Development and validation of the Early Executive Functions Questionnaire: A carer‐administered measure of Executive Functions suitable for 9‐ to 30‐month‐olds

Executive functions (EFs) enable us to control our attention and behavior in order to set and work toward goals. Strong EF skills are linked to better academic performance, and greater health, wealth, and happiness in later life. Research into EF development has been hampered by a lack of scalable measures suitable for infancy through to toddlerhood. The 31-item Early Executive Functions Questionnaire (EEFQ) complements temperament measures by targeting cognitive and regulatory capabilities. Exploratory Factor Analysis (n = 486 8- to 30-month-olds) and Confirmatory Factor Analysis (n = 317 9- to 30-month-olds) indicate Inhibitory Control, Flexibility, and Working Memory items load onto a common “Cognitive Executive Function (CEF)” factor, while Regulation items do not. The CEF factor shows strong factorial measurement invariance for sex, and partial strong factorial measurement invariance for age. CEF and Regulation scores show limited floor and ceiling effects, good internal consistency, short-term stability, and convergent validity with carer-report measures of attentional control. The EEFQ is sensitive to developmental change. Results indicate that the widely overlooked period between late infancy and early toddlerhood may be a sensitive period for EF development. The low-resource demands of the EEFQ afford the possibility to study emergent EFs at scale; opening up new opportunities in basic developmental and intervention research

Impact of maternal depressive symptoms on the development of infant temperament: Cascading effects during the first year of life

Maternal depression is associated with a range of child development outcomes, including difficult temperament. This longitudinal study investigated whether depressive symptoms (DS) that mothers experience after childbirth predict infant negative affect (NA), as well as potential effects of infant NA on maternal DS, across the first year of life. In the study (N = 63), questionnaires (the Beck Depression Inventory Second Edition, and the Infant Behavior Questionnaire–Revised Very Short Form) were administered at 2 weeks, 4, 6, and 9 months after birth. Using path analysis, we tested five different models that could explain the relationship between maternal DS and infant NA. The best‐fitting model showed that the days immediately following childbirth represent an important time for the development of infant temperament as maternal mood significantly predicts infant NA for at least 4 months after birth. This does not constitute a single sensitive period; a new predictive effect emerges around 4 months of age, suggesting cascading influences of maternal DS across the first 6 months of life. These results suggest a need for support, should a mother experience DS, not only immediately after birth, but also throughout the early stages of parenting

Dynamic modulation of frontal theta power predicts cognitive ability in infancy

Cognitive ability is a key factor that contributes to individual differences in life trajectories. Identifying early neural indicators of later cognitive ability may enable us to better elucidate the mechanisms that shape individual differences, eventually aiding identification of infants with an elevated likelihood of less optimal outcomes. A previous study associated a measure of neural activity (theta EEG) recorded at 12-months with non-verbal cognitive ability at ages two, three and seven in individuals with older siblings with autism (Jones et al., 2020). In a pre-registered study (https://osf.io/v5xrw/), we replicate and extend this finding in a younger, low-risk infant sample. EEG was recorded during presentation of a non-social video to a cohort of 6-month-old infants and behavioural data was collected at 6- and 9-months-old. Initial analyses replicated the finding that frontal theta power increases over the course of video viewing, extending this to 6-month-olds. Further, individual differences in the magnitude of this change significantly predicted non-verbal cognitive ability measured at 9-months, but not early executive function. Theta change at 6-months-old may therefore be an early indicator of later cognitive ability. This could have important implications for identification of, and interventions for, children at risk of poor cognitive outcomes

Associations between touchscreen exposure and hot and cool inhibitory control in 10-month-old infants

Touchscreen use amongst young children has proliferated in recent years, yet little is known about the association between daily touchscreen exposure and inhibitory control in the first year of life. Previous research has found a negative association between the amount of television viewing and inhibitory control in early childhood, but it is unclear whether negative associations with screen use extend to touchscreens. The current study presents an exploratory analysis of the cross-sectional associations between inhibitory control and the amount of touchscreen use amongst 10-month-olds (n = 128–156). Touchscreen exposure was assessed via parent-report. In order to include a range of “hot” and “cool” aspects of inhibitory control, these skills were assessed using lab-based response inhibition and prohibition tasks as well as parent-reported observations of infants’ inhibitory control abilities and broader regulatory behaviors. A “Cognitive Executive Function (EEFQ-CEF)” score (encompassing Inhibitory Control, Flexibility, and Working Memory items) was included as a secondary broader executive function construct to examine whether effects showed specificity to inhibitory control rather than executive functions more generally. Correlation analyses indicated no association between touchscreen exposure and the four indices of IC. However, a positive association was found for the amount of touchscreen exposure and EEFQ-CEF once accounting for sociodemographic variables. The implications of these findings and future directions are discussed

Maternal depressive symptoms and infant temperament in the first year of life predict child behavior at 36 months of age

In a longitudinal study, mothers (N = 50) self-reported on their depressive symptoms (DS) and their child’s behavior during the first year and at 36 months postpartum. Maternal DS during infancy were associated with child conduct problems (CP), suggesting a long-term association between maternal mental health and the development of child behavior. Infant temperament was also associated with child behavior so that negative affect predicted child CP, while infant surgency was associated with later hyperactivity-inattention. This study contributes to the literature by jointly assessing the role of maternal DS and infant temperament and showing that these are independent predictors of childhood behavior

Mother-infant interaction characteristics associate with infant falling reactivity and child peer problems at pre-school age

This longitudinal study investigated the associations between mother-infant interaction characteristics at 9 months of age, maternal mental health, infant temperament in the first year postpartum, and child behaviour at 3 years of age. The infants (N = 54, 22 females) mainly had White British ethnic backgrounds (85.7%). Results showed that i) mother-infant dyadic affective mutuality positively correlated with infant falling reactivity, suggesting that better infant regulatory skills are associated with the dyad’s ability to share and understand each other’s emotions; and ii) maternal respect for infant autonomy predicted fewer child peer problems at 3 years of age, suggesting that maternal respect for the validity of the infant’s individuality promotes better social and emotional development in early childhood

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

Strong genetic influences on the stability of autistic traits in childhood

Objective: Disorders on the autism spectrum, as well as autistic traits in the general population, have been found to be both highly stable across age and highly heritable at individual ages. However, little is known about the overlap in genetic and environmental influences on autistic traits across age and the contribution of such influences to trait stability itself. The present study investigated these questions in a general population sample of twins. Method: More than 6,000 twin pairs were rated on an established scale of autistic traits by their parents at 8, 9, and 12 years of age and by their teachers at 9 and 12 years of age. Data were analyzed using structural equation modeling. Results: The results indicated that, consistently across raters, not only were autistic traits stable, and moderately to highly heritable at individual ages, there was also a high degree of overlap in genetic influences across age. Furthermore, autistic trait stability could largely be accounted for by genetic factors, with the environment unique to each twin playing a minor role. The environment shared by twins had virtually no effect on the longitudinal stability in autistic traits. Conclusions: Autistic traits are highly stable across middle childhood and this stability is caused primarily by genetic factors

The early childhood inhibitory touchscreen task: A new measure of response inhibition in toddlerhood and across the lifespan

Research into the earliest development of inhibitory control is limited by a lack of suitable tasks. In particular, commonly used inhibitory control tasks frequently have too high language and working memory demands for children under 3 years of age. Furthermore, researchers currently tend to shift to a new set of inhibitory control tasks between infancy, toddlerhood, and early childhood, raising doubts about whether the same function is being measured. Tasks that are structurally equivalent across age could potentially help resolve this issue. In the current report, a new response inhibition task, the Early Childhood Inhibitory Touchscreen Task (ECITT), was developed. This task can be minimally modified to suit different ages, whilst remaining structurally equivalent. In the new task, participants have to overcome a tendency to respond to a frequently rewarded location on a touchscreen and instead make an alternative response. The ECITT was validated in three independent studies (with additional data, N = 166, reported in Supporting Information). In Study 1 (N = 81), cross-sectional data indicated that inhibitory performance on the task improved significantly between 24 and 30 months of age. In Study 2 (N = 38), longitudinal data indicated steady improvement in inhibitory control between 18, 21 and 24 months, with significant stability in individual performance differences between each consecutive age in terms of accuracy (but not in terms of reaction time). Finally, in Study 3 (N = 64), inhibitory performance on a faster-paced version of the same task showed a similar developmental course across the lifespan (4–84 years) to other response inhibition tasks and was significantly correlated with Stop-signal performance. The ECITT extends the assessment of response inhibition earlier than previous tasks–into early toddlerhood. Because the task is simple and structurally equivalent across age, future longitudinal studies should benefit from using the ECITT to investigate the development of inhibitory control in a consistent manner across the toddler years and beyond