Infants Born Preterm Demonstrate Impaired Exploration of Their Bodies and Surfaces Throughout the First 2 Years of Life

Correlation between pose estimation features regarding movements towards the midline in early infancy

In infants, spontaneous movement towards the midline (MTM) indicates the initiation of anti-gravity ability development. Markerless 2D pose estimation is a cost-effective, time-efficient, and quantifiable alternative to movement assessment. We aimed to establish correlations between pose estimation features and MTM in early-age infants. Ninety-four infant videos were analysed to calculate the percentage and rate of MTM occurrence. 2D Pose estimation processed the videos and determined the distances and areas using wrist and ankle landmark coordinates. We collected data using video recordings from 20 infants aged 8-16 weeks post-term age. Correlations between MTM observations and distance values were evaluated. Differences in areas between groups of videos showing MTM and no MTM in the total, lower-limb, and upper-limb categories were examined. MTM observations revealed common occurrences of hand-to-trunk and foot-to-foot movements. Weak correlations were noted between limb distances to the midbody imaginary line and MTM occurrence values. Lower MTM showed significant differences in the lower part (p = 0.003) and whole area (p = 0.001). Video recording by parents or guardians could extract features using 2D pose estimation, assisting in the early identification of MTM in infants. Further research is required to assess a larger sample size with the diversity of MTM motor behaviour, and later developmental skills, and collect data from at-risk infants.

Biological and environmental factors may affect children's executive function through motor and sensorimotor development: Preterm birth and cerebral palsy

Disruptive biological and environmental factors may undermine the development of children's motor and sensorimotor skills. Since the development of cognitive skills, including executive function, is grounded in early motor and sensorimotor experiences, early delays or impairments in motor and sensorimotor processing often trigger dynamic developmental cascades that lead to suboptimal executive function outcomes. The purpose of this perspective paper is to link early differences in motor/sensorimotor processing to the development of executive function in children born preterm or with cerebral palsy. Uncovering such links in clinical populations would improve our understanding of developmental pathways and key motor and sensorimotor skills that are antecedent and foundational for the development of executive function. This knowledge will allow the refinement of early interventions targeting motor and sensorimotor skills with the goal of proactively improving executive function outcomes in at-risk populations.

A Comparison of the Clinical Presentation of Preterm Birth and Autism Spectrum Disorder: Commonalities and Distinctions in Children Under 3

Premature infants and infants later diagnosed with autism spectrum disorder (ASD) share many commonalities in clinical presentations. However, prematurity and ASD also have differences in clinical presentation. These overlapping phenotypes can lead to misdiagnoses of ASD or missing a diagnosis of ASD in preterm infants. We document these commonalities and differences in various developmental domains with the hope of aiding in the accurate early detection of ASD and timely intervention implementation in children born premature. Given the degree of similarities in presentation, evidence-based interventions designed specifically for preterm toddlers or toddlers with ASD may ultimately aid both populations.

Relationship between fidgety movement and frequency of movement toward midline: An observational study

BACKGROUND

Infants show other movements and posture patterns during the fidgety movement period, including movement toward midline (MTM). Few studies have quantified MTM occurring during the fidgety movement period.

AIMS

This study aimed to examine the relationship between fidgety movements (FMs) and MTM frequency and occurrence rate per minute, from two video data sets (video attached to Prechtl video manual and accuracy data from Japan).

STUDY DESIGN

Observational study.

SUBJECTS

It encompassed 47 videos. Of these, 32 were deemed normal FMs. The study amalgamated FMs that were sporadic, abnormal, or absent into a category of aberrant (n = 15).

OUTCOME MEASURES

Infant video data were observed. MTM item occurrences were recorded and calculated for occurrence percentage and MTM rate of occurrence per minute. The differences between groups for the upper limbs, lower limbs, and total MTM were statistically analysed.

RESULTS

Twenty-three infant videos of normal FMs and seven infant videos of aberrant FMs showed MTM. Eight infant videos of aberrant FMs showed no MTM, and only four with absent FMs were included. There was a significant difference in the total MTM rate of occurrence per minute between normal FMs versus aberrant FMs (p = 0.008).

CONCLUSIONS

This study presented MTM frequency and rate of occurrence per minute in infants who showed FMs during the fidgety movement period. Those who showed absent FMs also demonstrated no MTM. Further study may need a larger sample size of absent FMs and information on later development.

Infants born preterm demonstrate reduced task-specific exploration during the scaffolded kick-activated mobile task

This study quantified the spatial exploration of 13 infants born very and extremely preterm (PT) at 4 months corrected age as they learned that moving their feet vertically to cross a virtual threshold activated an infant kick-activated mobile and compared results to 15 infants born full-term (FT) from a previously published study. Spatial exploration was quantified using two general spatial exploration variables (exploration volume, exploration path), two task-specific spatial variables (duration of time in the task-specific region of interest, vertical variance of kicks), and one non-task-specific spatial variable (horizontal variance of kicks). The infants born PT, similar to FT, increased their general spatial exploration and duration in the region of interest and did not change the vertical and horizontal variances of kicks. However, the infants born PT, compared to FT, spent less time in the task-specific region of interest and had a greater non-task-specific horizontal variance throughout the task. This may indicate that infants born PT and FT exhibit similar general spatial exploration, but infants born PT exhibit less task-specific spatial exploration. Future research is necessary to determine the contribution of learning and motor abilities to the differences in task-specific exploration between infants born PT and FT.

A model for using developmental science to create effective early intervention programs and technologies to improve children's developmental outcomes

Children born with a variety of environmental or medical risk factors may exhibit delays in global development. Very often, such delays are identified at preschool or school age, when children are severely overdue for effective early interventions that can alleviate the delays. This chapter proposes a conceptual model of child development to inform the creation of interventions and rehabilitative technologies that can be provided very early in development, throughout the first year of life, to optimize children's future developmental outcomes. The model suggests that early sensorimotor skills are antecedent and foundational for future motor, cognitive, language, and social development. As an example, this chapter describes how children's early postural control and exploratory movements facilitate the development of future object exploration behaviors that provide enhanced opportunities for learning and advance children's motor, cognitive, language, and social development. An understanding of the developmental pathways in the model can enable the design of effective intervention programs and rehabilitative technologies that target sensorimotor skills in the first year of life with the goal of minimizing or ameliorating the delays that are typically identified at preschool or school age. Specific examples of early interventions and rehabilitative technologies that have effectively advanced children's motor and cognitive development by targeting early sensorimotor skills and behaviors are provided.

From Hemispheric Asymmetry through Sensorimotor Experiences to Cognitive Outcomes in Children with Cerebral Palsy

Recent neuroimaging studies allowed us to explore abnormal brain structures and interhemispheric connectivity in children with cerebral palsy (CP). Behavioral researchers have long reported that children with CP exhibit suboptimal performance in different cognitive domains (e.g., receptive and expressive language skills, reading, mental imagery, spatial processing, subitizing, math, and executive functions). However, there has been very limited cross-domain research involving these two areas of scientific inquiry. To stimulate such research, this perspective paper proposes some possible neurological mechanisms involved in the cognitive delays and impairments in children with CP. Additionally, the paper examines the ways motor and sensorimotor experience during the development of these neural substrates could enable more optimal development for children with CP. Understanding these developmental mechanisms could guide more effective interventions to promote the development of both sensorimotor and cognitive skills in children with CP.

Development of the Ontogenetic Self-Regulation Clock

To date, there is no overarching proposition for the ontogenetic-neurobiological basis of self-regulation. This paper suggests that the balanced self-regulatory reaction of the fetus, newborn and infant is based on a complex mechanism starting from early brainstem development and continuing to progressive control of the cortex over the brainstem. It is suggested that this balance occurs through the synchronous reactivity between the sympathetic and parasympathetic systems, both which originate from the brainstem. The paper presents an evidence-based approach in which molecular excitation-inhibition balance, interchanges between excitatory and inhibitory roles of neurotransmitters as well as cardiovascular and white matter development across gestational ages, are shown to create sympathetic-parasympathetic synchrony, including the postnatal development of electroencephalogram waves and vagal tone. These occur in developmental milestones detectable in the same time windows (sensitive periods of development) within a convergent systematic progress. This ontogenetic stepwise process is termed "the self-regulation clock" and suggest that this clock is located in the largest connection between the brainstem and the cortex, the corticospinal tract. This novel evidence-based new theory paves the way towards more accurate hypotheses and complex studies of self-regulation and its biological basis, as well as pointing to time windows for interventions in preterm infants. The paper also describes the developing indirect signaling between the suprachiasmatic nucleus and the corticospinal tract. Finally, the paper proposes novel hypotheses for molecular, structural and functional investigation of the "clock" circuitry, including its associations with other biological clocks. This complex circuitry is suggested to be responsible for the developing self-regulatory functions and their neurobehavioral correlates.

Inter- and Intra-rater Reliability of the Head Control Scale: Brief Report

PURPOSE

To examine inter-rater and intra-rater reliability of the Head Control Scale (HCS).

METHODS

Introduction of the HCS to eight physical therapists in a pediatric post-acute hospital was followed by use in a repeated-measures design across two trials to establish reliability of the raters. Therapists scored the HCS twice within 4 weeks, using videos of infants at both 2 and 6 months of age, one infant described as typically developing and one with atypical development.

RESULTS

For the HCS overall score, reliability was excellent with an inter-rater reliability intraclass correlation coefficient ((ICC) (3,1) = 0.97 (95% confidence interval, 0.899-0.998) and intra-rater reliability ICC (3,1) range = 0.815-1.0. HCS position scores between and within raters ranged from slight to substantial agreement.

CONCLUSION

In this small study of inter- and intra-rater reliability, HCS overall score demonstrated excellent reliability for all raters however, HCS position scores demonstrated some variability, especially for the prone position.

Prevailing head position to one side in early infancy-A population-based study

AIM

To determine the prevalence of prevailing head position to one side (PHP) in young infants and to evaluate its associations with reaching performance, neurological condition and perinatal and socio-economic factors.

METHODS

Observational study in 500 infants (273 boys) 2-6 months corrected age, representative of the Dutch population (median gestational age 39.7 weeks (27-42); birthweight 3438 g (1120-4950). Prevailing head position to one side and reaching performance were assessed with the Infant Motor Profile; neurological condition with the Standardized Infant NeuroDevelopmental Assessment. Socio-economic information and perinatal information were obtained by questionnaire and medical records. Associations were analysed with uni- and multivariable statistics.

RESULTS

Prevailing head position to one side was observed in 100 infants (20%), and its prevalence decreased from 49% at 2 months to 0% at 6 months. Only in infants aged 4-5 months PHP was significantly associated with worse reaching and an at-risk neurological score. Prevailing head position to one side was weakly associated with prenatal substance exposure, post-natal admission to a paediatric ward and paternal native Dutch background.

CONCLUSION

Prevailing head position to one side at 2-3 months is a frequently occurring sign with limited clinical significance. Yet, PHP at 4-5 months is associated with a worse functional and neurological condition. Therefore, PHP at 4-5 months could serve as a red flag indicating possible challenges in later development.

Early neurodevelopmental outcome in preterm posthemorrhagic ventricular dilatation and hydrocephalus: Neonatal ICU Network Neurobehavioral Scale and imaging predict 3-6-month motor quotients and Capute Scales

OBJECTIVE

Brain injury remains a serious complication of prematurity. Almost half of infants with severe intraventricular hemorrhage (IVH) develop posthemorrhagic ventricular dilatation (PHVD) and 20% need surgery for posthemorrhagic hydrocephalus (PHH). This population is associated with an increased risk of later neurodevelopmental disability, but there is uncertainty about which radiological and examination features predict later disability. In this study the authors sought to devise and describe a novel combination of neurobehavioral examination and imaging for prediction of neurodevelopmental disability among preterm infants with PHVD and PHH.

METHODS

The study patients were preterm infants (< 36 weeks gestation) with IVH and PHVD, with or without PHH. Ventricular index (VI), anterior horn width (AHW), thalamooccipital distance (TOD), ventricle/brain (V/B) ratio, and resistive indices (RIs) were recorded on the head ultrasound (HUS) just prior to surgery, or the HUS capturing the worst PHVD when surgery was not indicated. The posterior fossa was assessed with MRI. Neonatal ICU Network Neurobehavioral Scale (NNNS) examinations were performed at term age equivalent for each infant. A neurodevelopmental assessment using the Capute Scales (Capute Cognitive Adaptive Test [CAT] scores and Capute Clinical Linguistic Auditory Milestone Scale [CLAMS] scores) and a motor quotient (MQ) assessment were performed between 3 and 6 months of age corrected for degree of prematurity (corrected age). MQs < 50 reflect moderate to severe delays in early motor milestone attainment, CAT scores < 85 reflect delays in early visual and problem-solving abilities, and CLAMS scores < 85 reflect delays in early language.

RESULTS

Twenty-one infants underwent assessments that included imaging and NNNS examinations, Capute Scales assessments, and MQs. NNNS nonoptimal reflexes (NOR) and hypertonicity subscores and AHW were associated with MQs < 50: NOR subscore OR 2.46 (95% CI 1.15-37.6, p = 0.034), hypertonicity subscore OR 1.68 (95% CI 1.04-3.78, p = 0.037), and AHW OR 1.13 (95% CI 1.01-1.39, p = 0.041). PVHI, cystic changes, and neurosurgical intervention were associated with CAT scores < 85: PVHI OR 9.2 (95% CI 1.2-73.2, p = 0.037); cystic changes OR 12.0 (95% CI 1.0-141.3, p = 0.048), and neurosurgical intervention OR 11.2 (95% CI 1.0-120.4, p = 0.046). Every 1-SD increase in the NOR subscore was associated with an increase in odds of a CAT score < 85, OR 4.0 (95% CI 1.0-15.0, p = 0.044). Worse NNNS NOR subscores were associated with early language delay: for a 1-SD increase in NOR subscore, there was an increase in the odds of a CLAMS score < 85, OR 19.5 (95% CI 1.3-303, p = 0.034).

CONCLUSIONS

In former preterm children with severe IVH and PHVD, neonatal neurological examination findings and imaging features are associated with delays at 3-6 months in motor milestones, visual and problem-solving abilities, and language.

The shape of disposable diaper affects spontaneous movements of lower limbs in young infants

This study examined the characteristics of young infants' lower limb spontaneous movements based on differences in shape of diapers. Twenty-seven healthy infants (103 ± 16.3 days old) were enrolled in this study. We measured the spontaneous movements of their lower limbs in four conditions (Naked, wearing Normal type diapers, wearing Type A diapers, and wearing Type B diapers). The Normal diaper has a wider waist belt than the Type A diaper, and the Type B diaper has a narrower crotch area than the Type A diaper. We observed them in seven indices (the velocity of lower limb movements, the trajectory area of knee movement in the sagittal plane and the frontal plane, the distance between both knees and between side of abdomen and knee, and correlation of velocities between side of abdomen and knee and between left and right ankles). The results showed that the velocity of the lower limb movements in the Naked condition was higher than when wearing Normal diapers. The value for the trajectory area of knee movement in sagittal plane, which reflects the range of lower leg lifting movements and closeness of such movements to the trunk, for the Type B diaper condition was higher than that for the Normal diaper condition. This result indicates that the shape of the diaper affects the spontaneous movements of the lower limbs of young infants.

Increasing task precision demands reveals that the reach and grasp remain subject to different perception-action constraints in 12-month-old human infants

The reach and grasp follow different developmental trajectories, but are often considered to have achieved nearly adult-like precision and integration by 12 months of age. This study used frame-by-frame video analysis to investigate whether increasing precision demands, by placing small reaching targets on a narrow pedestal rather than on a flat table, would influence the reach and grasp movements of 12-month-old infants in a complementary or differential fashion. The results reveal that placing the target atop a pedestal impaired the infants's ability to direct an appropriate digit towards the small target, but did not produce a corresponding decrease in the frequency with which they used an index-thumb pincer grip to grasp the target. This was due to the fact that, although infants were more likely to contact the target with a suboptimal part of the hand in the pedestal condition, a greater proportion of these suboptimal contacts ultimately transitioned to a successful index-thumb pincer grip. Thus, increasing task precision demands impaired reach accuracy, but facilitated index-thumb grip formation, in 12-month-old infants. The differential response of the reach and grasp to the increased precision demands of the pedestal condition suggests that the two movements are not fully integrated and, when precision demands are great, remain sensitive to different perception-action constraints in 12-month-old infants.

Sitting Matters! Differences Between Sitters and Nonsitters at 6 Months' Adjusted Age in Infants At-Risk and Born Preterm

PURPOSE

Sitting delays in infants born preterm compound cognitive and language deficits. This retrospective study examines differences in prematurity-related risk and compares developmental outcomes between sitters and nonsitters at 6 months' adjusted age.

METHODS

A total of 105 graduates of the neonatal intensive care unit met inclusion criteria. Infant demographic and medical risk profiles and 6-month Bayley Scales of Infant Development-3rd edition (BSID-III) cognitive and language scores were retrieved. Infants who sat with hands free greater than 60 seconds were classified as "sitters."

RESULTS

Sixty-nine percent of the sample were nonsitters and were born earlier, had lower birth weights, were chronologically older at follow-up, and spent more days with respiratory support. BSID-III scores were significantly higher in sitters but did not differ by gender, multiple birth, head ultrasound results, payment type, or race/ethnicity.

CONCLUSION

Sitting abilities at 6 months' adjusted age are associated with prematurity risk factors. Cognitive and language scores differ significantly between sitters and nonsitters.

Sit Still and Pay Attention! Trunk Movement and Attentional Resources in Infants with Typical and Delayed Development

AIMS

(1) examine infant movement during an early posture (sitting) utilizing a novel video assessment technique; and (2) document the differences between infants with typical development (TD), premature infants with motor delay, and infants with cerebral palsy (CP) during focused and nonfocused attention (NFA).

METHODS

Infants were tested when they began to sit independently. We utilized Eulerian Video Magnification (EVM) to accentuate small trunk and pelvic movements for visual coding from video taken during a natural play task with and without focused attention (FA).

RESULTS

Trunk/pelvic movement varied as a function of both motor skill and attention. Infants with TD and CP made fewer trunk movements during periods of FA than NFA. Preterm infants exhibited more trunk/pelvic movement than the other groups and their movement did not differ based on attention type.

CONCLUSIONS

The EVM technique allowed for replicable coding of real-time "hidden" motor adjustments from video. The capacity to minimize extraneous movements in infants, or "sitting still" may allow greater attention to the task at hand, similar to older children and adults. Premature infants' excessive trunk/pelvic movement that did not adapt to task requirements could, in the long term, impact tasks requiring attentional resources.

Therapy services and specialized devices for conjoined twins: Unique challenges with conjoined twins and the importance of physical and occupational therapy

Conjoined twins are a rare occurrence that offer unique challenges and circumstances to therapists. The overall goal of physical and occupational therapy treatment is to provide care that promotes developmental progression to two conjoined individuals with distinct personalities and potentially different physical and medical needs. The unique presentation of conjoined twins must be considered in determining therapeutic goals, interventions and plans of care. Providing therapeutic interventions throughout the NICU stay is a dynamic, evolving process, which challenges the therapy team to work together to find solutions. This paper aims to highlight the considerations, challenges, and strategies used to address barriers in the therapeutic care of conjoined twins.

Prematurity may negatively impact means-end problem solving across the first two years of life

Preterm infants are at risk for delays in motor, perceptual, and cognitive development. While research has shown preterm infants may exhibit learning delays in the first months of life, these delays are commonly under-diagnosed. The purpose of this study was to longitudinally evaluate behavioral performance and learning in two means-end problem-solving tasks for 30 infants born preterm (PT) and 23 born full-term (FT). Infants were assessed at 6, 9, 12, 18, and 24 months-old in tasks that required towel pulling or turntable rotation to obtain a distant object. PT infants performed more non-goal-directed and less goal-directed behavior than FT infants throughout the study, resulting in a lower success rate among PT infants. PT infants showed delayed emergence of intentionality (prevalence of goal-directed behaviors) compared to FT infants in both tasks. Amount and variability of behavioral performance significantly correlated with task success differentially across age. The learning differences documented between PT and FT infants suggest means-end problem-solving tasks may be useful for the early detection of learning delays. The identification of behaviors associated with learning and success across age may be used to guide interventions aimed at advancing early learning for infants at risk.

Touch the table before the target: contact with an underlying surface may assist the development of precise visually controlled reach and grasp movements in human infants

Multiple motor channel theory posits that skilled hand movements arise from the coordinated activation of separable neural circuits in parietofrontal cortex, each of which produces a distinct movement and responds to different sensory inputs. Prehension, the act of reaching to grasp an object, consists of at least two movements: a reach movement that transports the hand to a target location and a grasp movement that shapes and closes the hand for target acquisition. During early development, discrete pre-reach and pre-grasp movements are refined based on proprioceptive and tactile feedback, but are gradually coordinated together into a singular hand preshaping movement under feedforward visual control. The neural and behavioural factors that enable this transition are currently unknown. In an attempt to identify such factors, the present descriptive study used frame-by-frame video analysis to examine 9-, 12-, and 15-month-old infants, along with sighted and unsighted adults, as they reached to grasp small ring-shaped pieces of cereal (Cheerios) resting on a table. Compared to sighted adults, infants and unsighted adults were more likely to make initial contact with the underlying table before they contacted the target. The way in which they did so was also similar in that they generally contacted the table with the tip of the thumb and/or pinky finger, a relatively open hand, and poor reach accuracy. Despite this, infants were similar to sighted adults in that they tended to use a pincer digit, defined as the tip of the thumb or index finger, to subsequently contact the target. Only in infants was this ability related to their having made prior contact with the underlying table. The results are discussed in relation to the idea that initial contact with an underlying table or surface may assist infants in learning to use feedforward visual control to direct their digits towards a precise visual target.