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201.
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. 相似文献
202.
AimIn a Nepalese setting, to measure the reliability of the Test of Infant Motor Performance (TIMP) and its ability to predict development scores at 6 months.MethodsNepalese infants (n = 705) were assessed by the TIMP when they were 8–12 weeks old and the Bayley Scales of Infant and Toddler Development, 3rd edition (Bayley-III) at 6 months. Inter-rater agreement was expressed by intraclass correlation coefficients (ICCs), the internal consistency by Cronbach’s alphas and Pearson correlation coefficients. Predictive ability was estimated in linear regression models.ResultsInter-rater agreement was excellent (ICCs > 0.93). Alphas for the TIMP total scores were 0.76 for infants born to term and 0.72 in those born preterm. Correlation coefficients between TIMP total and Bayley-III subscale-scores ranged from 0.05 to 0.28 for term infants and from 0.15 to 0.43 for preterm infants. Using American norms, 56.3 % had TIMP scores within average and 43.7 % below average range. Bayley-III subscale scores were lower in children with TIMP scores below the average range, with the strongest estimates for Gross motor and Socio-emotional development.InterpretationThe reliability of the TIMP was acceptable, and the TIMP could be a feasible tool to monitor infant motor development in low-resource settings. Properties of the TIMP differed according to gestational age. 相似文献
203.
This longitudinal study examines the association between fetal Selective Serotonergic Reuptake Inhibitor antidepressant exposure and infant sleep behaviours at six and 12 months of age and focus on three of the most commonly prescribed antidepressants in pregnancy.This study utilises data on 698 women recruited at less than 20 weeks of pregnancy and are followed up at six and 12 months postpartum. Women were recruited into one of three groups: those taking either sertraline, citalopram or escitalopram antidepressants in pregnancy (n = 85); women with a depressive disorder who were not taking antidepressants (non-medicated depressed, NMD; n = 82); and, and a control group of women (n = 531). At six and 12 months, data were collected on breastfeeding and sleep location and infant sleep was measured using the Brief Infant Sleep Questionnaire. Antidepressants sertraline, escitalopram and citalopram were not associated with increased infant waking or time awake. However, sertraline was associated with longer time for an infant to go to sleep.This study provides reassurance that SSRI antidepressants and, in particular, sertraline, escitalopram and citalopram are not associated with infant sleep behaviours that are commonly regarded as problematic including night waking. Further replication of these findings, including with direct measures of infant sleep, are recommended. 相似文献
204.
Early self-regulation is a foundation for lifelong wellness and can be shaped by the interplay among several vital exposures. In this study, we examined the emergence of reliable profiles based upon exposure to risk and protective factors in infancy, determined if sociodemographic resources predict profile membership, and determined if these profiles predict early regulatory behaviors in a sample of infants reared in low-income homes. Data were collected from a sample of primarily Black or White mother-infant dyads living in low-income homes in the Midwest (n = 222) during the infants’ first year of life (mean maternal age at enrollment: 26.29 years; range 18−43 years). Exposures included mother-infant interactions; father support; maternal depression, stress, and self-efficacy; home environment; food security; and breastfeeding duration. Sociodemographic resources included poverty status; economic hardship; maternal education, employment, and age; parental marital status; and infant race and sex. Infant regulatory behaviors were measured with the Infant Behavior Questionnaire-Revised Very Short Form effortful control subscale (mean age 11 months; range 8.5−14.3 months). Latent profile analysis was used to profile infants by risk and protective exposures. Regression was used to differentiate profiles by sociodemographic resources and to predict infant regulatory behavior from profiles. Three profiles emerged: low father support, good maternal mental health, and poor maternal mental health. A married mother, less economic hardship, and working mothers predicted infant exposure to good maternal mental health. Infant regulatory behavior was best when the infant was exposed to the good maternal mental health profile. Implications for future research are discussed. 相似文献
205.
Touchscreen use amongst young children has proliferated in recent years, yet little is known about the association between daily touchscreen exposure and inhibitory control in the first year of life. Previous research has found a negative association between the amount of television viewing and inhibitory control in early childhood, but it is unclear whether negative associations with screen use extend to touchscreens. The current study presents an exploratory analysis of the cross-sectional associations between inhibitory control and the amount of touchscreen use amongst 10-month-olds (n = 128–156). Touchscreen exposure was assessed via parent-report. In order to include a range of “hot” and “cool” aspects of inhibitory control, these skills were assessed using lab-based response inhibition and prohibition tasks as well as parent-reported observations of infants’ inhibitory control abilities and broader regulatory behaviors. A “Cognitive Executive Function (EEFQ-CEF)” score (encompassing Inhibitory Control, Flexibility, and Working Memory items) was included as a secondary broader executive function construct to examine whether effects showed specificity to inhibitory control rather than executive functions more generally. Correlation analyses indicated no association between touchscreen exposure and the four indices of IC. However, a positive association was found for the amount of touchscreen exposure and EEFQ-CEF once accounting for sociodemographic variables. The implications of these findings and future directions are discussed. 相似文献
206.
The present research investigated whether six-month-olds who rarely produce pointing actions can detect the object-directedness and communicative function of others’ pointing actions when linguistic information is provided. In Experiment 1, infants were randomly assigned to either a novel-word or emotional-vocalization condition. They were first familiarized with an event in which an actor uttered either a novel label (novel-word condition) or exclamatory expression (emotional-vocalization condition) and then pointed to one of two objects. Next, the positions of the objects were switched. During test trials, each infant watched the new-referent event where the actor pointed to the object to which the actor had not pointed before or the old-referent event where the actor pointed to the old object in its new location. Infants in the novel-word condition looked reliably longer at the new-referent event than at the old-referent event, suggesting that they encoded the object-directedness of the actor’s point. In contrast, infants in the emotional-vocalization condition showed roughly equal looking times to the two events. To further examine infants’ understanding of the communicative aspect of an actor’s point using a different communicative context, Experiment 2 used an identical procedure to the novel-word condition in Experiment 1, except there was only one object present during the familiarization trials. When the familiarization trials did not include a contrasting object, we found that the communicative intention of the actor’s point could be ambiguous. The infants showed roughly equal looking times during the two test events. The current research suggests that six-month-olds understand the object-directedness and communicative intention of others’ pointing when presented with a label, but not when presented with an emotional non-speech vocalization. 相似文献
207.
Evidence suggests that increased use of screens early in life may have negative developmental consequences for children. However, little is known concerning parental factors that predict initial screen exposure in infancy. The primary goal of this study was to examine whether parental educational attainment and maternal stress were associated with infant screen exposure by 6 months of age. A diverse sample of mothers (N = 93) was recruited prenatally. In a follow-up visit when the infants were six months of age (N = 82), we examined factors that may be associated with initial infant exposure to screens. First, mothers reported whether they had already exposed their infants to screens. Thereafter, those mothers who reported already having exposed their infants to screens were further queried to determine the extent of infant screen use. Results demonstrated that among infants exposed to screens, mothers reported an average of nearly 3 h of daily screen use. Average parental educational attainment, but not maternal stress, was significantly associated with initial infant exposure. Of those families who endorsed screen exposure by 6 months, 70 % reported a screen in the room where the child sleeps, nearly half reported using screens to help calm the infant, and about a third reported using a screen at least sometimes during meals, when going to sleep, and while waiting. Parental education around infant screen use behaviors may be important to help promote child development and outcomes. 相似文献
208.
This study examined associations between objectively-measured nighttime sleep duration and physical activity in a sample of 6–7 month-old infants (N=93). The study also investigated relationships between infant sleep and demographic and environmental characteristics. Cross-sectional relationships were assessed using linear regression analyses. Nighttime sleep duration was positively associated with physical activity levels. Nighttime sleep duration was greater when infants had a consistent bedtime, slept in a separate room, were male, and had mothers who reported having a college education or greater. These findings can inform the development of interventions that aim to improve infant sleep. 相似文献
209.
The use of electroencephalography (EEG) to study infant brain development is a growing trend. In addition to classical longitudinal designs that study the development of neural, cognitive and behavioural functions, new areas of EEG application are emerging, such as novel social neuroscience paradigms using dual infant-adult EEG recordings. However, most of the experimental designs, analysis methods, as well as EEG hardware were originally developed for single-person adult research. When applied to study infant development, adult-based solutions often pose unique problems that may go unrecognised. Here, we identify 14 challenges that infant EEG researchers may encounter when designing new experiments, collecting data, and conducting data analysis. Challenges related to the experimental design are: (1) small sample size and data attrition, and (2) varying arousal in younger infants. Challenges related to data acquisition are: (3) determining the optimal location for reference and ground electrodes, (4) control of impedance when testing with the high-density sponge electrode nets, (5) poor fit of standard EEG caps to the varying infant head shapes, and (6) ensuring a high degree of temporal synchronisation between amplifiers and recording devices during dual-EEG acquisition. Challenges related to the analysis of longitudinal and social neuroscience datasets are: (7) developmental changes in head anatomy, (8) prevalence and diversity of infant myogenic artefacts, (9) a lack of stereotypical topography of eye movements needed for the ICA-based data cleaning, (10) and relatively high inter-individual variability of EEG responses in younger cohorts. Additional challenges for the analysis of dual EEG data are: (11) developmental shifts in canonical EEG rhythms and difficulties in differentiating true inter-personal synchrony from spurious synchrony due to (12) common intrinsic properties of the signal and (13) shared external perturbation. Finally, (14) there is a lack of test-retest reliability studies of infant EEG. We describe each of these challenges and suggest possible solutions. While we focus specifically on the social neuroscience and longitudinal research, many of the issues we raise are relevant for all fields of infant EEG research. 相似文献
210.
Preliminary evidence suggests that changes in DNA methylation, a widely studied epigenetic mechanism, contribute to the etiology of Autism Spectrum Disorder (ASD). However, data is primarily derived from post-mortem brain samples or peripheral tissue from adults. Deep-phenotyped longitudinal infant cohorts are essential to understand how epigenetic modifications relate to early developmental trajectories and emergence of ASD symptoms. We present a proof-of-principle study designed to evaluate the potential of prospective epigenetic studies of infant siblings of children with ASD.Illumina genome-wide 450 K DNA methylation data from buccal swabs was generated for 63 male infants at multiple time-points from 8 months to 2 years of age (total N = 107 samples). 11 of those infants received a diagnosis of ASD at 3 years. We conducted a series of analyses to characterize DNA methylation signatures associated with categorical outcome and neurocognitive measures from parent-report questionnaire, eye-tracking and electro-encephalography.Effects observed across the entire genome (epigenome-wide association analyses) suggest that collecting DNA methylation samples within infant-sibling designs allows for the detection of meaningful signals with smaller sample sizes than previously estimated. Mapping networks of co-methylated probes associated with neural correlates of social attention implicated enrichment of pathways involved in brain development. Longitudinal modelling found covariation between phenotypic traits and DNA methylation levels in the proximity of genes previously associated with cognitive development, although larger samples and more complete datasets are needed to obtain generalizable results.In conclusion, assessment of DNA methylation profiles at multiple time-points in infant-sibling designs is a promising avenue to comprehend developmental origins and mechanisms of ASD. 相似文献