Early executive function differences in infants born moderate-to-late preterm

The modulating effect of gestational age on attentional disengagement in toddlers

Gestational Age (GA) at birth plays a crucial role in identifying potential vulnerabilities to long-term difficulties in cognitive and behavioral development. The present study aims to explore the influence of gestational age on the efficiency of early visual attention orienting, as a potential marker for the development of specific high-level socio-cognitive skills. We administered the Gap-Overlap task to measure the attentional orienting and disengagement performance of 16-month-olds born between the 34th and 41st weeks of gestation. Our findings indicate that GA might be a significant predictor of attentional disengagement performance, with lower GAs associated with slower orienting of visual attention in the gap condition. Additionally, we discuss a possible influence of endogenous attention control on disengagement accuracy at this age, particularly among full-term infants. Overall, the findings highlight the role of GA as a key factor in evaluating early visual attention development, acting as a marker for detecting early vulnerabilities.

The newborn individualised developmental care and assessment program: A model of care for infants and families in hospital settings

AIM

The Newborn Individualised Developmental Care and Assessment Program (NIDCAP) is an intervention and education programme that uses developmental observation for multidisciplinary healthcare professionals (HCP) caring for high-risk infants and families. Infants prosper with the ongoing co-regulation process of infant and family that is influenced by the physical and social environment.

METHODS

The Template for Intervention Description and Replication (TIDieR) Guidelines were applied to the NIDCAP intervention. The estimation of the individual infant's current goals is described from direct observation of behaviour in the context of ongoing care delivery. The infant's behaviour guides all caregivers to articulate current strengths and functioning for the development of individualised plans of care and support. The NIDCAP Nursery Program supports the full integration of NIDCAP into the healthcare system.

RESULTS

NIDCAP is a system-based, process-oriented, attuned and responsive intervention for individualised developmental care for infants and families. Evidence shows NIDCAP significantly improves medical outcomes, with less time on the ventilator, improved weight gain, decreased length of stay, improved developmental outcomes and enhanced infant and family relationships. Evidence suggests that NIDCAP as an intervention improves parental competence, decreases stress for HCP teams and improves HCP satisfaction.

CONCLUSION

NIDCAP improves outcomes for infants and families requiring hospital care.

Release of Oxytocin and Cortisol Is Associated With Neurobehavioral Patterns in Premature Infants

OBJECTIVE

To examine relationships among salivary oxytocin and cortisol levels in parents and preterm infants and neurobehavioral functioning in preterm infants after skin-to-skin contact.

DESIGN

A secondary analysis of a randomized crossover study.

SETTING

NICU.

PARTICIPANTS

Twenty-eight stable premature infants and their mothers and fathers.

METHODS

Participating infants contributed 108 saliva samples that we collected 45 minutes after skin-to-skin contact and tested for oxytocin and cortisol. We randomized data collection by whether the infant was held first by the mother or by the father. We conducted linear regression to test if summary scores on the NICU Network Neurobehavioral Scale were associated with salivary oxytocin and cortisol levels.

RESULTS

We found a significant negative relationship between infant oxytocin levels and the Stress scores (b = -0.07, p < .01) and the Excitability scores (b = -1.12, p = .04) among infants held skin-to-skin with their mothers. We found a significant positive relationship between infant oxytocin levels and the Self-Regulatory scores (b = 0.38, p = .05) among infants held skin-to-skin with their mothers. We found a significant positive relationship between infant cortisol level and the Stress scores (b = 0.05, p = .04), Excitability scores (b = 1.06, p = 0.05), and Asymmetrical Reflexes scores (b = 1.21, p = .03) among infants held skin-to-skin with their mothers. We only found a negative significant relationship between infant cortisol levels and the Stress scores (b = -0.03, p = .04) among infants held skin-to-skin with their fathers.

CONCLUSION

We found that oxytocin is an important biomarker that may improve infant neurobehavioral functioning. The data showed a difference in oxytocin responses after skin-to-skin contact with mothers compared to fathers.

Fucosylated Human Milk Oligosaccharides during the First 12 Postnatal Weeks Are Associated with Better Executive Functions in Toddlers

Human milk oligosaccharides (HMOs) are one of the most abundant solid components in a mother's milk. Animal studies have confirmed a link between early life exposure to HMOs and better cognitive outcomes in the offspring. Human studies on HMOs and associations with later child cognition are scarce. In this preregistered longitudinal study, we investigated whether human milk 2'-fucosyllactose, 3'-sialyllactose, 6'-sialyllactose, grouped fucosylated HMOs, and grouped sialylated HMOs, assessed during the first twelve postnatal weeks, are associated with better child executive functions at age three years. At infant age two, six, and twelve weeks, a sample of human milk was collected by mothers who were exclusively (n = 45) or partially breastfeeding (n = 18). HMO composition was analysed by use of porous graphitized carbon-ultra high-performance liquid chromatography-mass spectrometry. Executive functions were assessed at age three years with two executive function questionnaires independently filled in by mothers and their partners, and four behavioural tasks. Multiple regression analyses were performed in R. Results indicated that concentrations of 2'-fucosyllactose and grouped fucosylated HMOs were associated with better executive functions, while concentrations of grouped sialylated HMOs were associated with worse executive functions at age three years. Future studies on HMOs that sample frequently during the first months of life and experimental HMO administration studies in exclusively formula-fed infants can further reveal associations with child cognitive development and uncover potential causality and sensitive periods.

Preterm infant body composition, working memory, and temperament

Altered body composition in preterm infants is associated with risks to cognitive development, but the effect specific to prefrontal cortex (PFC) development is unknown. We were interested in the impact of fat mass (FM) and fat free mass (FFM) gains out to 4 months corrected gestational age (CGA) on PFC development, as indexed by working memory and temperament. This is a prospective observational pilot study recruiting 100 preterm (<33 weeks gestation), appropriate for gestational age, and very low birth weight infants, of which 49 infants met inclusion criteria. Body composition was measured using air displacement plethysmography at hospital discharge and 4 months CGA. Questionnaire based temperament assessments were completed at 12 and 24 months CGA and a working memory assessment was completed at 24 months CGA. Associations between developmental tests and body composition obtained at term and 4 months were analyzed. Increased FM at discharge was associated with increased fear and decreased soothability at 12 months. Increased FM at 4 months was associated with increased activity level, increased distress from limitations at 12 months and decreased attentional shifting, decreased frustration, and decreased inhibitory control at 24 months. Increased FFM at 4 months was associated with increased activity level at 12 months and increased impulsivity and decreased low intensity pleasure at 24 months. In this exploratory pilot study, increased FM out to 4 months and increased FFM after discharge are associated with negative markers of infant temperament. Infant temperament may be sensitive to body composition status at least to 4 months CGA.

Tactile sensory processing as a precursor of executive attention: Toward early detection of attention impairments and neurodevelopmental disorders

Recent studies in developmental neuroscience tend to show the existence of neural attention networks from birth. Their construction is based on the first sensory experiences that allow us to learn the patterns of the world surrounding us and preserve our limited attentional resources. Touch is the first sensory modality to develop, although it is still little studied in developmental psychology in contrast to distal modalities such as audition or vision. Atypical tactile sensory processing at an early age could predict later attention dysfunction, both of them being part of the symptomatology of neurodevelopmental disorders (NDD). We review the state of knowledge on tactile sensory processing and its links with attention, executive attention (EA) in particular, and propose that abnormal tactile sensory processing at an early age could provide markers of EA dysfunctions, contributing to the early detection of NDD. This article is categorized under: Psychology > Attention.

Peripapillary Retinal Nerve Fiber Layer Thickness in Adults Born Extremely, Very, and Moderately Preterm With and Without Retinopathy of Prematurity: Results From the Gutenberg Prematurity Eye Study (GPES)

PURPOSE

This study investigated whether prematurity and associated factors or prenatal growth restriction have long-term effects on the peripapillary retinal nerve fiber layer (pRNFL) in adulthood.

DESIGN

Retrospective cohort study.

METHODS

The Gutenberg Prematurity Eye Study (GPES) is a retrospective cohort study with a prospective ophthalmologic examination in Germany. Selected individuals born term and preterm (age 18-52 years) were examined with spectral-domain optical coherence tomography (SD-OCT) in adulthood, and perinatal medical charts were reviewed. The pRNFL thickness was measured using SD-OCT. Univariate and multivariable linear regression analyses were conducted to investigate associations between pRNFL and gestational age (GA; categorical), birth weight percentile (categorical), retinopathy of prematurity (ROP) occurrence, and treatment and other perinatal parameters with adjustment for age, sex, and spherical equivalent.

RESULTS

In total, 766 eyes of 406 preterm and full-term individuals were included (mean age 28.4 ± 8.6 years, 228 females). After adjustment for age, sex, and spherical equivalent, global pRNFL thinning was associated with moderate (GA = 33-36 wk, β = -4.68, P < .001), very (GA = 29-32 wk, β = -5.72, P < .001), and extreme (GA ≤ 28 wk, β = -8.69, P < .001) prematurity but not with low birth weight percentile (<25th percentile, P = .9) and ROP occurrence (P = .9) in multivariable analysis. ROP treatment was associated with increased pRNFL in the temporal sector (P = .002). Maternal smoking during pregnancy showed an association with pRNFL thinning (P = .07).

CONCLUSION

Our data indicate that the more preterm individuals are born the more pRNFL thinning occurs, whereas prenatal growth restriction and postnatal occurrence of ROP show less effects on pRNFL thickness. Furthermore, individuals with severe ROP with treatment but not lower ROP stages without treatment showed an increased temporal pRNFL thickness.

Cognitive flexibility in 12-month-old preterm and term infants is associated with neurobehavioural development in 18-month-olds

There is growing evidence that preterm children are at an increased risk of poor executive functioning, which underlies behavioural and attention problems. Previous studies have suggested that early cognitive flexibility is a possible predictor of later executive function; however, how it develops in infancy and relates to the later neurobehavioural outcomes is still unclear in the preterm population. Here, we conducted a longitudinal study to investigate oculomotor response shifting in 27 preterm and 25 term infants at 12 months and its relationship with general cognitive development and effortful control, which is a temperamental aspect closely associated with executive function, at 18 months. We found that moderate to late preterm and term infants significantly inhibited previously rewarded look responses, while very preterm infants did not show significant inhibition of perseverative looking at 12 months. Moreover, lower inhibition of perseverative looking was significantly associated with lower general cognitive development and attentional shifting at 18 months. These findings suggest that the early atypical patterns of oculomotor response shifting may be a behavioural marker for predicting a higher risk of negative neurobehavioural outcomes, including attention-related problems in preterm children.

Early Detection of Cognitive, Language, and Motor Delays for Low-Income Preterm Infants: A Brazilian Cohort Longitudinal Study on Infant Neurodevelopment and Maternal Practice

Aim: This study examined the neurodevelopment trajectories, the prevalence of delays, and the risks and protective factors (adverse outcomes, environment, and maternal factors) associated with cognitive, motor, and language development for preterm infants from 4– to 24-months.

Method: We assessed 186 preterm infants (24.7% extremely preterm; 54.8% very preterm; 20.4% moderate/late preterm) from 4– to 24-months using the Bayley Scales of Infant Development – III. Maternal practices and knowledge were assessed using the Daily Activities of Infant Scale and the Knowledge of Infant Development Inventory. Birth risks and adverse outcomes were obtained from infant medical profiles.

Results: A high prevalence of delays was found; red flags for delays at 24-months were detected at 4– and 8-months of age. The neurodevelopmental trajectories showed steady scores across time for cognitive composite scores for extremely- and very-preterm infants and for language composite scores for the extremely- and moderate/late-preterm; a similar trend was observed for the motor trajectories of moderate/late preterm. Changes over time were restricted to motor composite scores for extremely- and very-preterm infants and for cognitive composite scores for moderate/late preterm; declines, stabilization, and improvements were observed longitudinally. Positive, strong, and significant correlations were for the neurodevelopment scores at the first year of life and later neurodevelopment at 18 and 24 months. The cognitive, language, and motor composite scores of extremely and very preterm groups were associated with more risk factors (adverse outcomes, environment, and maternal factors). However, for moderate/late preterm infants, only APGAR and maternal practices significantly explained the variance in neurodevelopment.

Discussion: Although adverse outcomes were strongly associated with infant neurodevelopment, the environment and the parents’ engagement in play and breastfeeding were protective factors for most preterm infants. Intervention strategies for preterm infants should start at 4– to 8-months of age to prevent unwanted outcomes later in life.

Two-year outcomes after dextrose gel prophylaxis for neonatal hypoglycaemia

OBJECTIVE

To determine the effect of prophylactic dextrose gel for prevention of neonatal hypoglycaemia on neurodevelopment and executive function at 2 years' corrected age.

DESIGN

Prospective follow-up of a randomised trial.

SETTING

New Zealand.

PATIENTS

Participants from the pre-hypoglycaemia Prevention with Oral Dextrose (pre-hPOD) trial randomised to one of four dose regimes of buccal 40% dextrose gel or equivolume placebo.

MAIN OUTCOME MEASURES

Coprimary outcomes were neurosensory impairment and executive function. Secondary outcomes were components of the primary outcomes, neurology, anthropometry and health measures.

RESULTS

We assessed 360 of 401 eligible children (90%) at 2 years' corrected age. There were no differences between dextrose gel dose groups, single or multiple dose groups, or any dextrose and any placebo groups in the risk of neurosensory impairment or low executive function (any dextrose vs any placebo neurosensory impairment: relative risk (RR) 0.77, 95% CI 0.50 to 1.19, p=0.23; low executive function: RR 0.50, 95% CI 0.24 to 1.06, p=0.07). There were also no differences between groups in any secondary outcomes. There was no difference between children who did or did not develop neonatal hypoglycaemia in the risk of neurosensory impairment (RR 1.05, 95% CI 0.68 to 1.64, p=0.81) or low executive function (RR 0.73, 95% CI 0.34 to 1.59, p=0.43).

CONCLUSION

Prophylactic dextrose gel did not alter neurodevelopment or executive function and had no adverse effects to 2 years' corrected age, but this study was underpowered to detect potentially clinically important effects on neurosensory outcomes.

Preterm Birth and the Development of Visual Attention During the First 2 Years of Life: A Systematic Review and Meta-analysis

Importance

Preterm birth is associated with an increased risk for long-lasting attention deficits. Early-life markers of attention abnormalities have not been established to date but could provide insights into the pathogenesis of attention abnormalities and could help identify susceptible individuals.

Objective

To examine whether preterm birth is associated with visual attention impairments in early life, and if so, in which attention functions and at which developmental period during the first 2 years of life.

Data Sources

PubMed and PsycINFO were searched on November 17, 2019, to identify studies involving visual attention outcomes in infants born preterm vs full term.

Study Selection

Peer-reviewed studies from the past 50 years met the eligibility criteria if they directly assessed visual attention outcomes until the age of 2 years in generally healthy infants born preterm or full term. The selection process was conducted by 2 independent reviewers.

Data Extraction and Synthesis

The Meta-analysis of Observational Studies in Epidemiology (MOOSE) reporting guideline was followed. Random-effects models were used to determine standardized mean differences. The risk of bias was assessed both within and between studies.

Main Outcomes and Measures

Five nascent indices of visual attention were analyzed, including very basic functions-namely, the abilities to follow and fixate on visual targets-and more complex functions, such as visual processing (ie, habituation), recognition memory (ie, novelty preference), and the ability to effortfully focus attention for learning.

Results

A total of 53 studies were included, with 69 effect sizes and assessing a total of 3998 infants (2047 born preterm and 1951 born full term; of the 3376 for whom sex was reported, 1693 [50.1%] were girls). Preterm birth was associated with impairments in various attention indices, including visual-following in infancy (Cohen d, -0.77; 95% CI, -1.23 to -0.31), latency to fixate (Cohen d, -0.18; 95% CI, -0.33 to -0.02), novelty preference (Cohen d, -0.20; 95% CI, -0.32 to -0.08), and focused attention (Cohen d, -0.28; 95% CI, -0.45 to -0.11). In the neonatal period, preterm birth was associated with superior visual-following (Cohen d, 0.22; 95% CI, 0.03 to 0.40), possibly owing to the additional extrauterine exposure to sensory stimulation. However, this early association waned rapidly in infancy (Cohen d, -0.77; 95% CI, -1.23 to -0.31).

Conclusions and Relevance

The findings suggest that preterm birth is associated with impingements to visual attention development in early life, as manifested in basic and then complex forms of attention. Advancements in neonatal care may underlie improvements found in the current era and accentuate several early protective factors.

Gestational Age is Dimensionally Associated with Structural Brain Network Abnormalities Across Development

Prematurity is associated with diverse developmental abnormalities, yet few studies relate cognitive and neurostructural deficits to a dimensional measure of prematurity. Leveraging a large sample of children, adolescents, and young adults (age 8-22 years) studied as part of the Philadelphia Neurodevelopmental Cohort, we examined how variation in gestational age impacted cognition and brain structure later in development. Participants included 72 preterm youth born before 37 weeks' gestation and 206 youth who were born at term (37 weeks or later). Using a previously-validated factor analysis, cognitive performance was assessed in three domains: (1) executive function and complex reasoning, (2) social cognition, and (3) episodic memory. All participants completed T1-weighted neuroimaging at 3 T to measure brain volume. Structural covariance networks were delineated using non-negative matrix factorization, an advanced multivariate analysis technique. Lower gestational age was associated with both deficits in executive function and reduced volume within 11 of 26 structural covariance networks, which included orbitofrontal, temporal, and parietal cortices as well as subcortical regions including the hippocampus. Notably, the relationship between lower gestational age and executive dysfunction was accounted for in part by structural network deficits. Together, these findings emphasize the durable impact of prematurity on cognition and brain structure, which persists across development.

Assessment of the executive functions of moderate preterm children in preschool age

This study assesses EF and socioemotional development in 30 MPT children between 4 and 6 years, comparing them with 31 FT children. Working Memory was assessed with Digit Span and Corsi Block, verbal inhibitory control and cognitive flexibility with The Shape School Test, visuomotor inhibition with Go/No-Go and socioemotional development with SDQ for parents. In our study, MPT preschoolers had a poorer working memory, inhibitory control and verbal cognitive flexibility, and more emotional problems compared. Our results suggest that there is no safe gestational age in prematurity, for this reason, EF of preterm children should be evaluated at an early age, so early intervention plans can be implemented, preventing preterm from entering primary education in disadvantage.

Exposure to in utero inflammation increases locomotor activity, alters cognitive performance and drives vulnerability to cognitive performance deficits after acute immune activation

Fetal exposure to intrauterine inflammation (IUI) affects brain development. Using intrauterine lipopolysaccharide (LPS) administration to induce a localized, rather than a systemic, inflammation, we have previously shown that IUI increases cytokine expression and microglia number, and reduces white matter in the brains of exposed offspring. Clinical data suggest that IUI may increase the risk for cognitive and neurodevelopmental disorders, however, IUI is often found in the context of preterm birth, making it difficult to disentangle the adverse effects of inflammation from those related to prematurity. Therefore, using a mouse model of IUI that does not involve preterm birth, operant tasks were used to evaluate motivation, attention, impulsivity, and locomotion. IUI-exposed offspring were found to have increased locomotion and increased motivation (females only), and testing in the 5-choice serial reaction time task (5-CSRTT) showed that IUI-exposed offspring performed more trials and could respond accurately at a shorter stimulus length. We have previously shown that IUI animals have a potentiated cytokine response to a "second hit" (acute LPS injection) in adulthood, so animals' performance in the 5CSRTT was evaluated following an acute injection of LPS. As opposed to the improved performance observed under baseline conditions, IUI exposed animals demonstrated a greater decrease in performance after an acute LPS administration. To identify putative molecular mechanisms underlying this potentiated decline in cognitive performance, PFC samples were collected immediately after post-LPS cognitive testing and targeted gene expression analysis was correlated with specific measures of cognitive performance. Three receptors important for neuron-microglia crosstalk were found to correlate with task performance in the males following acute LPS administration. These data demonstrate that early life exposure to localized inflammation of the uterus, in the absence of prematurity, increases locomotor activity and improves some aspects of cognitive performance, but drives a vulnerability for adult cognitive performance deficits in response to acute infection.

Rapid Infant Prefrontal Cortex Development and Sensitivity to Early Environmental Experience

Over the last fifteen years, the emerging field of developmental cognitive neuroscience has described the relatively late development of prefrontal cortex in children and the relation between gradual structural changes and children's protracted development of prefrontal-dependent skills. Widespread recognition by the broader scientific community of the extended development of prefrontal cortex has led to the overwhelming perception of prefrontal cortex as a "late developing" region of the brain. However, despite its supposedly protracted development, multiple lines of research have converged to suggest that prefrontal cortex development may be particularly susceptible to individual differences in children's early environments. Recent studies demonstrate that the impacts of early adverse environments on prefrontal cortex are present very early in development: within the first year of life. This review provides a comprehensive overview of new neuroimaging evidence demonstrating that prefrontal cortex should be characterized as a "rapidly developing" region of the brain, discusses the converging impacts of early adversity on prefrontal circuits, and presents potential mechanisms via which adverse environments shape both concurrent and long-term measures of prefrontal cortex development. Given that environmentally-induced disparities are present in prefrontal cortex development within the first year of life, translational work in intervention and/or prevention science should focus on intervening early in development to take advantages of this early period of rapid prefrontal development and heightened plasticity.

Association between small for gestational age and low birth weight with attention deficit and impaired executive functions in 3-6 years old children

BACKGROUND

Behavioral disorders and attention deficit hyperactivity disorder (ADHD) symptoms are frequently reported among children with history of small body size at birth and disproportionate intrauterine growth retardation. The current study aimed to investigate some factors like executive functions and attention deficit in children with history of Small for gestational age (SGA) and/or Low Birth Weight (LBW) at birth.

METHODS

A historical cohort study was done and 3-6 years old preschool children (with past history of SGA/LBW) from some kindergartens and health centers were selected. Control group was randomly selected among children with history of normal birth weight and appropriate for gestational age at birth. All children were interviewed by an expert psychologist. Variables related to their attention, development, and executive functions were assessed by ASQ, Conner's, and Wisconsin Card Sorting Test. Completed questionnaires related Attention deficit and indexes of executive functions were evaluated between children in case groups and their counterparts in controls.

RESULTS

Based on inclusion criteria, 229 preschool children entered the study. With regard to size for gestational age, 124 cases were categorized in the SGA/LBW group and the rest were assigned in the appropriate for gestational age (AGA) group. In the case group, NPE and Percent Perseverative Errors (PPE) scores were significantly lower than normal birth weight group (p = .0001, p = .015). Scores related B item of Conner's was significantly different between cases and their controls (p = .039, p = .035).

CONCLUSIONS

Our results indicated that children with past history of some risks at birth may suffer from complications related attention and executive functions in their childhood. Recommendations for further research are strongly suggested.