A Community-Based Study of Sleep and Cognitive Development in Infants and Toddlers

Paths of cognitive and social-emotional delays before age three in rural China: Predictive power on skills at preschool age

Cognitive and social-emotional development in the first three years of life is associated with later skills. However, little is known about the paths of developmental delays in both cognitive and social-emotional skills before age 3 or to what extent these paths predict later developmental outcomes. The aim of this study is to examine the associations between the different paths of developmental delays in both cognitive and social-emotional skills of children before age 3 and the levels of development of the children when they are preschool age. Using a longitudinal data collected at three time points from 1245 children and their caregivers in rural China, we identified four different paths of developmental delays in cognitive and social-emotional before age 3 and examined how these paths are associated with different levels of developmental outcomes at preschool age. We used a non-parametric standardization approach and an ordinary least squares model to perform our analyses. Findings show that rates of developmental delays in either cognitive or social-emotional domain or both domains are high at all different time points, ranging from 20% to 55% for cognitive delays and 42% to 61% for social-emotional delays. Over half of children experienced deteriorating levels of either cognitive or social-emotional development before age 3. A large share of children was found to be persistently delayed in either domain. Only a small share of children raised their levels of development in either domain before age 3. In addition, we identified certain socioeconomic status of the family that are associated with never or deteriorating path of child developmental delays. More importantly, we revealed that different paths of developmental delays before age 3 have predictive power on different levels of developmental outcomes at preschool age. Our results suggest that actions are needed at the earliest times to improve child development when children are still infants or toddlers.

The Association Between Infant Sleep, Cognitive, and Psychomotor Development: A Systematic Review

STUDY OBJECTIVES

To synthesize findings of original articles examining the association between sleep-wake patterns of typically developing infants aged 0-to-18 months and cognitive and psychomotor development.

METHODS

A systematic search strategy was used to identify articles assessing the association between infant sleep (0-to-18 months) and cognitive/psychomotor development (Medline, PsycINFO, SCOPUS). Of 7,136 articles screened, 22 articles met inclusion criteria, and the results were subsequently synthesized. A quality assessment was conducted, and studies were categorized as "poor", "fair", or "good".

RESULTS

Out of 22 studies, two found exclusively significant associations between infant sleep and cognitive/psychomotor development, three found no significant associations and 17 found mixed results. Studies with exclusively significant results used a single sleep variable and single timepoint designs. Studies finding mixed results or no significant associations used multiple sleep, developmental variables, or multi-timepoint designs. Eight out of 10 studies and seven out of eight studies investigating nocturnal and total sleep duration, respectively, found no significant association with developmental outcomes. While 63% of studies were rated as having good methodological quality, all studies but one had estimated power of less than 0.80.

CONCLUSION

Findings of this review do not support conclusive associations between sleep-wake patterns in infancy and cognitive/psychomotor development. This conclusion contrasts with the literature in older populations, questioning if the association between sleep and development is of a different nature in infancy, potentially because of brain maturation. More studies including larger samples will be needed to clarify the presence or absence of such an association.

Neurocognitive Effects of Sleep Disruption in Children and Adolescents

A main childhood task is learning. In this task, the role of sleep is increasingly demonstrated. Although most literature examining this role focuses on preadolescence and middle adolescence, some studies apply napping designs in preschoolers. Studies overall conclude that without proper sleep a child's cognitive abilities suffer, but questions on how and to what extent linger. Observational studies show the hazards of potential confounders such as an individual's resilience to poor sleep as well as developmental risk factors (eg, disorders, stressors). A better understanding of cognitive sleep neuroscience may have a big impact on pediatric sleep research and clinical applications.

Sleep problems during early and late infancy: Diverse impacts on child development trajectories across multiple domains

OBJECTIVE

Child developmental rate holds predictive value for early-stage developmental trajectories, yet few studies explored how sleep problems during different infancy stages impact this rate. This study aims to investigate the correlation between sleep problems and child developmental trajectories.

METHODS

This study utilized a prospective national cohort of 5006 children in Taiwan. The developmental inventories covering motor, cognitive, language, and socioemotional domains were collected through questionnaire-based in-person home interviews conducted at 3, 12, 24, and 36 months. Sleep problems data, encompassing bedtime regularity, sleep duration, and sleep quality, were collected at 3 and 12 months. Child developmental rate was assessed by analyzing the slope of developmental ability estimates over a period of time.

RESULTS

Bedtime regularity and high-quality sleep at 3 and 12 months were found to be significantly associated with intercepts across all domains (estimate = -0.196∼0.233, p < 0.033). Children with high-quality sleep at 3 months showed enhanced developmental slopes in socioemotional domains (estimate = 0.032, p < 0.001). Atypical sleep duration at 3 and 12 months had differential detrimental association with child development in various domains (estimate = -0.108∼-0.016, p < 0.048).

CONCLUSION

The relationship between sleep problems and child development exhibited variability based on the timing of exposure to these issues. Early exposure to low-quality sleep was significantly related to developmental functions and socioemotional developmental rate, potentially leading to increased developmental disparities as children age. Inadequate sleep duration in late infancy and excessive sleep duration in early infancy were both negatively associated with child development trajectories. Policymakers can use these findings to design targeted sleep programs for optimal child development.

Childhood sleep: physical, cognitive, and behavioral consequences and implications

BACKGROUND

Sleep problems in children have been increasingly recognized as a major public health issue. Previous research has extensively studied and presented many risk factors and potential mechanisms for children's sleep problems. In this paper, we aimed to identify and summarize the consequences and implications of child sleep problems.

DATA SOURCES

A comprehensive search for relevant English language full-text, peer-reviewed publications was performed focusing on pediatric sleep studies from prenatal to childhood and adolescence in a variety of indexes in PubMed, SCOPUS, and Psych Info published in the past two decades. Both relevant data-based articles and systematic reviews are included.

RESULTS

Many adverse consequences are associated with child sleep deficiency and other sleep problems, including physical outcomes (e.g., obesity), neurocognitive outcomes (e.g., memory and attention, intelligence, academic performance), and emotional and behavioral outcomes (e.g., internalizing/externalizing behaviors, behavioral disorders). Current prevention and intervention approaches to address childhood sleep problems include nutrition, exercise, cognitive-behavioral therapy for insomnia, aromatherapy, acupressure, and mindfulness. These interventions may be particularly important in the context of coronavirus disease 2019. Specific research and policy strategies can target the risk factors of child sleep as well as the efficacy and accessibility of treatments.

CONCLUSIONS

Given the increasing prevalence of child sleep problems, which have been shown to affect children's physical and neurobehavioral wellbeing, understanding the multi-aspect consequences and intervention programs for childhood sleep is important to inform future research direction as well as a public health practice for sleep screening and intervention, thus improving sleep-related child development and health.

Early sleep duration trajectories and children's cognitive development: a prospective cohort study

We aimed to investigate the association between sleep duration trajectories and cognitive performance in preschool-aged Chinese children. We included 2131 children from the Ma'anshan birth cohort (MABC) study. Sleep duration trajectories from 6 to 48 months of age were determined using the group-based trajectory modeling (GBTM). Children's intellectual development was assessed using the Wechsler Preschool and Primary Scale of Intelligence. Compared to those with a medium total sleep duration trajectory, children with a short total sleep duration trajectory had poorer cognitive performance on the Visual Spatial Index (VSI) (β = -3.65; 95% CI = -6.77 to -0.53), which was associated with an increased risk of a low full-scale intelligence quotient (FSIQ) (OR = 1.60; 95% CI = 1.02 to 2.51). The short total sleep duration trajectory was associated with a low VSI compared with both the medium total sleep duration trajectory and the long total sleep duration trajectory. Compared to children with normal nighttime sleep duration and normal daytime sleep duration trajectories, children with short nighttime sleep and long daytime sleep duration trajectories, normal nighttime sleep and long daytime sleep duration trajectories, and short nighttime sleep and normal daytime sleep duration trajectories all had lower cognitive performance. The restricted cubic spline (RCS) also showed that children with and appropriate total sleep duration, an adequate nighttime sleep duration, and a moderate daytime sleep duration had higher FSIQ.

CONCLUSIONS

The results of this study emphasize that a medium total sleep duration, adequate sleep at nighttime, and appropriate sleep in the daytime appear to be more beneficial for children's cognitive development.

WHAT IS KNOWN

• Sleep duration in infancy is strongly associated with neurocognitive development.

WHAT IS NEW

• Medium and long total sleep duration trajectories are beneficial for children's cognitive performance compared to the short total sleep duration trajectory. • A medium total sleep duration, adequate sleep at nighttime and appropriate sleep in the daytime appear to be more beneficial for children's cognitive development.

Does the feeding method affect the quality of infant and maternal sleep? A systematic review

Breastfeeding brings many benefits to both mother and infant. Although, many women stop breastfeeding their infants too soon. The perceived association between breastfeeding and sleep may influence their decision to terminate breastfeeding. In our systematic review, we focused on mapping the relationship between infant feeding method and total sleep time (TST), number of nocturnal awakenings, awakenings after sleep onset (WASO) of mothers and infants and sleep quality of mothers. We searched four databases according to selected keywords and inclusion criteria - articles published in peer-reviewed journals between 2012 and 2022; English language; a sample consisting of mothers, infants, or both (without psychiatric and health problems); a comparison of the sleep quality of breastfed and formula-fed children or breastfeeding and formula-fed mothers. We read 260 full texts of selected articles. A total of 35 articles were included in this review. Due to significant heterogeneity, meta-analysis was not possible to accomplish. The results are processed according to narrative synthesis. Most studies agree that breastfed infants wake up more often at night. Total sleep time and time spent awake during the night (WASO) did not differ between breastfed and non-breastfed infants. We observed identical results in sleep variables among mothers. Additionally, there was no difference in maternal sleep quality. The synthesis revealed that the results may have differed due to using subjective, objective methods or the infant's age. It is important to remember that night waking is a more complex concept. Infants wake for many reasons, not just due to breastfeeding. The narrative synthesis indicated that the chosen study design, measurement method, the variables, and the infant's age could influence outcomes. In addition, other variables appeared that may affect the entire process. Therefore, we recommend that attention be paid to this in future studies.

What daily factors affect the sleep habits of Japanese toddlers?

STUDY OBJECTIVES

Good sleep, especially during early childhood, is important for development. In Japan, the mean nocturnal sleep duration of toddlers is < 10 hours, and even if toddlers slept for > 11 hours/day, as recommended by the National Sleep Foundation, some of them showed late bedtime and late wake-up time or took long naps. Therefore, we provisionally assumed the minimal sleep conditions for Japanese toddlers, named Nenne-criteria, such as bedtime before 10:00 pm, nocturnal sleep duration of ≥ 9 hours, and < 1 average time of awakening after sleep onset, and investigated the important factors for good sleep.

METHODS

We analyzed cross-sectional data from online surveys describing the sleep-related behaviors of 2,124 toddlers and their caregivers. We compared the daily schedules that affect sleep between the Nenne-criteria-meet group and the not-meet group.

RESULTS

The Nenne-criteria-meet group showed better daytime behaviors than the not-meet group. Structural equation modeling on daily schedules revealed that, to increase sleep pressure at the appropriate time, it is important to restrict media viewing, play outdoors in the morning, have an early nap ending time, avoid hyperarousal-inducing behaviors before bedtime, maintain daily schedules regularly, and decrease social jetlag.

CONCLUSIONS

The Nenne-criteria are useful for screening Japanese toddlers who require intervention for sleep hygiene. To improve toddlers' sleep, it is important not only to guide the ideal bedtime but also to provide tips for improving daily schedules and to avoid suboptimal sleep-related behaviors.

CITATION

Murata E, Yoshizaki A, Fujisawa TX, Tachibana M, Taniike M, Mohri I. What daily factors affect the sleep habits of Japanese toddlers? J Clin Sleep Med. 2023;19(6):1089-1101.

Effect of combined procedural pain interventions during neonatal intensive care on sleep, cognitive development, and internalizing behavior: a follow-up analysis of a randomized controlled trial

ABSTRACT

Repeated procedural pain can cause preterm infants to spend excessive time awake at the cost of sleep and can have a detrimental impact on later cognitive and behavioral development. What's more, poor sleep may be correlated with worse cognitive development and more internalizing behaviors in infants and toddlers. In a randomized controlled trial (RCT), we found that combined procedural pain interventions (sucrose, massage, music, nonnutritive sucking, and gentle human touch) during neonatal intensive care could improve preterm infants' early neurobehavioral development. Here, we followed up the participants who were enrolled in the RCT to evaluate the effect of combined pain interventions on later sleep, cognitive development, and internalizing behavior and to determine whether sleep may moderate the effect of combined pain interventions on the cognitive development and internalizing behavior. Total sleep time and night awakenings at 3, 6, and 12 months old; the cognitive development (adaptability, gross motor, fine motor, language, and personal-social domains) at 12 and 24 months old measured by the Chinese version of Gesell Development Scale; and the internalizing behavior at 24 months old measured by the Chinese version of Child Behavior Checklist were assessed. Our findings showed the potential benefits of combined pain interventions during neonatal intensive care for preterm infant's later sleep, motor and language development, and internalizing behavior, and the effect of combined pain interventions on motor development and internalizing behavior might be moderated by the mean total sleep duration and night awakenings at 3, 6, and 12 months old.

The Architecture of Early Childhood Sleep Over the First Two Years

INTRODUCTION

The architecture and function of sleep during infancy and early childhood has not been fully described in the scientific literature. The impact of early sleep disruption on cognitive and physical development is also under-studied. The aim of this review was to investigate early childhood sleep development over the first two years and its association with neurodevelopment.

METHODS

This review was conducted according to the 2009 PRISMA guidelines. Four databases (OVID Medline, Pubmed, CINAHL, and Web of Science) were searched according to predefined search terms.

RESULTS

Ninety-three studies with approximately 90,000 subjects from demographically diverse backgrounds were included in this review. Sleep is the predominant state at birth. There is an increase in NREM and a decrease in REM sleep during the first two years. Changes in sleep architecture occur in tandem with development. There are more studies exploring sleep and early infancy compared to mid and late infancy and early childhood.

DISCUSSION

Sleep is critical for memory, learning, and socio-emotional development. Future longitudinal studies in infants and young children should focus on sleep architecture at each month of life to establish the emergence of key characteristics, especially from 7-24 months of age, during periods of rapid neurodevelopmental progress.

Associations between sociodemographic and behavioural parameters and child development depending on age and sex: a cross-sectional analysis

OBJECTIVES

To explore environmental and individual factors that are associated with child development and to investigate whether the strength of these associations differs according to the age of the children.

DESIGN

Cross-sectional study.

SETTING

This study was part of the LIFE Child study, a large cohort study conducted in Leipzig, Germany.

PARTICIPANTS

778 children aged between 0.5 and 6 years (48.6% girls, mean age=2.67 years).

OUTCOME MEASURES

The outcomes were cognitive development, language development, body and hand motor skills, social-emotional development, and tracing skills, measured with a standardised development test. We analysed the associations between development and gestational age, socioeconomic status (SES), sex, behavioural difficulties, siblings, sleep duration, breastfeeding duration and overweight/obesity. We also tested for interactions between these variables and child age or sex.

RESULTS

Higher gestational age (b ranging between 0.12 and 0.26) and higher SES (b ranging between 0.08 and 0.21) were associated with better outcomes in almost all developmental domains (all p<0.019). Children with older siblings had improved body and hand motor skills compared with children without older siblings (both b=0.55, all p<0.029). Boys had poorer scores than girls in body and hand motor skills and tracing (b=-0.45, -0.68 and -1.5, all p<0.019). Children with behavioural difficulties had significantly poorer outcomes in most developmental domains. Some of the associations with SES and sex were stronger in older than in younger children. Associations between gestational age and motor development were weaker in older children. We did not find significant associations between child development and sleep duration, breastfeeding duration or overweight/obesity.

CONCLUSION

Some factors had a protective, others an adverse effect on development of children under 6 years of age. The effect of SES and sex increased, while the effect of gestational age decreased with age.

TRIAL REGISTRATION NUMBER

NCT02550236.

Sleep disturbances in infants and young children following an acquired brain injury

STUDY OBJECTIVES

Sleep disturbances impact over half of older children and teens with acquired brain injury (ABI) following critical care hospitalization but are underevaluated in infants and young children. Given the importance of sleep in brain development and healing after injury, we hypothesized sleep disturbances would be associated with worse neurodevelopmental outcomes in infants with ABI.

METHODS

We performed a retrospective cohort study of 68 children aged 2-32 months following critical care hospitalization for ABI. The Brief Infant Sleep Questionnaire assessed sleep disturbances. Bayley Scales of Infant and Toddler Development, third edition and Adaptive Behavior Assessment System, third edition assessed developmental and adaptive functioning outcomes, respectively. t tests compared sleep characteristics in infants with ABI to historical healthy controls. Spearman's correlation evaluated relationships among sleep and outcomes. Multiple linear regression investigated relationships controlling for demographic and ABI characteristics.

RESULTS

Compared to healthy controls, children with ABI had shorter nighttime sleep duration (P = .01), longer daytime sleep duration (P < .001), and longer duration of nighttime awakenings (P < .001). Duration of night awakenings negatively correlated with Bayley Cognitive scores (Spearman's correlation = -.40). Night awakenings negatively correlated with worse Adaptive Behavior Assessment System, third edition General Adaptive Composite scores (Spearman's correlation = -.42). When controlling for demographic and ABI characteristics, ≥ 3 awakenings was significantly associated with worse Adaptive Behavior Assessment System, third edition General Adaptive Composite (β = -11.3; 95% confidence interval = -19.2, -3.5).

CONCLUSIONS

Sleep disturbances are associated with poorer outcomes in infants and toddlers after ABI. Sleep is vital to recovery and a potentially modifiable target to improve outcomes.

CITATION

Klapp JM, Hall TA, Riley AR, Williams CN. Sleep disturbances in infants and young children following an acquired brain injury. J Clin Sleep Med. 2022;18(10):2387-2395.

Effect of Play2Sleep on mother-reported and father-reported infant sleep: a sequential explanatory mixed-methods study of a randomized controlled trial

STUDY OBJECTIVES

This study evaluated the effect on infant sleep of a novel intervention (Play2Sleep) that combined infant sleep information with self-modeled video feedback on parent-infant interactions.

METHODS

An explanatory sequential mixed-methods design consisting of a randomized controlled trial with 63 mother-father-infant triads randomized to Play2Sleep or comparison home visit interventions was used. We used repeated measures analysis of covariance to detect changes in infant night wakings, nocturnal wakefulness, and sleep durations and Wilcoxon signed rank test to evaluate changes in perception of infant sleep problems. Family interviews (n = 20) were used to explain the quantitative findings and analyzed qualitatively using thematic analysis.

RESULTS

Play2Sleep was effective in reducing maternal-reported infant wakefulness, F(1,55) = 5.33, P = .03, partial η2 = .09, and the number of paternal-reported naps, F(1,58) = 4.90, P = .03, partial η2 = .08. Parents in the Play2Sleep group reported significant improvements in problematic infant sleep that were not observed in the comparison group; however, Play2Sleep was not effective in reducing the number of parent-reported night wakings. Information overwhelm, learning infant cues, and working together with a subtheme of father involvement were key qualitative themes developed to explain the quantitative results. Unplanned exploratory analyses revealed a significant improvement in maternal depression symptoms in the Play2Sleep group.

CONCLUSIONS

This study suggests Play2Sleep could improve infant sleep by promoting parental awareness of infant cues and father involvement and improving maternal depression. Additional research is needed to determine the optimal number and timing of sessions.

CLINICAL TRIAL REGISTRATION

Registry: ClinicalTrials.gov; Name: Play2Sleep: Using Play to Improve Sleep; URL: https://clinicaltrials.gov/ct2/show/NCT02742155; Identifier: NCT02742155.

CITATION

Keys EM, Benzies KM, Kirk VG, Duffett-Leger L. Effect of Play2Sleep on mother-reported and father-reported infant sleep: a sequential explanatory mixed-methods study of a randomized controlled trial. J Clin Sleep Med. 2022;18(2):439-452.

Sleep problems and infant motor and cognitive development across the first two years of life: The Beijing Longitudinal Study

The present study examined bidirectional effects between sleep problems (nocturnal awakenings and insufficient nocturnal sleep) and infant development (gross motor, fine motor, and cognition) in a sample of 182 infants (89 girls) and their parents living in Beijing (China). Using 3 waves of longitudinal data (at 6 months, 1 year, and 2 years of age), this study (a) explored the differences in sleep patterns and developmental outcomes between infants in the current sample and infants from other cultures; and primarily examined (b) whether nocturnal awakenings and insufficient nocturnal sleep prospectively predicted infant development; (c) or whether infant development predicted sleep problems. Mothers reported their children's sleep problems, and infant development was assessed with Bayley III. Sleep patterns of Beijing infants were slightly different from those from Finland and Singapore, and most scores on Bayley III in this Beijing sample were higher than those in Danish, Dutch and Sri Lankan samples. Sleep problems and developmental measures were stable across the 3 times of assessments, but cross-lagged associations were limited in number and strength. High scores on the Bayley at 6 months predicted less nocturnal awakenings at 1 year of age. Insufficient nocturnal sleep at 1 year predicted poor fine motor development at 2 years. Thus, findings suggest some bidirectional associations between infant development and sleep problems and further highlight the need to understand these relations within specific cultural contexts.

From Alpha Diversity to Zzz: Interactions among sleep, the brain, and gut microbiota in the first year of life

Sleep disorders have been linked to alterations of gut microbiota composition in adult humans and animal models, but it is unclear how this link develops. With longitudinal assessments in 162 healthy infants, we present a so far unrecognized sleep-brain-gut interrelationship. First, we report a link between sleep habits and gut microbiota: daytime sleep is associated with bacterial diversity, and nighttime sleep fragmentation and variability link with bacterial maturity and enterotype. Second, we demonstrate a sleep-brain-gut link: bacterial diversity and enterotype are associated with sleep neurophysiology. Third, we show that the sleep-brain-gut link is relevant in development: sleep habits and bacterial markers predict behavioral-developmental outcomes. Our results demonstrate the dynamic interplay between sleep, gut microbiota, and the maturation of brain and behavior during infancy, which aligns with the lately emerging concept of a sleep-brain-gut axis. Importantly, sleep and gut microbiota represent promising health targets since both can be modified non-invasively. As many adult diseases root in early childhood, leveraging protective factors of adequate sleep and age-appropriate gut microbiota in infancy could constitute a health promoting factor across the entire human lifespan.

Concordance between subjective and objective measures of infant sleep varies by age and maternal mood: Implications for studies of sleep and cognitive development

Infant habitual sleep has been proposed as an important moderator of development in domains such as attention, memory or temperament. To test such hypotheses, we need to know how to accurately and consistently assess habitual sleep in infancy. Common assessment methods include easy to deploy but subjective parent-report measures (diary/sleep questionnaire); or more labour-intensive but objective motor movement measures (actigraphy). Understanding the degree to which these methods provide converging insights is important, but cross-method agreement has yet to be investigated longitudinally. Moreover, it is unclear whether concordance systematically varies with infant or maternal characteristics that could represent confounders in observational studies. This longitudinal study (up to 4 study visits/participant) investigated cross-method concordance on one objective (7-day actigraphy) and three commonly used subjective (7-day sleep diary, Brief Infant Sleep Questionnaire, Sleep & Settle Questionnaire) sleep measures in 76 typically developing infants (age: 4–14 months) and assessed the impact of maternal characteristics (stress, age, education) and infant characteristics (age) on cross-method concordance. In addition, associations between objective and subjective sleep measures and a measure of general developmental status (Ages & Stages Questionnaire) were investigated. A range of equivalence analyses (tests of equivalence, correlational analyses, Bland-Altman plots) showed mixed agreement between sleep measures. Most importantly, cross-method agreement was associated with maternal stress levels and infant age. Specifically, agreement between different measures of night waking was better for mothers experiencing higher stress levels and was higher for younger than older infants; the reverse pattern was true for day sleep duration. Interestingly, objective and subjective measures did not yield the same patterns of association with developmental domains, indicating that sleep method choice can influence which associations are found between sleep and cognitive development. However, results converged across day sleep and problem-solving skills, highlighting the importance of studying day sleep in future studies. We discuss implications of sleep method choice for investigating sleep in the context of studying infant development and behaviour.

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A range of equivalence analyses showed mixed agreement between subjective and objective sleep measures.

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Cross-method agreement was associated with maternal stress levels and infant age.

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Objective and subjective measures did not yield the same patterns of association with developmental domains except for day sleep duration.

Type of Milk Feeding and Introduction to Complementary Foods in Relation to Infant Sleep: A Systematic Review

Inconsistent conclusions from infant sleep and feeding studies may influence parents feeding-related decisions. This study aimed to systematically review the existing literature on infant sleep and its relation to the timing of introduction to complementary foods and type of milk feeding to better understand their role(s) in infant sleep. Cohort, longitudinal, cross-sectional studies, and controlled trials were identified using online searches of five databases up to April 2020. Twenty-one articles with a total of 6225 infants under 12 months-of-age were eligible. Exclusively breastfed infants (≤6 months-of-age) had a greater number of night wakings, but most studies (67%) reported no difference in night-time and 24 h sleep duration compared to formula-fed infants. However, after 6 months-of-age, most studies (>65%) reported breastfed infants to sleep less in the night-time and over 24 h compared to formula-fed infants. Furthermore, studies reported no association between the timing of introduction to complementary foods and infant sleep duration (<12 months-of-age). Future studies using standardized methodologies and definitions, transdisciplinary expertise, and longitudinal design are required to better understand the complex role of feeding on sleep.

The role of prior sleep for divergent thinking in infants

Higher-order cognitive functions seem particularly vulnerable to disruptions in prior sleep in school-aged children and adult populations. This study tested whether divergent thinking in infants varied as a function of prior sleep. Forty-three infants aged 13-16 months participated in a behavioural assessment of divergent thinking. Length of wakefulness since last sleep was experimentally manipulated. In addition, potential relations between divergent thinking and sleep quantity and quality during the night immediately before the assessment, as well as during three consecutive nights preceding the assessment, were examined using actigraphy recordings in combination with parent diaries. Divergent thinking was not impaired by lack of sleep within the previous 4 h. Divergent thinking was consistently related to night-time sleep quality and quantity prior to the assessment. These results suggest that timing of prior naturally occurring daytime sleep is less relevant for emergent divergent thinking capacity than quality and quantity of preceding night-time sleep.

Sleep Consolidation, Sleep Problems, and Co-Sleeping: Rethinking Normal Infant Sleep as Species-Typical

Infants evolved in the context of close contact (including co-sleeping). Evolutionary context is rarely considered in psychological infant sleep research, and Western sleep researchers make assumptions about what optimal "normal" infant sleep is and how to achieve early, deep, infant sleep consolidation and avoid infant sleep problems. However, an evolutionary and anthropological view of infant sleep as species-typical recognizes that human evolution likely prepared the infant brain for optimal development within its evolutionary context - co-sleeping. Thus, "normal" infant sleep, sleep consolidation, and sleep problems should all be understood within the framework of co-sleeping infants, not the historically new-phenomenon of solitary-sleeping infants. Much work needs to be done in order to understand "normal" infant sleep as species-typical and how adaptive infants are to environments that stray from their evolutionary norm.

Social-emotional, sleep and feeding problems in young patients with agenesis of the corpus callosum and the life quality of their parents

Agenesis of the corpus callosum (ACC) is a common congenital brain malformation. Most patients with no combined abnormalities have a good prognosis, but impairments have been observed in their sleep, feeding, and higher-order cognitive functions. Sixty-three Chinese ACC patients, aged 0-3 years, were included in our cross-sectional online research. The Chinese version of Infant-Toddler Social and Emotional Assessment (ITESA), the Brief Infant Sleep Questionnaire (BISQ), and the Montreal Children's Hospital Feeding Scale (MCH-FS) were used to assess these patients. We also used the brief version of the World Health Organization's Quality of Life Instrument (WHOQOL-BREF) to evaluate their parents. 43% of patients had ITESA domain problem: 10% in Externalizing, 7% in Internalizing, 3% in Dysregulation, and 30% in Competence. 52% of the patients were rated by their parents as having a sleep problem. Feeding difficulties occurred in 23% of patients. Patients' sleep and feeding problems were significantly correlated with their social and emotional performance, which influenced the life quality of their parents. Patients with intracranial abnormalities had more internalizing problems. In conclusion, sleep and feeding problems in young ACC patients might indicate their social-emotional problems. The problems in ACC patients were correlated with the life quality of their parents.

Neurocognitive Effects of Sleep Disruption in Children and Adolescents

A main childhood task is learning. In this task, the role of sleep is increasingly demonstrated. Although most literature examining this role focuses on preadolescence and middle adolescence, some studies apply napping designs in preschoolers. Studies overall conclude that without proper sleep a child's cognitive abilities suffer, but questions on how and to what extent linger. Observational studies show the hazards of potential confounders such as an individual's resilience to poor sleep as well as developmental risk factors (eg, disorders, stressors). A better understanding of cognitive sleep neuroscience may have a big impact on pediatric sleep research and clinical applications.

Digital Media Exposure and Predictors for Screen Time in 12-Month-Old Children: A Cross-Sectional Analysis of Data From a German Birth Cohort

Background: Early exposure to digital media may affect the physical and cognitive development in young children. The American Academy of Pediatrics and national guidelines recommend no digital media use at all under the age of 18 months. The aim of our study was to determine the actual exposure to digital media in 12-month-old infants and to reveal potential risk factors for screen time. Methods: In this prospective cross-sectional survey, data was collected from the KUNO Kids birth cohort study using parent-report questionnaires regarding the media exposure of the study child. We determined age at first contact with different digital media, mean screen time on an average weekday, and the influence of major demographic and socioeconomic factors. Results: Data for screen time analysis was available for 630 children. In summary, 45% of children had already been exposed to digital media by their first birthday. The most frequent first digital media exposure was the TV (33.0%) followed by smartphones (16.9%), both most commonly exposed to around the age of 8 months. On a regular weekday, 20% of the children spent 0.5-1 h in front of a TV and 9% were exposed to a smartphone for the same time frame, compared to 31% of joint parent-child media use. Predictors for screen time were having one sibling, less living space per person, and excessive TV use in the household, the latter of which doubled the chance of the child being exposed to digital media. Conclusion: A proportion of 10% of 1-year-old children were already regularly exposed to digital media. The TV remains the most predominant device but new media, particularly smartphones, might be catching up. Our study provides further support that family TV time is a major predictor of infant screen time. Pediatric recommendations should be re-evaluated in the light of the actual exposure to digital media already in infancy and parents should be proactively counseled regarding possible effects on child development.

Sleep and Early Brain Development

The early years of life are characterized by dramatic developmental changes. Within this important time period lies the transition from newborn to childhood. Sleep is one of the primary activities of the brain during early development and plays an important role in healthy cognitive and psychosocial development in early life. This paper will first review the normal sleep characteristics and their development in neonates and children, including architecture of sleep, development of a healthy sleep rhythm in early childhood, sleep recommendations and cultural disparity, as well as important factors for establishing a healthy sleep pattern during the first years of life, such as regular and consistent bedtime routine, safe and comfortable sleep environment, and appropriate sleep onset associations. This paper then provides recent updates of evidence of the effects of sleep on early brain development, particularly on learning and memory, emotional regulation, and general cognitive development through behavioral and neurophysiological studies. As regards the mechanism, many experimental sleep deprivation studies in animals and adults have attempted to explain the underlying mechanisms of sleep on cognition and the emotional brain. Future studies are expected to delineate the effects of sleep on brain structural and functional networks in the developing brain with the marked development of image acquisition approaches and the novel analysis tools for infants and young children in recent years.