (Wald test = 7.67, (1), P = 0.006) depending on the SE versus NSE context, with maternal sensitivity in infancy highly predictive of worse memory for SE stimuli, and amongst girls, also predictive of better memory when NSE stimuli are used. Results concerning inhibitory control, as well as cognitive flexibility in girls, also tentatively suggest the importance of considering the SE nature of stimuli when assessing relations between the caregiving environment and cognitive performance. As not all approaches to missing data yielded similar results, implications for statistical approaches are elaborated. We conclude by considering how an adaptation-to-context framework approach may aid in designing pedagogical strategies and well-being interventions that harness pre-existing cognitive strengths.

Maternal expressions of positive emotion for children predicts children's respiratory sinus arrhythmia surrounding stress.

The aim of this study is to assess whether positive emotional exchanges (i.e., emotion coregulation) within the mother-child dyad play a protective role in children's physiological response to a distressing task. Specifically, we test whether positive emotion coregulation among mothers and their preschool-aged children is associated with children's respiratory sinus arrhythmia (RSA) at baseline, during, and following a frustration task. One hundred Singaporean mother-child dyads (Mchildage  = 3.5 years) participated in a standardized "Laughing Task" in which positive emotional constructs were measured. Children also participated in a frustration task while RSA was continuously monitored. Hierarchical linear regressions revealed that greater maternal positive emotional responses to children were associated with child RSA at baseline and in recovery from frustration, but not during frustration. These findings have implications for the important role that positive emotion responsivity from mothers may play in children's developing autonomic response systems, and underscore the need for longitudinal work on this topic.

Higher maternal plasma ß-cryptoxanthin concentration is associated with better cognitive and motor development in offspring at 2 years of age.

PURPOSE: Current literature on the roles of α-, ß-carotene and ß-cryptoxanthin in neurocognitive function has largely focused on preventing cognitive decline in older people, and less on neuro-development in children. We examined the relations of maternal plasma carotenoids concentrations with offspring cognitive development up to age 4.5 years in the Growing Up in Singapore Towards healthy Outcomes mother-offspring cohort study. METHODS: Maternal plasma α-, ß-carotene and ß-cryptoxanthin concentrations at delivery were determined by ultra-performance liquid chromatography. Children's cognition was assessed at ages 2 (Bayley Scales of Infant and Toddler Development) and 4.5 (Kaufman Brief Intelligence Test) years. Associations were examined in 419 mother-offspring pairs using linear regressions adjusting for key confounders. RESULTS: Median and interquartile range of maternal plasma concentrations (mg/L) were: α-carotene 0.052 (0.032, 0.081), ß-carotene 0.189 (0.134, 0.286), and ß-cryptoxanthin 0.199 (0.123, 0.304). In 2 years old children, higher maternal carotenoids [per standard deviation (SD) log-concentration] were positively associated with neurocognitive functions: ß-cryptoxanthin with higher scores in cognitive [ß = 0.18, (0.08, 0.28) SD], receptive language [ß = 0.17 (0.07, 0.27) SD], fine motor [ß = 0.16 (0.05, 0.26) SD], and gross motor [ß = 0.16 (0.06, 0.27) SD] scales; ß-carotene with higher cognitive score [ß = 0.17 (0.05, 0.29) SD]. No significant associations were observed with neurocognitive functions at age 4.5 years. CONCLUSION: Our study provides novel data suggesting a potential role of prenatal carotenoids, particularly ß-cryptoxanthin, on early offspring cognitive and motor development. Whether the prenatal influences sustain beyond early childhood requires further investigation in longer term studies.

Associations of maternal zinc and magnesium with offspring learning abilities and cognitive development at 4 years in GUSTO.

Objectives: Minerals deficiencies during pregnancy have been shown to be associated with poorer cognitive outcomes in offspring. This study aimed to investigate associations of maternal plasma zinc and magnesium concentrations with cognitive development in 4-year old children from the Growing Up in Singapore Towards healthy Outcome cohort.Methods: Maternal plasma zinc and magnesium concentrations were measured at 26-28 weeks' gestation. The Lollipop test of school readiness, tests of working memory, number knowledge, receptive vocabulary, and phonological awareness were performed in children at 4 years. Associations were examined in 715 mother-offspring pairs using linear regressions adjusted for key confounders.Results: Maternal plasma zinc and magnesium concentrations were 812 ± 144 µg/L and 19.9 ± 1.8 mg/L (mean±SD); 19% and 71% of mothers were zinc deficient and magnesium insufficient, respectively. After adjustment for multiple testing, higher maternal zinc concentrations (per SD increment) were associated with 0.35 higher scores in Lollipop subtest 2 of picture description and spatial identification (95% CI: 0.13, 0.58); higher maternal magnesium concentrations (per SD increment) were associated with 0.65 higher scores in Lollipop subtest 4 of letters and writing identification (95% CI: 0.23, 1.07).Discussion: No significant associations were observed for other tests, suggesting little long term influences of maternal zinc and magnesium on child's cognitive development.

Cohort profile: Singapore Preconception Study of Long-Term Maternal and Child Outcomes (S-PRESTO).

The Singapore Preconception Study of Long-Term Maternal and Child Outcomes (S-PRESTO) is a preconception, longitudinal cohort study that aims to study the effects of nutrition, lifestyle, and maternal mood prior to and during pregnancy on the epigenome of the offspring and clinically important outcomes including duration of gestation, fetal growth, metabolic and neural phenotypes in the offspring. Between February 2015 and October 2017, the S-PRESTO study recruited 1039 Chinese, Malay or Indian (or any combinations thereof) women aged 18-45 years and who intended to get pregnant and deliver in Singapore, resulting in 1032 unique participants and 373 children born in the cohort. The participants were followed up for 3 visits during the preconception phase and censored at 12 months of follow up if pregnancy was not achieved (N = 557 censored). Women who successfully conceived (N = 475) were characterised at gestational weeks 6-8, 11-13, 18-21, 24-26, 27-28 and 34-36. Follow up of their index offspring (N = 373 singletons) is on-going at birth, 1, 3 and 6 weeks, 3, 6, 12, 18, 24 and 36 months and beyond. Women are also being followed up post-delivery. Data is collected via interviewer-administered questionnaires, metabolic imaging (magnetic resonance imaging), standardized anthropometric measurements and collection of diverse specimens, i.e. blood, urine, buccal smear, stool, skin tapes, epithelial swabs at numerous timepoints. S-PRESTO has extensive repeated data collected which include genetic and epigenetic sampling from preconception which is unique in mother-offspring epidemiological cohorts. This enables prospective assessment of a wide array of potential determinants of future health outcomes in women from preconception to post-delivery and in their offspring across the earliest development from embryonic stages into early childhood. In addition, the S-PRESTO study draws from the three major Asian ethnic groups that represent 50% of the global population, increasing the relevance of its findings to global efforts to address non-communicable diseases.