Transactional models of parenting and infant sleep call attention to bidirectional associations among parenting, the biosocial environment, and infant sleep behaviors. Although night waking and bedtime fussing are normative during infancy and early childhood, they can be challenging for parents. The current study, conducted in the United States between 2003 and 2009, examined concurrent and longitudinal associations between maternal mental health and infant sleep during the first year. Concurrent associations at 6 and 12 months and longitudinal associations from 6 to 12 months were studied in a non-clinic referred sample of 171 economically and culturally diverse families. Mothers with poorer mental health reported that their infants had more night waking and bedtime distress and were more bothered by these sleep issues. Associations between infant sleep and maternal mental health were moderated by culture (Hispanic/Asian vs. other) and by stressors that included high parenting stress, more stressful life events, and low family income. Individual differences in maternal well-being may color mothers’ interpretations of infants’ sleep behaviors. It may be prudent to intervene to support maternal mental health when infants are referred for sleep problems.
night waking; infancy; sleep problems; depressive symptoms; anxiety; United States; mothers; ethnicity
Examine the prevalence, patterns, and persistence of parent-reported sleep problems during the first 3 years of life.
Three hundred fifty-nine mother/child pairs participated in a prospective birth cohort study. Sleep questionnaires were administered to mothers when children were 6, 12, 24, and 36 months old. Sleep variables included parent response to a nonspecific query about the presence/absence of a sleep problem and 8 specific sleep outcome domains: sleep onset latency, sleep maintenance, 24-hour sleep duration, daytime sleep/naps, sleep location, restlessness/vocalization, nightmares/night terrors, and snoring.
Prevalence of a parent-reported sleep problem was 10% at all assessment intervals. Night wakings and shorter sleep duration were associated with a parent-reported sleep problem during infancy and early toddlerhood (6–24 months), whereas nightmares and restless sleep emerged as associations with report of a sleep problem in later developmental periods (24–36 months). Prolonged sleep latency was associated with parent report of a sleep problem throughout the study period. In contrast, napping, sleep location, and snoring were not associated with parent-reported sleep problems. Twenty-one percent of children with sleep problems in infancy (compared with 6% of those without) had sleep problems in the third year of life.
Ten percent of children are reported to have a sleep problem at any given point during early childhood, and these problems persist in a significant minority of children throughout early development. Parent response to a single-item nonspecific sleep query may overlook relevant sleep behaviors and symptoms associated with clinical morbidity.
sleep problems; infants; toddlers; prevalence; persistence
The transition to parenthood can be stressful for new parents, as parents must learn to take on new roles and responsibilities. Sleep disruption—which has been linked in prior research to parent distress and fatigue—is common in the early months. The current study is the first to our knowledge to examine infant sleep and its potential indirect influence on parents’ perceptions of coparenting quality at 1 and 3 months of infant age. Participants included 150 families. Mothers reported more night waking, poorer sleep quality, more depressive symptoms, and worse perceptions of coparenting quality as compared with fathers. We tested a structural model of infant and parent night waking and sleep quality as predictors of parent distress and coparenting using maximum likelihood estimation. The frequency of infant night waking predicted father and mother night waking, which in turn predicted parent sleep quality. Poor parent sleep quality predicted elevated depressive symptoms, and finally depressive symptoms were negatively related to perceptions of coparenting quality. Significant indirect effects between infant night waking and parent depression and coparenting quality were found. In summary, both mothers’ and fathers’ perceptions of coparenting were related to the unfolding parental dynamics that take place surrounding infant sleep difficulties. This held true even after controlling for parent education, family income, and infant temperament. Therefore, parenting may indirectly benefit from interventions targeting infant sleep difficulties.
Transition to parenthood; coparenting; parent sleep; infant sleep; depression
Infant crying and sleep problems (e.g. frequent night waking, difficulties settling to sleep) each affect up to 30% of infants and often co-exist. They are costly to manage and associated with adverse outcomes including postnatal depression symptoms, early weaning from breast milk, and later child behaviour problems. Preventing such problems could improve these adverse outcomes and reduce costs to families and the health care system. Anticipatory guidance-i.e. providing parents with information about normal infant sleep and cry patterns, ways to encourage self-settling in infants, and ways to develop feeding and settling routines before the onset of problems-could prevent such problems. This paper outlines the protocol for our study which aims to test an anticipatory guidance approach.
750 families from four Local Government Areas in Melbourne, Australia have been randomised to receive the Baby Business program (intervention group) or usual care (control group) offered by health services. The Baby Business program provides parents with information about infant sleep and crying via a DVD and booklet (mailed soon after birth), telephone consultation (at infant age 6-8 weeks) and parent group session (at infant age 12 weeks). All English speaking parents of healthy newborn infants born at > 32 weeks gestation and referred by their maternal and child health nurse at their first post partum home visit (day 7-10 postpartum), are eligible. The primary outcome is parent report of infant night time sleep as a problem at four months of age and secondary outcomes include parent report of infant daytime sleep or crying as a problem, mean duration of infant sleep and crying/24 hours, parental depression symptoms, parent sleep quality and quantity and health service use. Data will be collected at two weeks (baseline), four months and six months of age. An economic evaluation using a cost-consequences approach will, from a societal perspective, compare costs and health outcomes between the intervention and control groups.
To our knowledge this is the first randomised controlled trial of a program which aims to prevent both infant sleeping and crying problems and associated postnatal depression symptoms. If effective, it could offer an important public health prevention approach to these common, distressing problems.
Trial registration number
Circadian phase and its relation to sleep are increasingly recognized as fundamental factors influencing human physiology and behavior. Dim light melatonin onset (DLMO) is a reliable marker of the timing of the circadian clock, which has been used in experimental, clinical, and descriptive studies in the past few decades. Although DLMO and its relationship to sleep have been well documented in school-aged children, adolescents, and adults, very little is known about these processes in early childhood. The purpose of this study was 1) to describe circadian phase and phase angles of entrainment in toddlers and 2) to examine associations between DLMO and actigraphic measures of children's nighttime sleep. Participants were 45 healthy toddlers aged 30 to 36 months (33.5 ± 2.2 months; 21 females). After sleeping on a parent-selected schedule for 5 days (assessed with actigraphy and diaries), children participated in an in-home DLMO assessment involving the collection of saliva samples every 30 minutes for 6 hours. Average bedtime was 2015 ± 0036 h, average sleep onset time was 2043 ± 0043 h, average midsleep time was 0143 ± 0038 h, and average wake time was 0644 ± 0042 h. Average DLMO was 1929 ± 0051 h, with a 3.5-hour range. DLMO was normally distributed; however, the distribution of the bedtime, sleep onset time, and midsleep phase angles of entrainment were skewed. On average, DLMO occurred 47.8 ± 47.6 minutes (median = 39.4 minutes) before bedtime, 74.6 ± 48.0 minutes (median = 65.4 minutes) before sleep onset time, 6.2 ± 0.7 hours (median = 6.1 hours) before midsleep time, and 11.3 ± 0.7 hours before wake time. Toddlers with later DLMOs had later bedtimes (r = 0.46), sleep onset times (r = 0.51), midsleep times (r = 0.66), and wake times (r = 0.65) (all p < 0.001). Interindividual differences in toddlers’ circadian phase are large and associated with their sleep timing. The early DLMOs of toddlers indicate a maturational delay in the circadian timing system between early childhood and adolescence. These findings are a first step in describing the fundamental properties of the circadian system in toddlers and have important implications for understanding the emergence of sleep problems and the consequences of circadian misalignment in early childhood.
circadian phase; melatonin; DLMO; sleep; phase angle of entrainment; early childhood; toddlers; children
Behavioral sleep problems are highly common in early childhood. These sleep problems have a high tendency to persist, and they may have deleterious effects on early brain development, attention, and mood regulation. Furthermore, secondary effects on parents and their relationship are documented. Negative parental cognition and behavior have been found to be important influencing factors of a child’s behavioral sleep problems. Therefore, in the current study we examined the acceptance and efficacy of a newly developed Internet-based intervention program called Mini-KiSS Online for sleep disturbances for children aged 6 months to 4 years and their parents.
Patients and methods
Fifty-five children (54.54% female; aged 8–57 months) suffering from psychophysiological insomnia or behavioral insomnia participated in the 6-week online treatment. Sleep problems and treatment acceptance were examined with a sleep diary, anamnestic questionnaires, a child behavior checklist (the Child Behavior Checklist 1.5–5), and treatment evaluation questionnaires.
The evaluation questionnaires showed a high acceptance of Mini-KiSS Online. Parents would recommend the treatment to other families, were glad to participate, and reported that they were able to deal with sleep-related problems of their child after Mini-KiSS Online. Parental behavior strategies changed with a reduction of dysfunctional strategies, such as staying or soothing the child until they fell asleep, allowing the child to get up again and play or watch TV, or reading them another bedtime story. Frequency and duration of night waking decreased as well as the need for external help to start or maintain sleep. All parameters changed significantly, not only in the questionnaires but also in the sleep diary.
Mini-KiSS Online is shown to be a highly accepted and effective treatment to change parental behavior and reduce behavioral sleep problems in early childhood.
insomnia; childhood; behavioral insomnia of childhood; online treatment; parental behavior
Objective. The purpose of this study was to determine whether the relationship between stressful infant environments and later childhood anxiety and depressive symptoms varies as a function of individual differences in temperament style.
Methods. Data was drawn from the Longitudinal Study of Australian Children (LSAC). This study examined 3425 infants assessed at three time points, at 1-year, at 2/3 years and at 4/5 years. Temperament was measured using a 12-item version of Toddler Temperament Scale (TTS) and was scored for reactive, avoidant, and impulsive dimensions. Logistic regression was used to model direct relationships and additive interactions between early life stress, temperament, and emotional symptoms at 4 years of age. Analyses were adjusted for socioeconomic status, parental education, and marital status.
Results. Stressful family environments experienced in the infant's first year of life (high versus low) and high reactive, avoidant, and impulsive temperament styles directly and independently predicted anxiety and depressive problems in children at 4 years of age. There was no evidence of interaction between temperament and family stress exposure.
Conclusions. Both infant temperament and stress exposures are independent and notable predictors of later anxiety and depressive problems in childhood. The risk relationship between stress exposure in infancy and childhood emotion problems did not vary as a function of infant temperament. Implications for preventive intervention and future research directions are discussed.
The relations of infant temperament and parents' marital satisfaction to mother and father involvement in early (T1, approximately 7 months, n = 142) and later (T2, approximately 14 months, n = 95) infancy were examined. At each assessment point, mothers and fathers completed daily diaries together to measure their involvement over four days (i.e., 2 weekdays and 2 weekend days), each partner reported on marital satisfaction, and mothers reported on infants' temperament. Structural equation models indicated that when infants were more temperamentally regulated, parents were more satisfied in their marital relationships. Parents' marital satisfaction mediated the association between more regulated infant temperament and greater mother involvement at T1 (but not at T2) and father involvement at T2 (but not at T1). The findings are discussed in terms of the implications of infant temperament and family relationships for parental involvement.
infant temperament; marital satisfaction; mother and father involvement
Secure parent-child relationships are implicated in children’s self-regulation, including the ability to self-soothe at bedtime. Sleep, in turn, may serve as a pathway linking attachment security with subsequent emotional and behavioral problems in children. We used path analysis to examine the direct relationship between attachment security and maternal-reports of sleep problems during toddlerhood, and the degree to which sleep serves as a pathway linking attachment with subsequent teacher-reported emotional and behavioral problems. We also examined infant negative emotionality as a vulnerability factor that may potentiate attachment-sleep-adjustment outcomes. Data were drawn from 776 mother-infant dyads participating in the NICHD Study of Early Child Care (SECC). In the full sample, after statistically adjusting for mother and child characteristics, including child sleep and emotional and behavioral problems at 24 months, we did not find evidence for a statistically significant direct path between attachment security and sleep problems at 36 months; however, there was a direct relationship between sleep problems at 36 months and internalizing problems at 54 months. Path models that examined the moderating influence of infant negative emotionality demonstrated significant direct relationships between attachment security and toddler sleep problems, and sleep problems and subsequent emotional and behavioral problems, but only among children characterized by high negative emotionality at 6 months of age. In addition, among this subset, there was a significant indirect path between attachment and internalizing problems through sleep problems. These longitudinal findings implicate sleep as one critical pathway linking attachment security with adjustment difficulties, particularly among temperamentally vulnerable children.
Sleep; attachment security; emotional and behavioral adjustment; toddler development; negative emotionality
Purpose of review
Sleep–wake problems such as night wakings, excessive crying, or difficulties in falling asleep are frequent behavioral issues during childhood. Maturational changes in sleep and circadian regulation likely contribute to the development and maintenance of such problems. This review highlights the recent research examining bioregulatory sleep mechanisms during development and provides a model for predicting sleep–wake behavior in young humans.
Findings demonstrate that circadian and sleep homeostatic processes exhibit maturational changes during the first two decades of life. The developing interaction of both processes may be a key determinant of sleep–wake and crying behavior in infancy. Evidence shows that the dynamics of sleep homeostatic processes slow down in the course of childhood (i.e., sleep pressure accumulates more slowly with increasing age) enabling children to be awake for consolidated periods during the day. Another current topic is the adolescent sleep phase delay, which appears to be driven primarily by maturational changes in sleep homeostatic and circadian processes.
The two-process model of sleep regulation is a valuable framework for understanding and predicting sleep–wake behavior in young humans. Such knowledge is important for improving anticipatory guidance, parental education, and patient care, as well as for developing appropriate social policies.
adolescence; children; excessive crying; sleep behavior; sleep homeostasis
Early social withdrawal and protective parenting predict a host of negative outcomes, warranting examination of their development. Mothers’ accurate anticipation of their toddlers’ fearfulness may facilitate transactional relations between toddler fearful temperament and protective parenting, leading to these outcomes. Currently, we followed 93 toddlers (42 female; on average 24.76 months) and their mothers (9% underrepresented racial/ethnic backgrounds) over 3 years. We gathered laboratory observation of fearful temperament, maternal protective behavior, and maternal accuracy during toddlerhood and a multi-method assessment of children’s social withdrawal and mothers’ self-reported protective behavior at kindergarten entry. When mothers displayed higher accuracy, toddler fearful temperament significantly related to concurrent maternal protective behavior and indirectly predicted kindergarten social withdrawal and maternal protective behavior. These results highlight the important role of maternal accuracy in linking fearful temperament and protective parenting, which predict further social withdrawal and protection, and point to toddlerhood for efforts of prevention of anxiety-spectrum outcomes.
Temperament; parenting; inhibition; social withdrawal
The current study examined associations among actigraphy, maternal sleep diaries, and the parent-completed child behavior checklist (CBCL) sleep items. These items are often used as a sleep measure despite their unclear validity with young children. Eighty middle class families (39 girls) drawn from a community sample participated. Children (M = 25.34 months, SD = 1.04) wore an actigraph monitor (Mini-Mitter® Actiwatch Actigraph, Respironics) for a 72-h period, and mothers completed a sleep diary during the same period. Eighty-nine percent of the mothers and 75% of the fathers also filled out the CBCL (1.5–5). Mother and father CBCL scores were highly correlated. Overall, good correspondence was found between the CBCL filled out by mothers and sleep efficiency and duration derived from maternal sleep diaries (r between −0.39 and −0.25, p ≤ 0.05). Good correspondence was also found between the CBCL filled out by fathers and sleep efficiency as derived from maternal sleep diaries (r between −0.39 and −0.24, p ≤ 0.05), but not with sleep duration (all results were non-significant). Very few correlations between actigraphy and the CLBL scores reached statistical significance. The Bland and Altman method revealed that sleep diaries and actigraphy showed poor agreement with one another when assessing sleep duration and sleep efficiency. However, diary- and actigraphy-derived sleep durations were significantly correlated. Consistent with findings among older groups of children, this study suggests that the CBCL sleep items, sleep diaries, and actigraphy tap into quite different aspects of sleep among toddlers. The choice of which measures to use should be based on the exact aspects of sleep that one aims to assess. Overall, despite its frequent use, the composite sleep score of the CBCL shows poor links to objective measures of sleep duration and sleep efficiency.
actigraphy; sleep diary; CBCL; sleep; toddlers; agreement
Infants who are born small for gestational age (SGA) are at risk for developmental delays, which may be related to deficiencies in zinc, an essential trace metal, or to deficiencies in their ability to elicit caregiver responsiveness (functional isolation hypothesis). The objective of this study was to evaluate at 6 and 10 months of age the impact of a 9-month supplementation trial of 5 mg of zinc on the development and behavior of infants who were born SGA and to evaluate infants’ ability to elicit responsive caregiver behavior.
A randomized, controlled trial of zinc supplementation was conducted among 200 infants in a low-income, urban community in Delhi, India. Infants were recruited when they were full term (>36 weeks) and SGA (birth weight <10th percentile weight-for-gestational age). Infants were randomized to receive daily supplements of a micronutrient mix (folate, iron, calcium, phosphorus, and riboflavin) with or without 5 mg of zinc sulfate. The supplement was administered by field workers daily from 30 days to 9 months of age. At 6 and 10 months, infant development and behavior were measured in a clinical setting using the Bayley Scales of Infant Development II. Caregiver responsiveness, observed on an Indian version of the Home Observation for Measurement of the Environment scale, was measured during a home visit at 10 months. During both the clinic and home visits, caregivers reported on their infant’s temperament.
There were no direct effects of zinc supplementation on the infants’ development or behavior at either 6 or 10 months. In a subgroup analysis among the zinc-supplemented infants, lower birth weight infants were perceived to be more temperamentally difficult than higher weight infants; in the control group, birth weight was not associated with temperament. Heavier birth weight infants had better scores on all measures of development and behavior at 6 months and on changes in mental and motor development from 6 to 10 months, compared with lighter birth weight infants. Boys had better weight gain and higher scores on mental development and emotional regulation than girls. Infants who were from families of higher socioeconomic status (indexed by parental education, house size, and home ownership) had higher scores on mental development and orientation/engagement (exploratory behavior) than infants who were from families of lower socioeconomic status. In keeping with the functional isolation hypothesis, caregiver responsiveness was associated with infant irritability, controlling for socioeconomic status, gender, birth weight, and weight gain. Responsive mothers were more likely to perceive their infants to be temperamentally easy than less responsive mothers.
Possible explanations for the lack of effects of zinc supplementation on infant development and behavior include 1) subtle effects of zinc supplementation that may not have been detected by the Bayley Scales, 2) interference with other nutritional deficiencies, or 3) no impact of zinc deficiency on infants’ development and behavior. The link between birth weight and irritability among infants in the zinc supplementation group suggests that the response to zinc supplementation may differ by birth weight, with irritability occurring among the most vulnerable infants. Longer term follow-up studies among zinc-supplemented infants are needed to examine whether early supplementation leads to developmental or behavioral changes that have an impact on school-age performance. The relationship between infant irritability and low maternal responsiveness lends support to the functional isolation hypothesis and the importance of asking caregivers about infant temperament.
zinc deficiency; cognitive development; mental development; motor development; behavior; temperament; maternal responsiveness
To investigate temperament in infants whose mothers were exposed to Hurricane Katrina and its aftermath, and to determine if high hurricane exposure is associated with difficult infant temperament. A prospective cohort study of women giving birth in New Orleans and Baton Rouge, LA (n=288) in 2006–2007 was conducted. Questionnaires and interviews assessed the mother’s experiences during the hurricane, living conditions, and psychological symptoms, two months and 12 months postpartum. Infant temperament characteristics were reported by the mother using the activity, adaptability, approach, intensity, and mood scales of the Early Infant and Toddler Temperament Questionnaires, and “difficult temperament” was defined as scoring in the top quartile for three or more of the scales. Logistic regression was used to examine the association between hurricane experience, mental health, and infant temperament. Serious experiences of the hurricane did not strongly increase the risk of difficult infant temperament (association with 3 or more serious experiences of the hurricane: adjusted odds ratio (aOR) 1.50, 95% confidence interval (CI) 0.63–3.58 at 2 months; 0.58, 0.15–2.28 at 12 months). Maternal mental health was associated with report of difficult infant temperament, with women more likely to report having a difficult infant temperament at one year if they had screened positive for PTSD (aOR 1.82, 95% confidence interval (CI) 0.61–5.41), depression, (aOR 3.16, 95% CI 1.22–8.20) or hostility (aOR 2.17, 95% CI 0.81–5.82) at 2 months. Large associations between maternal stress due to a natural disaster and infant temperament were not seen, but maternal mental health was associated with reporting difficult temperament. Further research is needed to determine the effects of maternal exposure to disasters on child temperament, but in order to help babies born in the aftermath of disaster, the focus may need to be on the mother’s mental health.
infant temperament; natural disaster; postpartum depression; post-traumatic stress disorder
Because early life growth has long-lasting metabolic and behavioral consequences, intervention during this period of developmental plasticity may alter long-term obesity risk. While modifiable factors during infancy have been identified, until recently, preventive interventions had not been tested. The Intervention Nurses Starting Infants Growing on Healthy Trajectories (INSIGHT). Study is a longitudinal, randomized, controlled trial evaluating a responsive parenting intervention designed for the primary prevention of obesity. This “parenting” intervention is being compared with a home safety control among first-born infants and their parents. INSIGHT’s central hypothesis is that responsive parenting and specifically responsive feeding promotes self-regulation and shared parent–child responsibility for feeding, reducing subsequent risk for overeating and overweight.
316 first-time mothers and their full-term newborns were enrolled from one maternity ward. Two weeks following delivery, dyads were randomly assigned to the “parenting” or “safety” groups. Subsequently, research nurses conduct study visits for both groups consisting of home visits at infant age 3–4, 16, 28, and 40 weeks, followed by annual clinic-based visits at 1, 2, and 3 years. Both groups receive intervention components framed around four behavior states: Sleeping, Fussy, Alert and Calm, and Drowsy. The main study outcome is BMI z-score at age 3 years; additional outcomes include those related to patterns of infant weight gain, infant sleep hygiene and duration, maternal responsiveness and soothing strategies for infant/toddler distress and fussiness, maternal feeding style and infant dietary content and physical activity. Maternal outcomes related to weight status, diet, mental health, and parenting sense of competence are being collected. Infant temperament will be explored as a moderator of parenting effects, and blood is collected to obtain genetic predictors of weight status. Finally, second-born siblings of INSIGHT participants will be enrolled in an observation-only study to explore parenting differences between siblings, their effect on weight outcomes, and carryover effects of INSIGHT interventions to subsequent siblings.
With increasing evidence suggesting the importance of early life experiences on long-term health trajectories, the INSIGHT trial has the ability to inform future obesity prevention efforts in clinical settings.
NCT01167270. Registered 21 July 2010.
Obesity; Prevention; Infancy; Responsiveness; Home visitation; Feeding; Parenting
Indicators of temperament appear early in infancy and remain relatively stable over time. Despite a great deal of interest in biological indices of temperament, most studies of infant temperament rely on parental reports or behavioral tasks. Thus, the extent to which commonly used temperament measures relate to potential biological indicators of infant temperament is still relatively unknown. The current experiment examines the relationship between a common parental report measure of temperament – the Infant Behavior Questionnaire – Revised (IBQ-R) – and measures of frontal EEG asymmetry in infants. We examined associations between the subscales of the IBQ-R and frontal EEG asymmetry scores recorded during a combined series of neutral attentional and putatively emotional recording conditions in infants between 7 and 9 months of age. We predicted that approach-related subscales of the IBQ-R (e.g., Approach, Soothability) would be related to greater left prefrontal asymmetry, while withdrawal-related subscales (e.g., Distress to Limitations, Fear, Falling Reactivity, Perceptual Sensitivity) would be related to greater right prefrontal asymmetry. In the mid- and lateral-frontal regions, Approach, Distress to Limitations, Fear, Soothability, and Perceptual Sensitivity were generally associated with greater left frontal activation (rs≥.23, ps<0.05), while only Falling Reactivity was associated with greater right frontal activation (rs≤−.44, ps<0.05). Results suggest that variability in frontal EEG asymmetry is robustly associated with parental report measures of temperament in infancy.
Recent findings in infant rats suggest that the preoptic area (POA) and/or basal forebrain (BF) contribute to developmental changes in sleep and wake organization between postnatal day 2 (P2) and P9. To examine the contributions of these forebrain areas to sleep and wakefulness, separate lesions of the POA or BF, or combined lesions (POA+BF), were performed at P9, and precollicular transections were performed at P2. In addition, modafinil, a drug of unknown mechanism of action whose effects on sleep and wakefulness have been hypothesized to result from inhibition of POA activity, was administered at P2 and P9. Finally, extracellular neuronal activity was recorded from the POA and BF. POA lesions decreased sleep bout durations and increased wake bout durations. BF lesions inhibited sleep bout durations to a lesser extent, while leaving wake bout durations unaffected. POA+BF lesions produced a combination of these effects, resulting in short bouts of sleep and wakefulness similar to those of transected P8 rats. Even at P2, transections decreased sleep bout durations. The finding, however, that the sleep-inhibiting and wake-promoting effects of modafinil were more potent at P9 than at P2 suggests increasing sleep-wake modulation by the POA between these two ages. Finally, neuronal recordings confirmed the presence of state-dependent neurons within the infant POA and BF. We propose that the POA, in addition to promoting sleep, inhibits wakefulness via direct and indirect inhibitory connections with wake-promoting neurons in the BF, and that this inhibitory influence increases across early development.
REM; atonia; modafinil; development; neurophysiology
This study aimed to identify and compare differences in temperament and maternal stress between infants with complex congenital heart disease (CHD) and healthy controls at 3 months of age.
Study sample was drawn from an existing longitudinal study examining growth in infants with CHD as compared to healthy controls. Infant temperament and parental stress were measured in 129 mother-infant dyads. Inclusion criteria for infants with CHD were ≥ 36 weeks post-menstrual age, ≥ 2500 grams at birth, surgery in first 6 weeks of life, and no major congenital anomalies or genetic syndromes. The Early Infancy Temperament Questionnaire and Parent Stress Index were the assessment tools used.
Infants with single ventricle (SV) physiology were more negative in mood (F=7.14, p<0.001) and less distractible (F=5.00, p<0.008) than the biventricular physiology (BV) or control (C) infant groups. The demands of care for infants with CHD was a source of stress as compared to control infants (p<.05). Five of six subscales of the Child Domain were significant sources of stress in the SV group compared to BV and Control groups. Negative mood and difficulty to soothe were predictors for Child Domain and Total Life Stress in SV infants.
The demands of parenting an irritable infant with SV physiology puts these mothers at risk for high levels of stress. Results suggest the need for pre-discharge anticipatory guidance for parents to better understand and respond to the behavioral style of their infants, in particular, infants with SV physiology.
infant temperament; parent stress; complex congenital heart disease; burden of care
Objective To determine whether the probiotic Lactobacillus reuteri DSM 17938 reduces crying or fussing in a broad community based sample of breastfed infants and formula fed infants with colic aged less than 3 months.
Design Double blind, placebo controlled randomised trial.
Setting Community based sample (primary and secondary level care centres) in Melbourne, Australia.
Participants 167 breastfed infants or formula fed infants aged less than 3 months meeting Wessel’s criteria for crying or fussing: 85 were randomised to receive probiotic and 82 to receive placebo.
Interventions Oral daily L reuteri (1×108 colony forming units) versus placebo for one month.
Main outcomes measures The primary outcome was daily duration of cry or fuss at 1 month. Secondary outcomes were duration of cry or fuss; number of cry or fuss episodes; sleep duration of infant at 7, 14, and 21 days, and 1 and 6 months; maternal mental health (Edinburgh postnatal depression subscale); family functioning (paediatric quality of life inventory), parent quality adjusted life years (assessment of quality of life) at 1 and 6 months; infant functioning (paediatric quality of life inventory) at 6 months; infant faecal microbiota (microbial diversity, colonisation with Escherichia coli), and calprotectin levels at 1 month. In intention to treat analyses the two groups were compared using regression models adjusted for potential confounders.
Results Of 167 infants randomised from August 2011 to August 2012, 127 (76%) were retained to primary outcome; of these, a subset was analysed for faecal microbial diversity, E coli colonisation, and calprotectin levels. Adherence was high. Mean daily cry or fuss time fell steadily in both groups. At 1 month, the probiotic group cried or fussed 49 minutes more than the placebo group (95% confidence interval 8 to 90 minutes, P=0.02); this mainly reflected more fussing, especially for formula fed infants. The groups were similar on all secondary outcomes. No study related adverse events occurred.
L reuteri DSM 17938 did not benefit a community sample of breastfed infants and formula fed infants with colic. These findings differ from previous smaller trials of selected populations and do not support a general recommendation for the use of probiotics to treat colic in infants.
Trial registration Current Controlled Trials ISRCTN95287767.
Prospective studies linking infant temperament, or behavioral style, to infant body composition are lacking. In this longitudinal study (3 to 18 months), we seek to examine the associations between two dimensions of infant temperament (distress to limitations and activity level) and two anthropometric indicators (weight-for-length z-scores (WLZ) and skin fold (SF) measures) in a population at high risk of overweight.
Data are from the Infant Care and Risk of Obesity Project, a longitudinal study of North Carolina low income African American mother-infant dyads (n = 206). Two temperament dimensions were assessed using the Infant Behavior Questionnaire-Revised. A high distress to limitations score denotes an infant whose mother perceives that s/he often cries or fusses, and a high activity level score one who moves his/her limbs and squirms frequently. Cross-sectional analyses were conducted using ordinary least squares regression. Fixed effects longitudinal models were used to estimate anthropometric outcomes as a function of time varying infant temperament.
In longitudinal models, increased activity levels were associated with later decreased fatness and WLZ. In contrast, high levels of distress to limitations were associated with later increased fatness at all time points and later increased WLZ at 12 months.
Infant temperament dimensions contribute to our understanding of the role of behavior in the development of the risk of overweight in the formative months of life. Identification of modifiable risk factors early in life may help target strategies for establishing healthy lifestyles prior to the onset of overweight.
In the pediatric literature, excessive crying has been reported solely in association with 3-month colic and is described, if at all, as unexplained crying and fussing during the first 3 months of life. The bouts of crying are generally thought to be triggered by abdominal colic (over-inflation of the still immature gastrointestinal tract), and treatment is prescribed accordingly. According to this line of reasoning, excessive crying is harmless and resolves by the end of the third month without long-term consequences. However, there is evidence that it may cause tremendous distress in the mother-infant relationship, and can lead to disorders of behavioral and emotional regulation at the toddler stage (such as sleep and feeding disorders, chronic fussiness, excessive clinginess, and temper tantrums). Early treatment of excessive crying focuses on parent-infant communication, and parent-infant interaction in the context of soothing and settling the infant to sleep is a promising approach that may prevent later behavioral and emotional disorders in infancy.
Excessive crying; Behavioral and emotional regulation disorder; Infant
Currently, about 10% of infants have a weight for length greater
than the 95th percentile for their age and sex, which puts them at risk for
obesity as they grow. In a pilot obesity prevention study, primiparous mothers
and their newborn infants were randomly assigned to a control group or a
Soothe/Sleep intervention. Previously, it has been demonstrated that this
intervention contributed to lower weight-for-length percentiles at 1 year; the
aim of the present study was to examine infant behavior diary data collected
during the intervention. Markov modeling was used to characterize
infants’ patterns of behavioral transitions at ages 3 and 16 weeks.
Results showed that heavier mothers were more likely to follow their
infants’ fussing/crying episodes with a feeding. The intervention
increased infants’ likelihood of transitioning from a fussing/crying
state to an awake/calm state. A shorter latency to feed in response to
fussing/crying was associated with a higher subsequent weight status. This study
provides preliminary evidence that infants’ transitions out of
fussing/crying are characterized by inter-individual differences, are
modifiable, and are linked to weight outcomes, suggesting that they may be
promising targets for early behavioral obesity interventions, and highlighting
the methodology used in this study as an appropriate and innovative tool to
assess the impact of such interventions.
Narcolepsy, a disorder characterized by fragmented bouts of sleep and wakefulness during the day and night as well as cataplexy, has been linked in humans and non-human animals to the functional integrity of the orexinergic system. Adult orexin knockout mice and dogs with a mutation of the orexin receptor exhibit symptoms that mirror those seen in narcoleptic humans. As with narcolepsy, infant sleep-wake cycles in humans and rats are highly fragmented, with consolidated bouts of sleep and wakefulness developing gradually. Based on these common features of narcoleptics and infants, we hypothesized that the development of sleep-wake fragmentation in orexin knockout mice would be expressed as a developmental divergence between knockouts and wild-types, with the knockouts lagging behind the wild-types. We tested this hypothesis by recording the sleep-wake patterns of infant orexin knockout and wild-type mice across the first three postnatal weeks. Both knockouts and wild-types exhibited age-dependent, and therefore orexin-independent, quantitative and qualitative changes in sleep-wake patterning. At 3 weeks of age, however, by which time the sleep and wake bouts of the wild-types had consolidated further, the knockouts lagged behind the wild-types and exhibited significantly more bout fragmentation. These findings suggest the possibility that the fragmentation of behavioral states that characterizes narcolepsy in adults reflects reversion back toward the more fragmented sleep-wake patterns that characterize infancy.
orexin; hypocretin; atonia; development; knockout; mouse
The objectives of this study were to: (1) describe the longitudinal development of sleep-wake patterns of solitary-sleeping infants from 1 to 12 months of age, (2) identify effects on sleep patterns and on self-soothing behaviors of introducing a novel sleep aid, and (3) identify predictive factors of self-soothing at 12 months using a transactional model as a guide.
Eighty infants’ nighttime sleep-wake patterns and associated variables were studied at 5 times across the first year of life using videosomnography and questionnaires.
Sleep-wake state developmental changes, as reported in investigations of infant sleep, were replicated, although a great deal of individual variability in the development of all sleep-related variables was noted. No major effects on sleep or on self-soothing behavior were evident from the introduction of the novel sleep aid. Three variables were identified as significant predictors of self-soothing at 12 months: decreasing amounts of time spent out of crib across the first year, high levels of quiet sleep at birth, and longer parental response times to infant awakenings at 3 months.
These data lend preliminary support for the transactional model and suggest that infant and parental factors interact to influence the development of self-soothing.
Infancy; normal development; parent-child interaction; paediatrics; sleep; temperament; AS: active sleep; AW: wakefulness; BDI: Beck Depression Inventory; GLM: general linear modeling; LSP: longest sleep period; OOC: out of crib; PSOCS: Parenting Sense of Competence Scale; QS: quiet sleep; RSA: representational sleep aid; SC: sham control; SS: self-soothed; TST: total sleep time
Background & Methods
To examine the relationship between breastfeeding and maternally-rated infant temperament at age 3 months, 316 infants in the prospective Cambridge Baby Growth Study, UK had infant temperament assessed at age 3 months by mothers using the Revised Infant Behavior Questionnaire, which produces scores for three main dimensions of temperament derived from 14 subscales. Infant temperament scores were related to mode of infant milk feeding at age 3 months (breast only; formula milk only; or mixed) with adjustment for infant's age at assessment and an index of deprivation.
Infant temperament dimension scores differed across the three infant feeding groups, but appeared to be comparable between exclusive breast-fed and mixed-fed infants. Compared to formula milk-fed infants, exclusive breast-fed and mixed-fed infants were rated as having lower impulsivity and positive responses to stimulation (adjusted mean [95% CI] “Surgency/Extraversion” in formula-fed vs. mixed-fed vs. breast-fed groups: 4.3 [4.2–4.5] vs. 4.0 [3.8–4.1] vs. 4.0 [3.9–4.1]; p-heterogeneity = 0.0006), lower ability to regulate their own emotions (“Orienting/Regulation”: 5.1 [5.0–5.2], vs. 4.9 [4.8–5.1] vs. 4.9 [4.8–5.0]; p = 0.01), and higher emotional instability (“Negative affectivity”: 2.8 [2.6–2.9] vs. 3.0 [2.8–3.1] vs. 3.0 [2.9–3.1]; p = 0.03).
Breast and mixed-fed infants were rated by their mothers as having more challenging temperaments in all three dimensions; particular subscales included greater distress, less smiling, laughing, and vocalisation, and lower soothability. Increased awareness of the behavioural dynamics of breastfeeding, a better expectation of normal infant temperament and support to cope with difficult infant temperament could potentially help to promote successful breastfeeding.