Executive function in the first three years of life: Precursors, predictors and patterns

Maternal emotional availability and perinatal depressive symptoms as predictors of early childhood executive function

BACKGROUND

The interconnected effects of maternal perinatal depression and the early mother-infant relational quality on children's executive function development are crucial yet understudied. This study addresses this gap, focusing on how perinatal depressive symptoms and emotional availability at 6 months predict child executive function performance at age four, with an emphasis on the moderating role of emotional availability.

METHOD

This study included 282 mother-infant pairs recruited from the Mercy Pregnancy and Emotional Wellbeing Study, utilising repeated Edinburgh Postnatal Depression Scale measurement over the perinatal period, Emotional Availability Scales, and child executive function assessments (Shape School, NEPSY-II, Preschool Age Psychiatric Assessment, Attention Deficit Hyperactivity scale, inattentive subscale). Latent growth curve analysis incorporated controls for socioeconomic status and maternal cognitive abilities, and moderation effects were examined through multiplicative interaction terms.

RESULTS

We found that emotional availability influences children's executive function, specifically switching, motor inhibition, and inattentive symptoms, irrespective of maternal depressive symptom changes. This effect is further nuanced by emotional availability's moderating role in the association between depressive symptom change and switching.

LIMITATIONS

The study's limitations include a relatively small sample size for moderation analysis and the exclusion of paternal influences.

CONCLUSION

This study is a significant step in understanding the profound influence of maternal emotional availability in infancy on child executive function development, offering new avenues for research and, if replicated, a foundation for innovative intervention approaches.

Twenty-four-month effortful control predicts emerging autism characteristics

Longitudinal research can assess how diverging development of multiple cognitive skills during infancy, as well as familial background, are related to the emergence of neurodevelopmental conditions. Sensorimotor and effortful control difficulties are seen in infants later diagnosed with autism; this study explored the relationships between these skills and autism characteristics in 340 infants (240 with elevated familial autism likelihood) assessed at 4-7, 8-10, 12-15, 24, and 36 months. We tested: (1) the relationship between parent-reported effortful control (Rothbart's temperament questionnaires) and sensorimotor skills (Mullen Scales of Early Learning), using random intercept cross-lagged panel modelling; (2) whether household income and maternal education predicted stable individual differences in cognition; (3) sensorimotor and effortful control skills as individual and interactive predictors of parent-reported autism characteristics (Social Responsiveness Scale) at 3 years, using multiple regression; and (4) moderation of interactions by familial likelihood. Sensorimotor skills were longitudinally associated with effortful control at the subsequent measurement point from 12-15 months. Socioeconomic status indicators did not predict stable between-infant differences in sensorimotor or effortful control skills. Effortful control skills were longitudinally related to 3-year autism characteristics from the first year of life, with evidence for an interaction with sensorimotor skills at 24 months. Effects of effortful control increased with age and were particularly important for infants with family histories of autism. Results are discussed in relation to different theoretical frameworks: Developmental Cascades and Anterior Modifiers in the Emergence of Neurodevelopmental Disorders. We suggest a role for 24-month effortful control in explaining the emergent autism phenotype. RESEARCH HIGHLIGHTS: Sensorimotor skills longitudinally predicted effortful control from 12-15 months onward but effortful control did not longitudinally predict sensorimotor skills during infancy. Measures of effortful control skills taken before the age of 1 predicted continuous variation in autism characteristics at 36 months, with associations increasing in strength with age. Effortful control (measured at 12-15 and 24 months) was a stronger predictor of 36-month autism characteristics in infants with elevated familial likelihood for autism. The relationship between 24-month sensorimotor skills and 36-month autism characteristics was stronger in infants with weaker effortful control skills.

Using mindfulness-based intervention to promote executive function in young children: a multivariable and multiscale sample entropy study

Early childhood marks a pivotal period in the maturation of executive function, the cognitive ability to consciously regulate actions and thoughts. Mindfulness-based interventions have shown promise in bolstering executive function in children. This study used the functional near-infrared spectroscopy technique to explore the impact of mindfulness-based training on young children. Brain imaging data were collected from 68 children (41 boys, aged 61.8 ± 10.7 months) who were randomly assigned to either an intervention group (N = 37, aged 60.03 ± 11.14 months) or a control group (N = 31, aged 59.99 ± 10.89 months). Multivariate and multiscale sample entropy analyses were used. The results showed that: (1) brain complexity was reduced in the intervention group after receiving the mindfulness-based intervention in all three executive function tasks (ps < 0.05), indicating a more efficient neural processing mechanism after the intervention; (2) difference comparisons between the intervention and control groups showed significant differences in relevant brain regions during cognitive shifting (left dorsolateral prefrontal cortex and medial prefrontal cortex) and working memory tasks (left dorsolateral prefrontal cortex), which corroborates with improved behavioral results in the intervention group (Z = -3.674, P < 0.001 for cognitive shifting; Z = 2.594, P < 0.01 for working memory). These findings improve our understanding of early brain development in young children and highlight the neural mechanisms by which mindfulness-based interventions affect executive function. Implications for early intervention to promote young children's brain development are also addressed.

A challenge to the expected: Lack of longitudinal associations between the early caregiving environment, executive functions in toddlerhood, and self-regulation at 6 years

Previous research and theory indicate an importance of the quality of the early caregiving environment in the development of self-regulation. However, it is unclear how attachment security and maternal sensitivity, two related but distinct aspects of the early caregiving environment, may differentially predict self-regulation at school start and whether a distinction between hot and cool executive function is informative in characterizing such predictions through mediation. In a 5-year longitudinal study (n = 108), we examined these associations using measures of maternal sensitivity and attachment security at 10-12 months, executive function at 4 years, and self-regulation at 6 years. Surprisingly, and despite methodological rigor, we found few significant bivariate associations between the study variables. We found no credible evidence of a longitudinal association between maternal sensitivity or attachment security in infancy and self-regulation at 6 years, or between executive function at 4 years and self-regulation at 6 years. The lack of bivariate longitudinal associations precluded us from building mediation models as intended. We discuss our null findings in terms of their potential theoretical implications, as well as how measurement type, reliability, and validity, may play a key role in determining longitudinal associations between early caregiving factors and later self-regulation and related abilities. RESEARCH HIGHLIGHTS: The early caregiving environment has been implicated in the development of later self-regulation, which includes more basic skills, such as hot and cool executive functions (EF). In a 5-year longitudinal study, with a sample of 108 children, we rigorously measured aspects of early caregiving, EF, and self-regulation. We found no significant longitudinal associations between early caregiving and self-regulation at 6 years, nor between EF at 4 years and self-regulation at 6 years. These null results highlight the complexity of modeling self-regulation development and raise critical questions about general methodological conventions within self-regulation development research.

Executive functioning skills and their environmental predictors among pre-school aged children in South Africa and The Gambia

Executive functions (EFs) in early childhood are predictors of later developmental outcomes and school readiness. Much of the research on EFs and their psychosocial correlates has been conducted in high-income, minority world countries, which represent a small and biased portion of children globally. The aim of this study is to examine EFs among children aged 3-5 years in two African countries, South Africa (SA) and The Gambia (GM), and to explore shared and distinct predictors of EFs in these settings. The SA sample (N = 243, 51.9% female) was recruited from low-income communities within the Cape Town Metropolitan area. In GM, participants (N = 171, 49.7% female) were recruited from the rural West Kiang region. EFs, working memory (WM), inhibitory control (IC) and cognitive flexibility (CF), were measured using tablet-based tasks. Associations between EF task performance and indicators of socioeconomic status (household assets, caregiver education) and family enrichment factors (enrichment activities, diversity of caregivers) were assessed. Participants in SA scored higher on all EF tasks, but children in both sites predominantly scored within the expected range for their age. There were no associations between EFs and household or familial variables in SA, except for a trend-level association between caregiver education and CF. Patterns were similar in GM, where there was a trend-level association between WM and enrichment activities but no other relationships. We challenge the postulation that children in low-income settings have poorer EFs, simply due to lower socioeconomic status, but highlight the need to identify predictors of EFs in diverse, global settings. RESEARCH HIGHLIGHTS: Assessed Executive Functioning (EF) skills and their psychosocial predictors among pre-school aged children (aged 3-5 years) in two African settings (The Gambia and South Africa). On average, children within each setting performed within the expected range for their age, although children in South Africa had higher scores across tasks. There was little evidence of any association between socioeconomic variables and EFs in either site. Enrichment activities were marginally associated with better working memory in The Gambia, and caregiver education with cognitive flexibility in South Africa, both associations were trend-level significance.

Age Three: Milestone in the Development of Cognitive Flexibility

Although the cognitive flexibility (CF) of preschool children has been extensively studied, the development of CF in children around three years old is unclear. This study aimed to investigate the CF of three-year-olds in a stepwise rule-induction task (sRIT) comprising nine steps in which children are encouraged to switch attention to a new rule and then implicitly inhibit the old one. A pair of boxes was displayed at each step, and children aged 2.5 to 3.5 years were asked to select the target. When children learned a rule (e.g., the shape rule), they were encouraged to switch rules through negative feedback. The results showed that most children (81.10%) passed at least one of the two sets of the sRIT, and children over the age of three years performed better than those under three years. Additionally, a positive correlation existed between rule switching and rule generalization, whereby the old rule was implicitly inhibited. These findings indicate that age three might be a milestone in the development of CF, and inhibitory control might play a vital role in rule switching.

Executive functions abilities in preschool-age children are negatively related to parental EF, screen-time and positively related to home literacy environment: an EEG study

Environmental factors such as Home Literacy Environment (HLE), screen time, and parental executive functions (EF) may influence the development of the child's EF. The purpose of this study was to determine the effect of these factors on behavioral and neurobiological measures of EF in 4-year-old children. Electroencephalogram (EEG) data were collected while children performed the Attention Network Task (ANT), showing a smaller difference between incongruent and congruent conditions is related to better EF abilities. Data were analyzed using an Event-Related Potential (ERP) technique focusing on the N200 and P300 components (reflecting executive control and orienting attention, respectively). N200 and P300 differences (delta) between amplitudes and latencies for the incongruent and congruent conditions were computed and correlated with child EF skills, HLE, screen exposure, and parental EF. Screen exposure was associated with lower EF in children and their parents. Additionally, smaller differences between N200 amplitudes and latencies for the incongruent vs. congruent conditions were associated with higher HLE scores. In contrast, greater differences between P300 amplitudes and latencies were related to longer screen time. HLE was positively associated with EF's neurobiological (EEG) and behavioral measures, and screen time was negatively associated with these measures. This study also highlights the important relationship between parental EF (i.e., family predisposition) and EF's neurobiological and behavioral measures in their children.

Cognitive control in infancy: Attentional predictors using a tablet-based measure

Cognitive control is a predictor of later-life outcomes and may underpin higher order executive processes. The present study examines the development of early cognitive control during the first 24-month. We evaluated a tablet-based assessment of cognitive control among infants aged 18- and 24-month. We also examined concurrent and longitudinal associations between attentional disengagement, general cognitive skills and cognitive control. Participants (N = 60, 30 female) completed the tablet-task at 18- and 24-month of age. Attentional disengagement and general cognitive development were assessed at 5-, 8-, 12-, 18- and 24-month using an eye-tracking measure and the Mullen Scales of Early Learning (MSEL), respectively. The cognitive control task demonstrated good internal consistency, sensitivity to age-related change in performance and stable individual differences. No associations were found between infant cognitive control and MSEL scores longitudinally or concurrently. The eye-tracking task revealed that slower attentional disengagement at 8-month, but faster disengagement at 18-month, predicted higher cognitive control scores at 24-month. This task may represent a useful tool for measuring emergent cognitive control. The multifaceted relationship between attention and infant cognitive control suggests that the rapid development of the attentional system in infancy results in distinct attentional skills, at different ages, being relevant for cognitive control development.

Conceptualizing avoidant/restrictive food intake disorder via an executive functioning lens

Avoidant/restrictive food intake disorder (ARFID) is a heterogeneous disorder wherein restrictive eating is primarily attributed to non-shape/weight-based reasons (e.g., sensory sensitivity) that empirical research continues to explore. Mounting evidence suggests that ARFID often presents alongside neurodevelopmental diagnoses (NDs) or divergent neurodevelopment broadly. Executive functioning (EF) differences often characterize divergent neurodevelopmental trajectories. Additionally, restrictive eating in anorexia nervosa has been conceptualized as related to EF factors (e.g., set shifting). Given the neurodevelopmental phenotype that may be associated with ARFID and the role of EF in anorexia nervosa, this paper proposes EF as a potentially important, yet understudied factor in ARFID pathology. We posit that various observed ARFID behavioral/cognitive tendencies can be conceptualized in relation to EF differences. We contextualize commonly observed ARFID presentations within "core" EF components (i.e., cognitive flexibility, working memory, inhibitory control), leading to hypotheses about EF in ARFID. Finally, we offer additional considerations/directions for future research on EF in ARFID. Increased research on EF in ARFID is needed to consider this potential common factor in the etiology and maintenance of this heterogeneous disorder. We aim to promote further consideration of EF in ARFID etiology, maintenance, and treatment-outcome research. PUBLIC SIGNIFICANCE: This article proposes that aspects of executive functioning (EF) may play a role in the onset and maintenance of avoidant/restrictive food intake disorder (ARFID), although this notion is largely untested by existing research. Further research on the role of EF in ARFID may assist with refining models and treatments for this heterogeneous disorder.

Attention control in preterm and term 5-month-old infants: Cross-task stability increases with gestational age

Cross-task stability refers to performance consistency across different settings and measures of the same construct. Cross-task stability can help us understand developmental processes, including how risks such as preterm birth affect outcomes. We investigated cross-task stability of attention control in 32 preterm and 39 term infants. All infants had the same chronological age at time of testing (5 months) but varied in gestational age (GA) at birth (30-42 weeks). Infants completed an experimental attention following task with a researcher and a naturalistic play observation with their mothers. Both preterm and term infants demonstrated attention following in the experimental task. GA and flexibility of attention were related: the likelihood of no turn trials decreased with increasing GA. To evaluate cross-task stability, we compared attention performance in the experimental and naturalistic settings. Flexible attention shifts on the experimental task were positively related to attention to objects in the naturalistic observation. Furthermore, the association between flexible attention shifts on the experimental task and attention to objects in the naturalistic observation was moderated by GA. Our study provides initial evidence that the consolidation of attention control increases with GA. These findings highlight the value of comparing experimental and observational measures of attention.

The Development of Cognitive Control in Preschoolers and Kindergarteners: The Case of Post-Error Slowing and Delayed Disinhibition

This study aimed to investigate two specific behavioral manifestations of the executive attention systems in preschoolers and kindergarteners, beyond the unique contribution of intelligence. We tested post-error slowing [RT¯Post-error trial-RT¯Not post-error trial] as a marker of reactive control and delayed disinhibition as a novel marker for proactive control. One hundred and eighty preschool- and kindergarten-aged children, as well as their mothers (final sample: 155 children and 174 mothers), performed an adapted task based on Go/NoGo and Stroop-like paradigms-the emotional day-night task. The children showed reliable post-error slowing and delayed disinhibition (mean size effects of 238.18 ms and 58.31 ms, respectively), while the adult size effects were 40-50% smaller. The post-error slowing effect was present for both sexes in all the tested ages, while the delayed disinhibition effect was present only for girls. Both effects showed large individual differences that became smaller in adulthood. Our findings emphasize the earlier maturation of reactive control compared to proactive control, and the earlier maturation of proactive cognitive control in girls compared to boys.

A preliminary investigation of epigenome-wide DNA methylation and temperament during infancy

This study provides preliminary evidence for an epigenetic architecture of infant temperament. At 12 months of age, blood was collected and assayed for DNA methylation and maternally reported infant temperament was assessed using the Infant Behavior Questionnaire in 67 mother-infant dyads. Epigenome-wide analyses showed that the higher order temperament dimensions Surgency and Negative Affect were associated with DNA methylation. The epigenetic signatures of Surgency and Negative Affect were situated at genes involved in synaptic signaling and plasticity. Although replication is required, these results are consistent with a biologically based model of temperament, create new avenues for hypothesis-driven research into epigenetic pathways that underlie individual differences in temperament, and demonstrate that infant temperament has a widespread epigenetic signature in the methylome.

Predictors of executive function among 2 year olds from a Thai birth cohort

Executive function (EF) is a critical skill for academic achievement. Research on the psychosocial and environmental predictors of EF, particularly among Southeast Asian, agricultural, and low income/rural populations, is limited. Our longitudinal study explored the influence of agricultural environmental, psychosocial, and temperamental factors on children's emerging EF. Three-hundred and nine farm worker women were recruited during the first trimester of pregnancy. We evaluated the effects of prenatal insecticide exposure and psychosocial factors on "cool" (i.e., cognitive: A-not-B task, looking version) and "hot" EF (i.e., affective, response inhibition) measures of emerging EF. Maternal urine samples were collected monthly during pregnancy, composited, and analyzed for dialkylphosphate (DAP) metabolites of organophosphate insecticides. Psychosocial factors included socioeconomic status, maternal psychological factors, and quality of mother-child behavioral interactions. Backward stepwise regressions evaluated predictors of children's EF at 12 (N = 288), 18 (N = 277) and 24 (N = 280) months of age. We observed different predictive models for cool EF, as measured by A-not-B task, vs. hot EF, as measured by response inhibition tasks. Report of housing quality as a surrogate for income was a significant predictor of emerging EF. However, these variables had opposite effects for cool vs. hot EF. More financial resources predicted better cool EF performance but poorer hot EF performance. Qualitative findings indicate that homes with fewer resources were in tribal areas where children must remain close to an adult for safety reasons. This finding suggests that challenging physical environments (e.g., an elevated bamboo home with no electricity or running water), may contribute to development of higher levels of response inhibition through parental socialization methods that emphasize compliance. Children who tended to show more arousal and excitability, and joy reactivity as young infants in the laboratory setting had better cognitive performance. In contrast, maternal emotional availability was a significant predictor of hot EF. As expected, increased maternal exposure to pesticides during pregnancy was associated with worse cognitive performance but was not associated with inhibitory control. Identifying risk factors contributing to the differential developmental pathways of cool and hot EF will inform prevention strategies to promote healthy development in this and other unstudied rural, low income Southeast Asian farming communities.

Attention control in autism: Eye-tracking findings from pre-school children in a low- and middle-income country setting

LAY ABSTRACT

The development of cognitive processes, such as attention control and learning, has been suggested to be altered in children with a diagnosis of autism spectrum disorder. However, nearly all of our understanding of the development of these cognitive processes comes from studies with school-aged or older children in high-income countries, and from research conducted in a controlled laboratory environment, thereby restricting the potential generalisability of results and away from the majority of the world's population. We need to expand our research to investigate abilities beyond these limited settings. We address shortcomings in the literature by (1) studying attention control and learning in an understudied population of children in a low- and middle-income country setting in India, (2) focusing research on a critical younger age group of children and (3) using portable eye-tracking technology that can be taken into communities and healthcare settings to increase the accessibility of research in hard-to-reach populations. Our results provide novel evidence on differences in attention control and learning responses in groups of children with and without a diagnosis of autism spectrum disorder. We show that learning responses in children that we assessed through a portable eye-tracking task, called the 'antisaccade task', may be specific to autism. This suggests that the methods we use may have the potential to identify and assess autism-specific traits across development, and be used in research in low-resource settings.

How does sensitivity influence early executive function? A critical review on hot and cool processes

There is compelling evidence that the quality of caregiver-child interactions during toddlerhood and the preschool years supports the development of executive function (EF) (Bernier et al., 2010; 2015; 2016; Fay-Stammbach et al., 2014; Geeraerts et al., 2021). Based on such findings, we make the case herein that sensitivity may be one of the most important dimensions of parenting contributing to early EF. In the present article, we will review empirical evidence, integrating findings from a wide range of scientific disciplines - cognitive psychology, neuroscience, and developmental psychopathology - and present theoretical ideas about how two contexts of sensitive caregiving - i.e. sensitivity to distress and non-distress cues - may be contributing differently to hot and cool EF development. Implications for future investigations on the environmental contributors of early EF, and its mechanisms, are discussed.

Kia Tīmata Pai (Best Start): a study protocol for a cluster randomised trial with early childhood teachers to support children's oral language and self-regulation development

INTRODUCTION

Oral language skills are associated with children's later self-regulation and academic skills; in turn, self-regulation in early childhood predicts successful functioning later in life. The primary objective of this study is to evaluate the separate and combined effectiveness of an oral language intervention (Enhancing Rich Conversations, ENRICH) and a self-regulation intervention (Enhancing Neurocognitive Growth with the Aid of Games and Exercise, ENGAGE) with early childhood teachers and parents for children's oral language, self-regulation and academic functioning.

METHODS AND ANALYSIS

The Kia Tīmata Pai (Best Start) study is a cluster randomised controlled trial with teachers and children in approximately 140 early childhood centres in New Zealand. Centres are randomly assigned to receive either oral language intervention only (ENRICH), self-regulation intervention only (ENGAGE), both interventions (ENRICH+ENGAGE) or an active control condition. Teachers' and parents' practices and children's oral language and self-regulation development are assessed at baseline at age 1.5 years and approximately every 9 months to age 5, and academic performance at age 6. Teacher-child interactions will also be videotaped each year in a subset of the centres. Children's brain and behaviour development and parent-child interactions will be assessed every 6 months to age 6 years in a subgroup of volunteers.

ETHICS AND DISSEMINATION

The Kia Tīmata Pai trial and the two substudies (Video Project; Brain and Behaviour Development) have been approved by the University of Otago Human Ethics Committee (Health; H20/116), and reviewed for cultural responsiveness by: the Ngāi Tahu Research Committee (University of Otago), the Māori Advisory Group (University of Auckland, Liggins Institute) and an internal cultural advisory group. Results will be disseminated in international and national peer-reviewed academic journals and communicated to local, national and international organisations serving early childhood teachers, parents and young children. Data will be available via communication with the corresponding author.

TRIAL REGISTRATION NUMBER

ACTRN12621000845831.

The longitudinal contributions of child language, negative emotionality, and maternal positive affect on toddler executive functioning development

Executive functions (EF) develop rapidly across early childhood and play a prominent role in promoting adaptive outcomes later in development. Although the existing literature suggests that the development of early EF is sensitive to the influence of intrinsic and extrinsic factors, limited research has examined the joint contributions of multiple child and contextual factors in infancy/toddlerhood. The purpose of our longitudinal study was therefore to identify early environmental, behavioral, biologically-based factors that influence children's EF outcomes in late toddlerhood. Participants included 409 mother-child dyads (209 girls) and the data was collected across children's first three postnatal years. Parent-report measures were used to assess infant negative affectivity (5-months; IBQ-R) and toddler language (age 2; MCDI), and both maternal positive affect (5-months) and toddler frustration (age 2) were coded during mother-child interaction tasks. A battery of behavioral tasks was used to measure child EF in late toddlerhood (age 3). After controlling for maternal education (a proxy for children's socio-economic environment), path analysis indicated that both infant and maternal affect at 5-months directly predicted toddlers' language skills and frustration expression at age 2. Toddler language (but not frustration) also predicted child performance on multiple EF tasks at age 3. Finally, 5-month infant and maternal affect indirectly predicted age 3 EF via age 2 language. Our results identify language as a mechanism through which children's early caregiving environment influences their EF development. Taken together, these findings illustrate the importance of applying a biopsychosocial perspective to the examination of early childhood EF development.

The Interplay between Socioeconomic Status, Parenting and Temperament Predicts Inhibitory Control at Two Years of Age

This paper investigates the interplay between environmental factors (socioeconomic status (SES) and parenting) and temperament in the development of inhibitory control (IC) at 2 years of age. We administered to toddlers (n = 59) a delay of gratification task which measures IC in the context of self-regulation. Parents reported their toddlers' temperament, parenting strategies, and SES. We hypothesized that poorer IC would be associated with more reactive temperament, less effortful control, lower SES and inconsistent/coercive parenting practices. Finally, we explored the interaction between temperament, parenting and SES. We found that both coercive parenting and low-SES were negatively correlated to IC at the age of 2 years. Temperamental reactivity was unrelated to IC, whereas temperamental effortful control (EC) was positively associated with IC. Results revealed a moderation effect of EC on the influence of coercive parenting and SES in toddlers' IC. Toddlers from lower SES backgrounds and with lower EC were more affected by inconsistent/coercive parenting practices and showed the poorest IC. In contrast, toddlers exhibiting high and average levels of EC seemed to be protected from the detrimental effect of low-SES and inconsistent/coercive parenting on IC. These results suggest that strengthening toddlers' EC and improving parents' parenting skills might be especially relevant for the development of IC in the context of self-regulation, particularly by preventing self-regulatory problems in children from socioeconomically deprived environments. Future studies with larger samples, focusing on populations from severe socioeconomically deprived environments, or intervention studies will be needed in order to confirm and expand our findings.

Executive functioning in preschoolers with 22q11.2 deletion syndrome and the impact of congenital heart defects

BACKGROUND

Executive functioning (EF) is an umbrella term for various cognitive functions that play a role in monitoring and planning to effectuate goal-directed behavior. The 22q11.2 deletion syndrome (22q11DS), the most common microdeletion syndrome, is associated with a multitude of both somatic and cognitive symptoms, including EF impairments in school-age and adolescence. However, results vary across different EF domains and studies with preschool children are scarce. As EF is critically associated with later psychopathology and adaptive functioning, our first aim was to study EF in preschool children with 22q11DS. Our second aim was to explore the effect of a congenital heart defects (CHD) on EF abilities, as CHD are common in 22q11DS and have been implicated in EF impairment in individuals with CHD without a syndromic origin.

METHODS

All children with 22q11DS (n = 44) and typically developing (TD) children (n = 81) were 3.0 to 6.5 years old and participated in a larger prospective study. We administered tasks measuring visual selective attention, visual working memory, and a task gauging broad EF abilities. The presence of CHD was determined by a pediatric cardiologist based on medical records.

RESULTS

Analyses showed that children with 22q11DS were outperformed by TD peers on the selective attention task and the working memory task. As many children were unable to complete the broad EF task, we did not run statistical analyses, but provide a qualitative description of the results. There were no differences in EF abilities between children with 22q11DS with and without CHDs.

CONCLUSION

To our knowledge, this is the first study measuring EF in a relatively large sample of young children with 22q11DS. Our results show that EF impairments are already present in early childhood in children with 22q11DS. In line with previous studies with older children with 22q11DS, CHDs do not appear to have an effect on EF performance. These findings might have important implications for early intervention and support the improvement of prognostic accuracy.

Influence of the environment on the early development of attentional control

The control of visual attention is key to learning and has a foundational role in the development of self-regulated behavior. Basic attention control skills emerge early in life and show a protracted development along childhood. Prior research suggests that attentional development is influenced by environmental factors in early and late childhood. Although, much less information is available about the impact of the early environment on emerging endogenous attention skills during infancy. In the current study we aimed to test the impact of parental socioeconomic status (SES) and home environment (chaos) in the emerging control of orienting in a sample of typically-developing infants. A group of 142 (73 female) 6-month-old infants were longitudinally tested at 6, 9 (n = 122; 60 female) and 16-18 (n = 91; 50 female) months of age using the gap-overlap paradigm. Median saccade latency (mdSL) and disengagement failure (DF) were computed as dependent variables for both overlap and gap conditions. Also, composite scores for a Disengagement Cost Index (DCI) and Disengagement Failure Index (DFI) were computed considering mdSL and DF of each condition, respectively. Families reported SES and chaos in the first and last follow-up sessions. Using Linear Mixed Models with Maximum Likelihood estimation (ML) we found a longitudinal decrease in mdSL in the gap but not in the overlap condition, while DF decreased with age independently of the experimental condition. Concerning early environmental factors, an SES index, parental occupation and chaos at 6 months were found to show a negative correlation with DFI at 16-18 months, although in the former case it was only marginally significant. Hierarchical regression models implementing ML showed that both SES and chaos at 6 months significantly predicted a lower DFI at 16-18 months. Results show a longitudinal progression of endogenous orienting between infancy and toddlerhood. With age, an increased endogenous control of orienting is displayed in contexts where visual disengagement is facilitated. Visual orienting involving attention disengagement in contexts of visual competition do not show changes with age. Moreover, these attentional mechanisms of endogenous control seem to be modulated by early experiences of the individual with the environment.

The mediating role of neurocognitive functions in the relation between physical competencies and academic achievement of primary school children

Previous studies into associations between physical, neurocognitive and academic skills have reported inconsistent results. This study aimed to get more insight into these relations by examining all three domains simultaneously, testing a complete mediational model including measures of physical competencies (cardiovascular fitness and motor skills), neurocognitive skills (attention, information processing, and core executive functions), and academic achievement (reading, mathematics, and spelling). Dutch primary school students (n = 891, 440 boys, mean age 9.17 years) were assessed on the Shuttle Run Test (cardiovascular fitness), items of the Körperkoordinationstest für Kinder and Bruininks-Oseretsky Test-II (fundamental motor skills), computerized neurocognitive tests, and standardized academic achievement tests. A multilevel structural equation model showed that physical competencies were only indirectly related to academic achievement, via specific neurocognitive functions depending on the academic domain involved. Results provide important implications, highlighting the importance of well-developed physical competencies in children.

Does parental autonomy support mediate the relation between parent and infant executive function? A study of mothers and fathers in the Netherlands and China

Parenting skills, such as Autonomy Support (AS), have been proposed as a potential mechanism explaining the intergenerational contiguity of Executive Function (EF). However, few studies have focused on mothers and fathers among non-Western families. The current study investigated the role of maternal and paternal AS in the relation between parental EF and infant EF at 14 months of age among 123 Dutch and 63 Chinese first-time mothers and fathers and their infants. Multiple-group structural equation models were built for mothers and fathers separately with country as a grouping variable. Results showed that parental AS did not mediate the relation between parent EF and infant EF at 14 months. Mean-level differences were found in parental AS, maternal EF, and infant inhibition across countries, while no country differences were found in the relation between parent EF, AS and infant EF. Our findings suggested that individual differences in early EF may not be stable enough to be reliably predicted from parental factors across the Netherlands and China.

Predicting behavioral and brain markers of inhibitory control at preschool age from early measures of executive attention

Background

Inhibitory control (IC) is the ability to prevent prepotent responses when inappropriate. Longitudinal research on IC development has mainly focused on early childhood and adolescence, while research on IC development in the first years of life is still scarce. To address this gap in the literature, we explored the association between executive attention (EA) and elementary forms of IC in infancy and toddlerhood, with individual differences in IC later at 5 years of age.

Method

We conducted a five-wave longitudinal study in which children's EA and IC (n = 96) were tested at the age of 9 and 16 months and 2, 3, and 5 years. Children performed various age-appropriate EA and IC tasks in each wave, measuring inhibition of attention, endogenous control of attention, inhibition of the response, and conflict inhibition. At 5 years of age, IC was measured with a Go/No-go task while recording event-related potentials. After correlation analyses, structural equation model analyses were performed to predict IC at 5 years of age from EA and early IC measures.

Results

The results revealed that EA at 9 months predicted IC measures at 2 years of age. Likewise, measures of IC at 2 years predicted performance on the Go/No-go task at behavioral and neural levels. No direct association was found between EA at 9 months and IC at 5 years of age. We further observed that some EA and IC measures were not associated across time.

Conclusion

As we expected, EA skills in infancy and toddlerhood were related to better performance of children on IC tasks, toghether with a more mature inhibition-related brain functioning. Altogether, the results indicate that IC in early childhood could be predicted from EA and IC at 9 months and 2 years of age and suggest that the early emergence of IC relies on the development of particular EA and basic IC skills. However, some discontinuities in the longitudinal development of IC are observed in the first 5 years of life. These findings provide further support for the hierarchical model of IC development.

Executive function profiles of preschool children with autism spectrum disorder and attention-deficit/hyperactivity disorder: A systematic review

Background

Autism Spectrum Disorder (ASD) and Attention-Deficit/Hyperactivity Disorder (ADHD) are both associated with differences in Executive Functioning (EF). There is lack of clarity around the specificity or overlap of EF differences in early childhood when both disorders are first emerging.

Method

This systematic review aims to delineate preschool EF profiles by examining studies comparing the EF profiles of children with and without ASD or ADHD. Five electronic databases were systematically searched (last search in May 2022) to identify published, quantitative studies of global and specific EF (Inhibition, Shifting, Working Memory (WM), Planning and Attentional Control), comparing children aged 2-6 with a diagnosis of ASD or ADHD to peers without ASD or ADHD.

Results

Thirty-one empirical studies (10 ADHD and 21 ASD studies) met criteria for inclusion. EF profiles in preschool ASD were characterised by consistent Shifting, and, in most cases, Inhibition impairments. ADHD studies consistently reported impairments in Inhibition and Planning, and in most cases WM. Findings with regards to sustained Attention and Shifting in ADHD and WM and Planning in ASD were mixed.

Conclusions

Overall, current evidence indicates overlap but also some specificity in EF impairments in preschool ASD and ADHD. There were differences in the degree to which individual domains were impaired, with Shifting more consistently impaired in ASD, and Inhibition, WM and Planning in ADHD. Methodological issues and differences in methods of outcome measurement could potentially underlie mixed findings, as informant-based measures revealed more robust EF impairments than laboratory-based tasks.

Acquisition of cognitive and communication milestones in infants with Down syndrome

BACKGROUND

Understanding the timing of developmental milestones in typical and clinical populations facilitates intervention planning and the early detection of risk for co-occurring conditions. Normative timing of developmental milestone achievement has been established for typically developing children. However, there is little information regarding the timing of cognitive and communication skill acquisition in young children with Down syndrome (DS). The objectives of this study are to (1) provide foundational information regarding the timing of cognitive and communication skill acquisition in infants with DS and (2) facilitate the early identification of infants with risk for co-occurring conditions.

METHOD

Seventy-four infants with DS (age range: 4-18 months) completed the Bayley Scales of Infant Development-III (Bayley 2006). Individual items from the cognitive and communication scales were selected for analysis. Parents provided information regarding their infant's developmental and family history.

RESULTS

The percentage of infants who attained each skill was calculated within 2-month age bands. For infants who did not show skill acquisition within each age band, the rates of prematurity, heart defects, corrective heart surgery and significant illness were calculated as well.

CONCLUSIONS

This study provides foundational information that can contribute to the formulation of a developmental schedule for cognitive and language milestone acquisition in infants with DS.

Goal choice in preschoolers is influenced by context, cognitive flexibility, and metacognition

Introduction

Goal choice is one of the first, and most important, steps in self-regulated learning (SRL). It is particularly challenging for young children (before 5–6 years), who tend to rely on available environmental cues, which makes their goals fragile because of the instability and variability of the environment. Therefore, it can be assumed that the conditions under which a task is performed may influence a child’s learning goal choice. Moreover, adapting to constraints involves control capacities provided by executive functions (EF) and metacognition.

Methods

The main purpose of this study was to determine factors that influence the way preschoolers choose a learning goal during the first step of SRL. We tested whether adding constraints to perform a task may influence the choice of the procedure that a child aims to learn to perform this task. We also examined the role of cognitive flexibility and metacognition in goal selection in the face of these changes, and tested the influence of change over time, comparing participants’ performance at two points in the school year. One hundred 4-year-olds were asked to perform a jigsaw puzzle task under two conditions: predictable vs. unpredictable environmental change. Individual levels of cognitive flexibility and metacognition were also measured.

Results

The results show that only a predictable change, but not an unpredictable one, leaded children to change their learning goals. Furthermore, when participants were faced with an unpredictable change, metacognition and cognitive flexibility significantly predicted learning goal change. Results are discussed regarding the development of SRL, flexibility, and metacognition. Educational suggestions are proposed.

Highlights

– The choice of a learning goal by a preschooler is influenced by the conditions of task performance and environmental cues. Facing a predictable change is more disruptive to children before the age of 4.5, and more likely to cause them to change their goal.

– A shift is observed, from age 4 and during the school year, from a perceptual to a conceptual level of processing.

– Cognitive flexibility and metacognition also determine learning goal choice in preschoolers, but only in front of unpredictable changes.

Developmental links between executive function and emotion regulation in early toddlerhood

Developmental associations between poor executive function (EF) and problem behaviors in toddlerhood indicate that the interplay between cognition and affect begins very early in life (Hughes, Devine, Mesman, & Blair, 2020). However, very few longitudinal studies of toddlers have included direct measures of both EF and emotion regulation (ER). In addition, while models of ER highlight the importance of situational contexts (e.g., Miller, McDonough, Rosenblum, Sameroff, 2005), existing work is limited by a heavy reliance on lab-based observations of mother-child dyads. Addressing these twin gaps, the current study of 197 families included video-based ratings of ER in toddlers' dyadic play with both mothers and fathers at each of two time-points (14- and 24-months), with parallel measures of EF being gathered in each home visit. Our cross-lagged analyses showed that EF at 14 months predicted ER at 24 months, but this association was limited to observations of toddlers with mothers. It was also asymmetric: ER at 14 months did not predict EF at 24 months. These findings support co-regulation models of early ER and highlight the predictive utility of very early individual differences in EF.

Psychometric properties of the Teenage Executive Functioning Inventory in a Turkish sample of adolescents: deficits in working memory and inhibition among adolescents

The Teenage Executive Functioning Inventory (TEXI) is a measurement tool that consists of two subscales, working memory and inhibition, and allows both self and parent rating. This study aimed to examine the psychometric properties of the Turkish version of TEXI in a sample of 184 parents and 476 adolescents aged 11 and 18 years and to measure the relationship between executive functions and mental health problems, including attention deficit hyperactivity disorder and major depressive disorder and anxiety disorders. Confirmatory factor analyses showed acceptable/good fit indices and confirmed the two-factor structure for both the adolescent and parent forms. Test-retest results and Cronbach's alpha coefficient showed that the scale had high reliability. The results also showed that deficits in executive functions were associated with various mental health problems in adolescents. The findings demonstrated that a Turkish translation of the TEXI is a valid and reliable tool for evaluating the executive functions of adolescents.

Anticipation across modalities in children and adults: Relating anticipatory alpha rhythm lateralization, reaction time, and executive function

The development of the ability to anticipate-as manifested by preparatory actions and neural activation related to the expectation of an upcoming stimulus-may play a key role in the ontogeny of cognitive skills more broadly. This preregistered study examined anticipatory brain potentials and behavioral responses (reaction time; RT) to anticipated target stimuli in relation to individual differences in the ability to use goals to direct action (as indexed by measures of executive function; EF). A cross-sectional investigation was conducted in 40 adults (aged 18-25 years) and 40 children (aged 6-8 years) to examine the association of changes in the amplitude of modality-specific alpha-range rhythms in the electroencephalogram (EEG) during anticipation of lateralized visual, tactile, or auditory stimuli with inter- and intraindividual variation in RT and EF. Children and adults exhibited contralateral anticipatory reductions in the mu rhythm and the visual alpha rhythm for tactile and visual anticipation, respectively, indicating modality and spatially specific attention allocation. Variability in within-subject anticipatory alpha lateralization (the difference between contralateral and ipsilateral alpha power) was related to single-trial RT. This relation was more prominent in adults than in children, and was not apparent for auditory stimuli. Multilevel models indicated that interindividual differences in anticipatory mu rhythm lateralization contributed to the significant association with variability in EF, but this was not the case for visual or auditory alpha rhythms. Exploratory microstate analyses were undertaken to cluster global field power (GFP) into a distribution-free temporal analysis examining developmental differences across samples and in relation to RT and EF. Anticipation is suggested as a developmental bridge construct connecting neuroscience, behavior, and cognition, with anticipatory EEG oscillations being discussed as quantifiable and potentially malleable indicators of stimulus prediction.

Infant excitation/inhibition balance interacts with executive attention to predict autistic traits in childhood

BACKGROUND

Autism is proposed to be characterised by an atypical balance of cortical excitation and inhibition (E/I). However, most studies have examined E/I alterations in older autistic individuals, meaning that findings could in part reflect homeostatic compensation. To assess the directionality of effects, it is necessary to examine alterations in E/I balance early in the lifespan before symptom emergence. Recent explanatory frameworks have argued that it is also necessary to consider how early risk features interact with later developing modifier factors to predict autism outcomes.

METHOD

We indexed E/I balance in early infancy by extracting the aperiodic exponent of the slope of the electroencephalogram (EEG) power spectrum ('1/f'). To validate our index of E/I balance, we tested for differences in the aperiodic exponent in 10-month-old infants with (n = 22) and without (n = 27) neurofibromatosis type 1 (NF1), a condition thought to be characterised by alterations to cortical inhibition. We then tested for E/I alterations in a larger heterogeneous longitudinal cohort of infants with and without a family history of neurodevelopmental conditions (n = 150) who had been followed to early childhood. We tested the relevance of alterations in E/I balance and our proposed modifier, executive attention, by assessing whether associations between 10-month aperiodic slope and 36-month neurodevelopmental traits were moderated by 24-month executive attention. Analyses adjusted for age at EEG assessment, sex and number of EEG trials.

RESULTS

Infants with NF1 were characterised by a higher aperiodic exponent, indicative of greater inhibition, supporting our infant measure of E/I. Longitudinal analyses showed a significant interaction between aperiodic slope and executive attention, such that higher aperiodic exponents predicted greater autistic traits in childhood, but only in infants who also had weaker executive functioning abilities.

LIMITATIONS

The current study relied on parent report of infant executive functioning-type abilities; future work is required to replicate effects with objective measures of cognition.

CONCLUSIONS

Results suggest alterations in E/I balance are on the developmental pathway to autism outcomes, and that higher executive functioning abilities may buffer the impact of early cortical atypicalities, consistent with proposals that stronger executive functioning abilities may modify the impact of a wide range of risk factors.

Habitual night waking associates with dynamics of waking cortical theta power in infancy

The implications of the substantial individual differences in infant sleep for early brain development remain unclear. Here, we examined whether night sleep quality relates to daytime brain activity, operationalized through measures of EEG theta power and its dynamic modulation, which have been previously linked to later cognitive development. For this longitudinal study, 76 typically developing infants were studied (age: 4-14 months, 166 individual study visits) over the course of 6 months with one, two, three, or four lab visits. Habitual sleep was measured with a 7-day sleep diary and actigraphy, and the Brief Infant Sleep Questionnaire. Twenty-channel EEG was recorded while infants watched multiple rounds of videos of women singing nursery rhymes; oscillatory power in the theta band was extracted. Key metrics were average theta across stimuli and the slope of change in theta within the first novel movie. Both objective and subjective sleep assessment methods showed a relationship between more night waking and higher overall theta power and reduced dynamic modulation of theta over the course of the novel video stimuli. These results may indicate altered learning and consolidation in infants with more disrupted night sleep, which may have implications for cognitive development.

Emerging Self-Representation Presents a Challenge When Perspectives Conflict

The capacity to take another's perspective appears to be present from early in life, with young infants ostensibly able to predict others' behaviour even when the self and other perspective are at odds. Yet, infants' abilities are difficult to reconcile with the well-known problems that older children have with ignoring their own perspective. Here we show that it is the development of the self-perspective, at around 18 months, that creates a perspective conflict between self and other during a non-verbal perspective-tracking scenario. Using mirror self-recognition as a measure of self-awareness and pupil dilation to index conflict processing, our results show that mirror recognisers perceive greater conflict during action anticipation, specifically in a high inhibitory demand condition, in which conflict between self and other should be particularly salient.

Tracking what went where across toddlerhood: Feature-location bound object representations in 2- to 3-year-olds' working memory

Two experiments examined the development of the ability to encode, maintain, and update integrated representations of occluded objects' locations and featural identities in working memory across toddlerhood. Sixty-eight 28- to 40-month-old US toddlers (13 Asian or Pacific Islander, 6 Black, 48 White, 1 multiracial; 40 girls; tested between February 2015 and July 2017) tracked the locations of different color beads that were hidden simultaneously (Experiment 1) or sequentially (Experiment 2). Toddlers' ability to reliably store feature-location bound object representations in working memory varied as a function of age, memory load, and task demands. These results bridge a developmental gap between infancy and early childhood and provide new insights into sources of limitation and developmental change in children's early object representational capacities.

Mothers' and fathers' executive function both predict emergent executive function in toddlerhood

There are multivariate influences on the development of children's executive function throughout the lifespan and substantial individual differences can be seen as early as when children are 1 and 2 years of age. These individual differences are moderately stable throughout early childhood, but more research is needed to better understand their origins. To some degree, individual differences in executive function are correlated between mother and child, but no research to date has examined these associations prior to when children are preschool age, nor have any studies considered the role of fathers' and mothers' executive function in tandem. Here, we use a sample of 484 families (Mothers 89.2% white; Fathers 92.5% white) in three countries (UK, USA, Netherlands) to investigate the role of each parents' executive function on the development of children's (49.7% female) executive function from 14 (M = 14.42, SD = 0.57) to 24 (M = 24.47, SD = 0.78) months, as well as parenting practices that underlie these associations. Results of structural equation models suggest stability in some-but not all-components of executive function and growing unity between components as children age. We replicate extant findings such that mothers' executive function predicts children's executive function over and above stability and extend these findings to include associations between father and child skills. We find an additive role of fathers' EF, similar in magnitude to the role of mothers' EF. Finally, for both mothers and fathers we find that sensitivity and autonomy supportive practices mediate the relations between parents' and children's executive function.

Profiles of Caregiver-Reported Executive Function in Children with Down Syndrome

Children with Down syndrome (DS) are at risk for challenges with aspects of executive function (EF). The current study explores whether heterogeneity in EF profiles can be detected within a sample of children with DS. Participants were 69 children with DS, ages 3-10 years (M = 6.23, SD = 1.91). T-scores from a caregiver-report measure of executive function were modeled using latent profile analysis, and auxiliary analyses examined the association between demographic and biomedical factors and probability of profile membership. The two-profile solution was the best fit for the sample, with a profile that involved elevated scores in working memory only ("Working Memory Only" profile; 43% of sample) and a "Multi-Domain" profile that involved elevated scores in planning, inhibition, and working memory (57%). The presence of congenital heart defects was associated with a higher probability of assignment to the Multi-Domain profile. Findings from this study contribute to the characterization of heterogeneous outcomes associated with DS.

Effects of Maternal and Child Lifetime Traumatic Stress Exposures, Infant Temperament, and Caregiving Quality on Preschoolers' Executive Functioning

We examined effects of maternal and child lifetime traumatic stress exposures, infant temperament, and caregiving quality on parent ratings of preschoolers' executive functioning (EF). Maternal lifetime trauma was associated with preschoolers' EF problems; this association was mediated by greater child trauma exposure. Infant temperament was associated with EF abilities, particularly among females. Among males, infant extraversion/surgency mediated the association of maternal lifetime trauma with poorer child EF. Caregiving quality was negatively associated with maternal and child trauma exposures but did not predict child EF. Findings have implications for interventions to identify children at risk for poor EF and optimize outcomes.

Attention and social communication skills of very preterm infants after training attention control: Bayesian analyses of a feasibility study

Background

Very preterm (VP) infants (born 28 to <32 weeks of gestation) are at risk of cognitive delays and lower educational attainments. These risks are linked to anomalies in attention and information processing that emerge in the first years of life. Early interventions targeting attention functioning may equip VP infants with key building blocks for later attainments.

Methods

We tested the feasibility of a randomised trial where VP infants took part in a computerised cognitive procedure to train attention control. Ten healthy VP infants aged approximately 12 months (corrected age) and randomly allocated with 1:1 ratio to the training (interactive computerised presentations) or an active control procedure completed the study. Before and after the training programme, participating infants completed a battery of screen-based attention tests, naturalistic attention and communication tasks, and temperament assessments. In a previous study we analysed the data concerning feasibility (e.g. recruitment and retention). In the paper presented here we considered the infants’ performance and used Bayesian regression in order to provide credible treatment estimates considering the data collected.

Results

Estimates indicate moderate treatment effects in visual memory: compared to controls, trained infants displayed improvements equivalent to 0.59 SD units. Trained infants also improved in their abilities to attend to less salient stimuli presentations by 0.82 SD units, compared to controls. However, results did not indicate relevant gains in attention habituation or disengagement. We also reported moderate improvements in focused attention during naturalistic tasks, and in directing other people’s attention to shared objects.

Discussion

The results warrant further investigation concerning the effectiveness of training attention control in VP infants, extending this line of research beyond our small and homogeneous sample of healthy VP infants. This study also emphasises the utility of Bayesian approaches in estimating potentially relevant effects in small samples or exploratory studies. The scope for further research on early attention control training is discussed in light of studies indicating VP children’s susceptibility to positive environmental inputs.

Trial registration

Registration ID: NCT03896490. Retrospectively registered at Clinical Trials Protocol Registration and Results System (clinicaltrials.gov).

The effect of simultaneous exposure on the attention selection and integration of segments and lexical tones by Urdu-Cantonese bilingual speakers

In the perceptual learning of lexical tones, an automatic and robust attention-to-phonology system enables native tonal listeners to adapt to acoustically non-optimal speech, such as phonetic conflicts in daily communications. Previous tone research reveals that non-native listeners who do not linguistically employ lexical tones in their mother tongue may find it challenging to attend to the tonal dimension or integrate it with the segmental features. However, it is unknown whether the attentional interference initially caused by a maternal attentional system would continue influencing the non-optimal tone perception for simultaneous bilingual teenagers. From an endpoint in the age of language acquisition, we investigate whether the tone-specific attention mechanism developed by the Urdu-Cantonese simultaneous bilinguals is automatic enough to assist them in adapting to a phonetically-conflicting environment. Three groups of teenagers engaged in a four-condition ABX task: Urdu-Cantonese simultaneous bilinguals, Cantonese native listeners, and Urdu-speaking, late learners of Cantonese. The results showed that although the simultaneous bilinguals could phonologically process Cantonese tones in a Cantonese-like way under a conflict-free listening condition, they still failed in adapting to the phonetic conflicts, especially the segment-induced ones. It thus demonstrated that the simultaneous exposure and years of regular education in Hong Kong local schools still could not automatically guarantee simultaneous bilingual processing of Cantonese tones. In interpreting the findings, it hypothesized that, except for simultaneous exposure, the development of a tone-specific attention mechanism is also likely to be L1-inhibitory, tone experience-driven, and language-specific for simultaneous bilinguals.

Development of directed global inhibition, competitive inhibition and behavioural inhibition during the transition between infancy and toddlerhood

Inhibitory control (IC) is a core executive function integral to self-regulation and cognitive control, yet is itself multi-componential. Directed global inhibition entails stopping an action on demand. Competitive inhibition is engaged when an alternative response must also be produced. Related, but not an executive function, is temperamentally-driven wariness of novelty, known as behavioural inhibition. Understanding early development of these components has been hampered by a shortage of suitable measures. We combine established and novel measures to capture directed global inhibition (Toy Prohibition, Touchscreen Prohibition), competitive inhibition (A-not-B, Early Childhood Inhibitory Touchscreen Task; ECITT) and behavioural inhibition (Touchscreen Approach) in 113 10- and 16-month-olds (73 seen longitudinally). ECITT performance shows good 1-week test-retest reliability at 10-months (r = 0.30-0.60) but little stability to 16-months. Directed global inhibition performance shows developmental progression but little stability of individual differences from 10 to 16 months. Performance on measures targeting similar IC components shows greater coherence at 16-months (r = 0.23-0.59) compared with 10-months (r = 0.09-0.35). Probing of ECITT condition effects indicates toddlers are more able, compared with infants, to override immediate prepotencies; indicative of increasingly flexible control over behaviour. However, exerting IC over cumulative prepotencies appears just as challenging for toddlers as infants. Exploratory analyses show little evidence for cross-sectional or longitudinal associations between behavioural, directed global and competitive inhibition. In combination, these findings indicate that IC is not yet a stable, unidimensional construct during the transition between infancy and toddlerhood, and highlight the need for careful selection of multiple measures for those interested in capturing early variation in IC.

The neural correlates of inhibitory control in 10-month-old infants: A functional near-infrared spectroscopy study

Inhibitory control, a core executive function, emerges in infancy and develops rapidly across childhood. Methodological limitations have meant that studies investigating the neural correlates underlying inhibitory control in infancy are rare. Employing functional near-infrared spectroscopy alongside a novel touchscreen task that measures response inhibition, this study aimed to uncover the neural underpinnings of inhibitory control in 10-month-old infants (N = 135). We found that when inhibition was required, the right prefrontal and parietal cortices were more activated than when there was no inhibitory demand. This demonstrates that inhibitory control in infants as young as 10 months of age is supported by similar brain areas as in older children and adults. With this study we have lowered the age-boundary for localising the neural substrates of response inhibition to the first year of life.

Infant Effortful Control Mediates Relations Between Nondirective Parenting and Internalising-Related Child Behaviours in an Autism-Enriched Infant Cohort

Internalising problems are common within Autism Spectrum Disorder (ASD); early intervention to support those with emerging signs may be warranted. One promising signal lies in how individual differences in temperament are shaped by parenting. Our longitudinal study of infants with and without an older sibling with ASD investigated how parenting associates with infant behavioural inhibition (8-14 months) and later effortful control (24 months) in relation to 3-year internalising symptoms. Mediation analyses suggest nondirective parenting (8 months) was related to fewer internalising problems through an increase in effortful control. Parenting did not moderate the stable predictive relation of behavioural inhibition on later internalising. We discuss the potential for parenting to strengthen protective factors against internalising in infants from an ASD-enriched cohort.

Inhibitory control within the context of early life poverty and implications for outcomes

Early life poverty confers risk for unfavorable outcomes including lower academic achievement, behavioral difficulties, and neurodevelopmental disorders. Disruptions in inhibitory control (IC) have been posed as one mechanism to explain the relationship between early life poverty and deleterious outcomes. There is robust research to suggest that early life poverty is associated with development of poorer IC. Further, poorer IC in children is related to decreased academic achievement and social competence, and increased externalizing and internalizing behavior. There is some parent-report evidence to suggest that IC is a mediator of the relationship between poverty and externalizing behaviors, as well as some limited evidence to suggest that IC is a mediator between poverty and academic achievement. Future work should aim to determine whether early life poverty's relation to IC could be explained by verbal ability which is thought to be central to the development of effective IC. In addition, future neuroimaging work should utilize IC fMRI tasks to identify key neural mechanisms that might contribute to a relationship between early life poverty and IC.

Testing the Bilingual Cognitive Advantage in Toddlers Using the Early Executive Functions Questionnaire

The present study aims to assess differences in executive functioning between monolingual and multilingual 23-month-old toddlers, both when dichotomizing multilingualism and assessing it on a continuum. It is hypothesized that multilinguals, individuals with greater non-dominant language exposure, and individuals with more translation equivalents, would perform better in the following domains: response inhibition, attentional flexibility, and regulation. No differences are expected for working memory. The Early Executive Functions Questionnaire, a newly developed parental report, is used to measure the four executive functions of interest. Multilinguals and individuals with greater non-dominant language exposure have significantly higher response inhibition; however, no differences are noted for any other executive function. Additionally, no associations between translation equivalents and executive functioning are found. Post-hoc analyses reveal that non-dominant language production had a positive correlation with working memory. The present findings support the notion of a domain-specific cognitive advantage for multilingual toddlers.

Inhibitory control and problem solving in early childhood: Exploring the burdens and benefits of high self-control

Low inhibitory control (IC) is sometimes associated with enhanced problem-solving amongst adults, yet for young children high IC is primarily framed as inherently better than low IC. Here, we explore associations between IC and performance on a novel problem-solving task, amongst 102 English 2- and 3-year-olds (Study 1) and 84 Swedish children, seen at 18-months and 4-years (Study 2). Generativity during problem-solving was negatively associated with IC, as measured by prohibition-compliance (Study 1, both ages, Study 2 longitudinally from 18-months). High parent-reported IC was associated with poorer overall problem-solving success, and greater perseveration (Study 1, 3-year-olds only). Benefits of high parent-reported IC on persistence could be accounted for by developmental level. No concurrent association was observed between problem-solving performance and IC as measured with a Delay-of-Gratification task (Study 2, concurrent associations at 4-years). We suggest that, for young children, high IC may confer burden on insight- and analytic-aspects of problem-solving.