LR Infants Research Articles

Adverse infant outcomes following low-risk pregnancies in England: a retrospective cohort study

BackgroundThere are limited data describing adverse infant outcomes in infants born to women with a low risk of complications during pregnancy, such as those who may be enrolled in maternal immunization trials. This retrospective study estimated incidence proportions of infant outcomes in different cohorts of liveborn infants in England between 2005 and 2017.MethodsThe incidence proportions of 10 infant outcomes were calculated for liveborn infants from pregnancies represented in the Clinical Practice Research Datalink (CPRD) Mother-Baby Link (MBL) and linkage to Hospital Episode Statistics (HES). Three infant cohorts were designed: (1) the all pregnancies infants cohort (N = 185,119), (2) the all pregnancies with a gestational age (GA) ≥ 24 weeks infants cohort (N = 183,869), and (3) the low-risk pregnancies infants cohort (LR infants cohort, N = 121,871), which included pregnancies with a GA ≥ 24 weeks and no diagnosis of predefined high-risk medical conditions until 24 weeks GA.ResultsThe most common adverse infant outcome in the three infant cohorts was macrosomia (e.g., 1,085.9/10,000 live births in the LR infants cohort), followed by minor congenital anomalies (e.g., 800.6/10,000 in the LR infants cohort), very low/low birth weight (e.g., 400.6/10,000 in the LR infants cohort), and major congenital anomalies (e.g., 270.4/10,000 in the LR infants cohort). The incidence proportions for early-onset sepsis, very low/low birth weight, and minor and major congenital anomalies were lower in the LR infants than in the other cohorts (non-overlapping confidence intervals [CIs]). The incidence proportions of neonatal death, infant death, late-onset sepsis, macrosomia, small for GA, and large for GA were similar between cohorts (overlapping CIs).ConclusionsThis study generated background rates of adverse infant outcomes from liveborn infants of all and low-risk pregnancies represented in the CPRD Pregnancy Register MBL and linkage to HES. The results indicate lower incidence proportions of several adverse infant outcomes in infants from low-risk pregnancies compared to all pregnancies, illustrating the importance of considering maternal risk factors. These background rates may facilitate the interpretation of safety data from maternal immunization trials and of pharmacovigilance data from maternal vaccines. They may also be of interest for other interventions studied in pregnant women.

Elevated serum AST and LDH levels are associated with infant death in premature babies with neonatal leukemoid reaction: a cohort study.

Neonatal leukemoid reaction (NLR) is often accompanied by infectious or non-infectious diseases, a low birth weight, sepsis, prematurity, ventricular hemorrhage, and bronchial dysplasia. It has an incidence rate of 1.3-15% and a mortality rate of about 41.4%. Previous studies on NLR have largely focused on its pathogenesis and clinical cases, but little is known about its prognostic laboratory indicators. We found that some of the NLR exhibited obviously elevation in liver function tests like aspartate transaminase (AST) and lactate dehydrogenase (LDH) which were not took by all the LR infants. The necessity for liver function tests for the prognosis of NLR was still unclear. A total of 39 premature infants with NLR at the First Hospital of Jilin University between March 2016 and March 2017 were included in this retrospective cohort study. The infants were divided into death and cured group based on the clinical outcomes. Premature infants with LR and death were defined as the case group (n=14), while infants without death were defined as the control group (n=25). Confounding factors such as age and gender between the two groups were controlled. Blood routine tests, including the white blood cell (WBC) count and subtypes, and liver function, and clinical features were recorded and analyzed. T tests were used to examine the differences in the laboratory indicators between the NLR and control groups. Receiver operating characteristic curves (ROCs) and areas under the curve (AUCs) were used to examine laboratory indicators for prognosis. For predicting clinical outcomes, the ROC curves showed that the cut-off values for AST and LDH were 279 and 1,412 U/L, respectively. The sensitivity and specificity for AST were 92% and 71.43%, respectively, with an AUC of 0.894, while the sensitivity and specificity for LDH were 88% and 78.57%, respectively, with an AUC of 0.911. This innovative study investigated the NLR prognosis depending on laboratory tests. We found that serum AST and LDH levels had reliable predictive value in determining adverse outcomes of NLR.

Infant vocalizing and phenotypic outcomes in autism: Evidence from the first 2years.

Infant vocalizations are early-emerging communicative markers shown to be atypical in autism spectrum disorder (ASD), but few longitudinal, prospective studies exist. In this study, 23,850 infant vocalizations from infants at low (LR)- and high (HR)-risk for ASD (HR-ASD=23, female=3; HR-Neg=35, female=13; LR=32, female=10; 80% White; collected from 2007 to 2017 near Philadelphia) were analyzed at 6, 12, and 24months. At 12months, HR-ASD infants produced fewer vocalizations than HR-Neg infants. From 6 to 24months, HR-Neg infants demonstrated steeper vocalization growth compared to HR-ASD and LR infants. Finally, among HR infants, vocalizing at 12months was associated with language, social phenotype, and diagnosis at age 2. Infant vocalizing is an objective behavioral marker that could facilitate earlier detection of ASD.

Variability in Responding to Joint Attention Cues in the First Year is Associated With Autism Outcome.

With development, infants become increasingly responsive to the many attention-sharing cues of adults; however, little work has examined how this ability emerges in typical development or in the context of early autism spectrum disorder (ASD). This study characterized variation in the type of cue needed to elicit a response to joint attention (RJA) using the Dimensional Joint Attention Assessment (DJAA) during naturalistic play. We measured the average redundancy of cue type required for infants to follow RJA bids from an experimenter, as well as their response consistency, in 268 infants at high (HR, n= 68) and low (LR, N= 200) familial risk for ASD. Infants were assessed between 8 and 18 months of age and followed up with developmental and clinical assessments at 24 or 36 months. Our sample consisted of LR infants, as well as HR infants who did (HR-ASD) and did not (HR-neg) develop ASD at 24 months. We found that HR and LR infants developed abilities to respond to less redundant (more sophisticated) RJA cues at different rates, and that HR-ASD infants displayed delayed abilities, identifiable as early as 9 months, compared to both HR-neg and LR infants. Interestingly, results suggest that HR-neg infants may exhibit a propensity to respond to less redundant (more sophisticated) RJA cues relative to both HR-ASD and LR infants. Using an approach to characterize variable performance of RJA cue-reading abilities, findings from this study enhance our understanding of both typical and ASD-related proficiencies and deficits in RJA development.

Object exploration during the transition to sitting: A study of infants at heightened risk for autism spectrum disorder.

Learning to sit promotes infants' object exploration because it offers increased access to objects and an improved position for exploration (e.g., ). Infants at heightened risk (HR) for autism spectrum disorder (ASD) exhibit delays in sitting and differences in object exploration. However, little is known about the association between sitting and object exploration among HR infants. We examined changes in object exploration as HR infants (N=19) and comparison infants with no family history of ASD (Low Risk; LR; N=23) gained experience sitting independently. Infants were observed monthly from 2.5months until 1month after the onset of independent sitting. At 12, 18, 24, and 36months, infants completed standardized developmental assessments, and HR infants were assessed for ASD symptoms at 36months. Although HR infants began sitting later than LR infants, both groups increased time spent grasping, shaking, banging, and mouthing objects as they gained sitting experience. Groups only differed in time spent actively mouthing objects, with LR infants showing a greater increase in active mouthing than HR infants. Findings suggest that HR infants experience a similar progression of object exploration across sitting development, but on a delayed time scale.

Exploring cortical activation and connectivity in infants with and without familial risk for autism during naturalistic social interactions: A preliminary study

Behavioral signs of Autism Spectrum Disorder (ASD) are typically observable by the second year of life and a reliable diagnosis of ASD is possible by 2 to 3 years of age. Studying infants with familial risk for ASD allows for the investigation of early signs of ASD risk within the first year. Brain abnormalities such as hyper-connectivity within the first year may precede the overt signs of ASD that emerge later in life. In this preliminary study, we use functional near-infrared spectroscopy (fNIRS), an infant-friendly neuroimaging tool that is relatively robust against motion artifacts, to examine functional activation and connectivity during naturalistic social interactions in 9 high-risk (HR; older sibling with ASD) and 6 low-risk (LR; no family history of ASD) infants from 6 to 9 months of age. We obtained two 30-second baseline periods and a 5-minute social interaction period. HR infants showed reduced right and left-hemispheric activation compared to LR infants based on oxy (HbO2) and deoxy (HHb) signal trends. HR infants also had greater functional connectivity than LR infants during the pre- and post-social periods and showed a drop in connectivity during the social period. Our findings are consistent with previous work suggesting early differences in cortical activation associated with familial risk for ASD, and highlight the promise of fNIRS in evaluating potential markers of ASD risk during naturalistic social contexts.

Trajectories of Posture Development in Infants With and Without Familial Risk for Autism Spectrum Disorder.

This study investigated early posture development prospectively in infants at heightened (HR) vs. low risk (Low Risk; LR) for ASD. Fourteen HR infants diagnosed with ASD (HR-ASD), 17 HR infants with language delay (HR-LD), 29 HR infants with no diagnosis (HR-ND), and 25 LR infants were videotaped at home for 25min during everyday activities and play at 6, 8, 10, 12, and 14months. All postures were coded and the sustainment source was identified for supported postures. Relative to LR infants, HR-ASD infants and to a lesser extent HR-LD infants exhibited distinct postural trajectories that revealed slower development of more advanced postures. In addition, subtle differences in posture sustainment differentiated HR-ASD from HR-LD infants.

Early motor abilities in infants at heightened versus low risk for ASD: A Baby Siblings Research Consortium (BSRC) study.

Research has identified early appearing differences in gross and fine motor abilities in infants at heightened risk (HR) for autism spectrum disorder (ASD) because they are the younger siblings of children with ASD, and it suggests that such differences may be especially apparent among those HR infants themselves eventually diagnosed with ASD. The present study examined overall and item-level performance on the gross (GM) and fine motor (FM) subscales of the Mullen Scales of Early Learning (MSEL) administered at 6 months to a large, geographically diverse sample of HR infants with varying developmental outcomes (ASD, elevated ADOS without ASD, low ADOS without ASD) and to infants with low ASD risk (low risk [LR]). We also explored whether motor abilities assessed at 6 months predicted ASD symptom severity at 36 months. FM (but not GM) performance distinguished all 3 HR groups from LR infants with the weakest performance observed in the HR-Elevated ADOS children, who exhibited multiple differences from both LR and other HR infants in both gross and fine motor skills. Finally, 6-month FM (but not GM) scores significant predicted 36-month ADOS severity scores in the HR group; but no evidence was found of specific early appearing motor signs associated with a later ASD diagnosis. Vulnerabilities in infants' fine and gross motor skills may have significant consequences for later development not only in the motor domain but in other domains. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Altered lateralization of dorsal language tracts in 6-week-old infants at risk for autism.

Altered structural connectivity has been identified as a possible biomarker of autism spectrum disorder (ASD) risk in the developing brain. Core features of ASD include impaired social communication and early language delay. Thus, examining white matter tracts associated with language may lend further insight into early signs of ASD risk and the mechanisms that underlie language impairments associated with the disorder. Evidence of altered structural connectivity has previously been detected in 6-month-old infants at high familial risk for developing ASD. However, as language processing begins in utero, differences in structural connectivity between language regions may be present in the early infant brain shortly after birth. Here we investigated key white matter pathways of the dorsal language network in 6-week-old infants at high (HR) and low (LR) risk for ASD to identify atypicalities in structural connectivity that may predict altered developmental trajectories prior to overt language delays and the onset of ASD symptomatology. Compared to HR infants, LR infants showed higher fractional anisotropy (FA) in the left superior longitudinal fasciculus (SLF); in contrast, in the right SLF, HR infants showed higher FA than LR infants. Additionally, HR infants showed more rightward lateralization of the SLF. Across both groups, measures of FA and lateralization of these pathways at 6weeks of age were related to later language development at 18months of age as well as ASD symptomatology at 36months of age. These findings indicate that early differences in the structure of language pathways may provide an early predictor of future language development and ASD risk.

2091 Neurophysiological substrates and developmental sequelae of sensory differences in infants at high risk for autism spectrum disorder

OBJECTIVES/SPECIFIC AIMS: Background: Children with autism spectrum disorder (ASD) show a broad range of unusual responses to sensory stimuli and experiences. It has been hypothesized that early differences in sensory responsiveness arise from atypical neural function and produce “cascading effects” on development across a number of domains, impacting social and communication skill, as well as broader development in children affected by ASD. A primary challenge to confirming these hypotheses is that ASD cannot be definitely diagnosed in the earliest stages of development (i.e., infancy). A potential solution is to prospectively follow infants at heightened risk for ASD based on their status as infant siblings of children who are diagnosed. We examined the developmental sequelae and possible neurophysiological substrates of three different patterns of sensory responsiveness—hyporesponsiveness (reduced or absent responding to sensory stimuli) and hyperresponsiveness (exaggerated responding to sensory stimuli), as well as sensory seeking (craving of or fascination with certain sensory experiences). Infants at high risk (HR) for ASD were compared with a control group of infants at relatively lower risk for ASD (LR; siblings of children with typical developmental histories). Objectives: Research questions included: (a) Do HR infants differ from LR infants in early sensory responsiveness?, (b) Does sensory responsiveness predict future ASD and related symptomatology? and (c) Is sensory responsiveness predicted by resting brain states? METHODS/STUDY POPULATION: Methods: To answer these questions, we carried out a longitudinal correlational investigation in which 20 HR infants and 20 LR controls matched on sex and chronological age were followed over 18 months. At entry to the study, when infants were 18 months old, sensory responsiveness was measured using the Sensory Processing Assessment and the Sensory Experiences Questionnaire, and a number of putative neural signatures of early sensory differences were measured via resting state EEG. When infants were 24 and 36 months of age, ASD and related symptomatology was evaluated in a comprehensive diagnostic evaluation. RESULTS/ANTICIPATED RESULTS: Results: HR infants trended towards increased hyporesponsiveness and hyperresponsiveness and showed significantly elevated levels of sensory seeking relative to LR controls at 18 months of age. Both groups, furthermore, displayed a high degree of heterogeneity in sensory responsiveness. Atypical sensory responsiveness (increased hyperresponsiveness and/or hyporesponsiveness, as well as sensory seeking behavior) predicted several aspects of ASD and related symptomatology, including social, communication, and play skill, and was associated with differences in resting brain state, including metrics of oscillatory power, complexity, and connectivity, as well as hemispheric asymmetry. Moderation analyses revealed that several relations varied according to risk group, such that associations were stronger in magnitude in the HR Versus LR group. DISCUSSION/SIGNIFICANCE OF IMPACT: Conclusion: Findings provide empirical support for the notion that early sensory responsiveness may produce cascading effects on development in infants at heightened risk for ASD. Differences in resting brain states may underlie atypical behavioral patterns of sensory responsiveness. From a clinical standpoint, results suggest that early sensory differences may be useful for predicting developmental trajectories, and be potentially important targets for early preventive intervention, in infants at risk for autism.

Inflexible neurobiological signatures precede atypical development in infants at high risk for autism

Variability in neurobiological signatures is ubiquitous in early life but the link to adverse developmental milestones in humans is unknown. We examined how levels of signal and noise in movement signatures during the 1st year of life constrain early development in 71 healthy typically developing infants, either at High or Low familial Risk (HR or LR, respectively) for developing Autism Spectrum Disorders (ASD). Delays in early learning developmental trajectories in HR infants (validated in an analysis of 1,445 infants from representative infant-sibling studies) were predicted by worse stochastic patterns in their spontaneous head movements as early as 1–2 months after birth, relative to HR infants who showed more rapid developmental progress, as well as relative to all LR infants. While LR 1–2 mo-old infants’ movements were significantly different during a language listening task compared to during sleep, HR infants’ movements were more similar during both conditions, a striking lack of diversity that reveals context-inflexible experience of ambient information. Contrary to expectation, it is not the level of variability per se that is particularly detrimental in early life. Rather, inflexible sensorimotor systems and/or atypical transition between behavioral states may interfere with the establishment of capacity to extract structure and important cues from sensory input at birth, preceding and contributing to an atypical brain developmental trajectory in toddlerhood.

Response to changing contingencies in infants at high and low risk for autism spectrum disorder.

One recently proposed theory of autism spectrum disorder (ASD) hypothesizes that individuals with the disorder may have difficulty using prior experiences to predict future events [Hellendoorn et al., 2015; Northrup, 2016; Sinha et al., 2014]. To date, this theory has not been tested in infancy. The current study analyzed how young infants at heightened (HR; older sibling with ASD) vs. low risk (LR; no first degree relatives with ASD) for ASD responded to changing contingencies when interacting with two visually identical rattles-one that produced sounds during shaking (Sound), and one that did not (Silent). Infants were given the rattles in a Sound-Silent-Sound order at 6 and 10 months, and shaking behavior was coded. Results indicated that LR and HR infants (regardless of ASD diagnosis) did not differ from each other in shaking behavior at 6 months. However, by 10 months, LR infants demonstrated high initial shaking with all three rattles, indicating expectations for rattle affordances, while HR infants did not. Significantly, HR infants, and particularly those with an eventual ASD diagnosis, did not demonstrate an "extinction burst"-or high level of shaking-in the first 10 sec with the "silent" rattle, indicating that they may have difficulty generalizing learning from one interaction to the next. Further, individual differences in the strength of this "extinction burst" predicted cognitive development in toddlerhood among HR infants. Difficulty forming expectations for new interactions based on previous experiences could impact learning and behavior in a number of domains. Autism Res 2017. © 2017 International Society for Autism Research, Wiley Periodicals, Inc. Autism Res 2017, 10: 1239-1248. © 2017 International Society for Autism Research, Wiley Periodicals, Inc.

Emerging Executive Functioning and Motor Development in Infants at High and Low Risk for Autism Spectrum Disorder.

Existing evidence suggests executive functioning (EF) deficits may be present in children with autism spectrum disorder (ASD) by 3 years of age. It is less clear when, prior to 3 years, EF deficits may emerge and how EF unfold over time. The contribution of motor skill difficulties to poorer EF in children with ASD has not been systematically studied. We investigated the developmental trajectory of EF in infants at high and low familial risk for ASD (HR and LR) and the potential associations between motor skills, diagnostic group, and EF performance. Participants included 186 HR and 76 LR infants. EF (A-not-B), motor skills (Fine and Gross Motor), and cognitive ability were directly assessed at 12 months and 24 months of age. Participants were directly evaluated for ASD at 24 months using DSM-IV-TR criteria and categorized as HR-ASD, HR-Negative, and LR-Negative. HR-ASD and HR-Negative siblings demonstrated less improvement in EF over time compared to the LR-Negative group. Motor skills were associated with group and EF performance at 12 months. No group differences were found at 12 months, but at 24 months, the HR-ASD and HR-Negative groups performed worse than the LR-Negative group overall after controlling for visual reception and maternal education. On reversal trials, the HR-ASD group performed worse than the LR-Negative group. Motor skills were associated with group and EF performance on reversal trials at 24 months. Findings suggest that HR siblings demonstrate altered EF development and that motor skills may play an important role in this process.

Atypical processing of voice sounds in infants at risk for autism spectrum disorder

Adults diagnosed with autism spectrum disorder (ASD) show a reduced sensitivity (degree of selective response) to social stimuli such as human voices. In order to determine whether this reduced sensitivity is a consequence of years of poor social interaction and communication or is present prior to significant experience, we used functional MRI to examine cortical sensitivity to auditory stimuli in infants at high familial risk for later emerging ASD (HR group, N = 15), and compared this to infants with no family history of ASD (LR group, N = 18). The infants (aged between 4 and 7 months) were presented with voice and environmental sounds while asleep in the scanner and their behaviour was also examined in the context of observed parent–infant interaction. Whereas LR infants showed early specialisation for human voice processing in right temporal and medial frontal regions, the HR infants did not. Similarly, LR infants showed stronger sensitivity than HR infants to sad vocalisations in the right fusiform gyrus and left hippocampus. Also, in the HR group only, there was an association between each infant's degree of engagement during social interaction and the degree of voice sensitivity in key cortical regions. These results suggest that at least some infants at high-risk for ASD have atypical neural responses to human voice with and without emotional valence. Further exploration of the relationship between behaviour during social interaction and voice processing may help better understand the mechanisms that lead to different outcomes in at risk populations.

Shorter spontaneous fixation durations in infants with later emerging autism

Little is known about how spontaneous attentional deployment differs on a millisecond-level scale in the early development of autism spectrum disorders (ASD). We measured fine-grained eye movement patterns in 6-to 9-month-old infants at high or low familial risk (HR/LR) of ASD while they viewed static images. We observed shorter fixation durations (i.e. the time interval between saccades) in HR than LR infants. Preliminary analyses indicate that these results were replicated in a second cohort of infants. Fixation durations were shortest in those infants who went on to receive an ASD diagnosis at 36 months. While these findings demonstrate early-developing atypicality in fine-grained measures of attentional deployment early in the etiology of ASD, the specificity of these effects to ASD remains to be determined.

Emerging cognitive profiles in high-risk infants with and without autism spectrum disorder

This paper examined early developmental trajectories in a large, longitudinal sample at high-risk for ASD (‘HR’) and low-risk (‘LR’) controls, and the association of trajectories with 3-year diagnosis. Developmental assessments were conducted at 6, 12, 24 months, and 3 years, with blinded “clinical best-estimate” expert diagnosis at age 3. HR infants were enrolled based only on familial risk. LR infants, from community sources, had no first- or second-degree ASD relatives. All infants were born at 36–42 weeks, weighing ≥2500g, with no identifiable neurological, genetic, or severe sensory/motor disorders. Analytic phase I: semi-parametric group-based modeling to identify distinct developmental trajectories (n=680; 487 HR; 193 LR); phase II: Trajectory membership in relation to 3-year diagnosis (n=424; 310 HR; 114 LR). Three distinct trajectories emerged (1) inclining; (2) stable-average; (3) declining; trajectory membership predicted diagnosis (χ2=99.40; p<.001). Most ASD cases were in stable-average (50.6%) or declining trajectories (33.8%); most non-ASD-HR infants were in inclining (51.9%) or stable-average (40.3%) trajectories. The majority of LR controls were in the inclining trajectory (78.9%). Within the declining trajectory, over half had ASD (57.8%), but 40% were non-ASD-HR infants. Declining/plateauing raw scores were associated with, but not exclusive to, ASD. Findings underscore the importance of monitoring the emergence of ASD symptoms and overall development in high-risk children. Evidence of developmental slowing or decline may be associated not only with ASD, but with other suboptimal outcomes, warranting careful clinical follow-up.

Intestinal permeability as measured by lactulose mannitol ratio continues to decrease during infancy after 3 months of age for both control infants and infants at high risk for autism spectrum disorders (LB751)

Approximately 40% of individuals with autism spectrum disorder (ASD) have hyperpermeable intestines as measured by lactulose/mannitol absorption ratio. This could be the cause or symptom of the gastrointestinal co‐morbidity associated with ASD. It is not known if this increased permeability is present prior to ASD diagnosis. The objective of this study was to determine intestinal permeability in both infants at high‐risk (HR) of developing ASD (due to having an older sibling with ASD their risk of developing ASD is increased from ~0.9% to ~20%) and in low‐risk (LR, no family history) controls, given that no studies of intestinal permeability have been done in infants greater than approximately 3 months of age. Using a commercial assay we measured lactulose/mannitol absorption ratio (L/M) in infants ranging from 3 months to 36 months of age (the majority less than 15 months) and determined their diet at the time by parental questionnaire. We observed a negative correlation between L/M and age (HR: ‐0.39, LR: ‐0.34) and a significantly higher L/M in infants between 3 and 7 months of age versus infants greater than 7 months for both HR and LR infants. Interestingly, HR infants had significantly lower L/M than LR infants, an effect that appeared to be driven by a significantly higher permeability in LR infants on a mixed diet of breast milk and other foods compared to HR infants on a mixed diet or LR infants on a no breast milk diet. Only one HR infant demonstrated hyperpermeability. These results suggest that intestinal permeability continues to decrease even after 3 months as part of typical development and that hyperpermeability is a later event in ASD and may not appear in the first year of life.Grant Funding Source: NIH NS071580 and GM85072

Posture Development in Infants at Heightened vs. Low Risk for Autism Spectrum Disorders.

Evidence suggests that children and adults diagnosed with autism spectrum disorders (ASD) exhibit difficulties with postural control. Retrospective video studies of infants later diagnosed with ASD indicate that infants who eventually receive an ASD diagnosis exhibit delays in postural development. This study investigates early posture development prospectively and longitudinally in 22 infants at heightened biological risk for ASD (HR) and 18 infants with no such risk (Low Risk; LR). Four HR infants received an autism diagnosis (AD infants) at 36 months. Infants were videotaped at home at 6, 9, 12, and 14 months during everyday activities and play. All infant postures were coded and classified as to whether or not they were infant-initiated. Relative to LR infants, HR infants were slower to develop skill in sitting and standing postures. AD infants exhibited substantial delays in the emergence of more advanced postures and initiated fewer posture changes. Because posture advances create opportunities for infants to interact with objects and people in new and progressively more sophisticated ways, postural delays may have cascading effects on opportunities for infant exploration and learning. These effects may be greater for infants with ASD, for whom posture delays are more significant.

Relation between early motor delay and later communication delay in infants at risk for autism

BackgroundMotor delays have been reported in retrospective studies of young infants who later develop Autism Spectrum Disorders (ASDs). ObjectiveIn this study, we prospectively compared the gross motor development of a cohort at risk for ASDs; infant siblings of children with ASDs (AU sibs) to low risk typically developing (LR) infants. Methods24 AU sibs and 24 LR infants were observed at 3 and 6 months using a standardized motor measure, the Alberta Infant Motor Scale (AIMS). In addition, as part of a larger study, the AU sibs also received a follow-up assessment to determine motor and communication performance at 18 months using the Mullen Scales of Early Learning. ResultsSignificantly more AU sibs showed motor delays at 3 and 6 months than LR infants. The majority of the AU sibs showed both early motor delays and later communication delays. LimitationsSmall sample size and limited follow-up. ConclusionsEarly motor delays are more common in AU sibs than LR infants. Communication delays later emerged in 67–73% of the AU sibs who had presented with early motor delays. Overall, early motor delays may be predictive of future communication delays in children at risk for autism.

From biological rhythms to social rhythms: Physiological precursors of mother-infant synchrony.

Links between neonatal biological rhythms and the emergence of interaction rhythms were examined in 3 groups (N = 71): high-risk preterms (HR; birth weight <1,000 g), low-risk preterms (LR; birth weight =1,700-1,850 g), and full-term (FT) infants. Once a week for premature infants and on the 2nd day for FT infants, sleep-wake cyclicity was extracted from 4-hr observations and cardiac vagal tone was measured. At term age, infant orientation was tested with the Neonatal Behavior Assessment Scale. At 3 months, arousal modulation and emotion regulation were assessed, and mother-infant synchrony was computed from microanalysis of face-to-face interactions using time-series analysis. Sleep-wake amplitudes showed a developmental leap at 31 weeks gestation, followed by a shift in vagal tone at 34 weeks gestation. At term, differences among FT, LR, and HR infants were observed for biological rhythms in a linear-decline pattern. Sleep-wake cyclicity, vagal tone, newborn orientation, and arousal modulation were each uniquely predictive of mother-infant synchrony. The organization of physiological oscillators appears to lay the foundation for the infant's capacity to partake in a temporally matched social dialogue.