Early human motor development: From variation to the ability to vary and adapt

Early gross motor performance is associated with concurrent prelinguistic and social development

BACKGROUND

To study how early gross motor development links to concurrent prelinguistic and social development.

METHODS

We recruited a population-based longitudinal sample of 107 infants between 6 and 21 months of age. Gross motor performance was quantified using novel wearable technology for at-home recordings of infants' spontaneous activity. The infants' prelinguistic and social development was assessed in parallel with a standardized parental questionnaire (Infant Toddler Checklist). The developmental trajectories of motor, prelinguistic, and social performance were inspected longitudinally at individual level, and correlated to each other to measure the relative, age-adjusted advance in performance (z-scores).

RESULTS

Advanced gross motor maturation (higher z-score) links to more advanced prelinguistic development (β = 0.033, p = 0.016, R2 = 0.706) and social development (β = 0.038, p = 0.025, R2 = 0.600). When looking at specific gross motor skills, an increased amount of independent movement (crawling, standing, walking) links to more advanced prelinguistic and social abilities.

CONCLUSION

We introduce a novel approach that measures individual level gross motor development longitudinally at high resolution from child's spontaneous movements at home. This approach shows that age-adjusted relative advance in motor performance is linked to concurrent prelinguistic and social development, supporting the idea of developmental interaction across neurocognitive domains.

IMPACT

Early gross motor, prelinguistic, and social developments show trackable idiosyncratic trajectories. Maturity in gross motor performance links to concurrent prelinguistic and social development. Gross motor performance can be assessed reliably and objectively from infants' spontaneous activity using unsupervised wearable recordings in their native environment, the homes. The present methodology with longitudinal quantitative assessments and age-adjusted modeling with z-scores introduce a potential paradigm shift to studying early neurodevelopment in the context of pediatric health, benchmarking of therapeutic interventions, and other developmental studies.

Sex Differences in the Striatal Contributions to Longitudinal Fine Motor Development in Autistic Children

BACKGROUND

Fine motor challenges are prevalent in autistic populations. However, little is known about their neurobiological underpinnings or how their related neural mechanisms are influenced by sex. The dorsal striatum, comprised of the caudate nucleus and putamen, is associated with motor learning and control and may hold critical information. We investigated how autism diagnosis and sex assigned at birth influence associations between the dorsal striatum and fine motor development in autistic and non-autistic children.

METHODS

We used multimodal assessment of striatal structures (volume and cortico-striatal white matter microstructure) and longitudinal assessment of fine motor skills, first at approximately 3 years of age (Time 1) and again 2-3 years later (Follow-up). Fine motor and magnetic resonance imaging (T1 and diffusion) data were collected at Time 1 from 356 children (234 autistic; 128 female) and at Follow-up from 195 children (113 autistic; 76 female).

RESULTS

At Time 1, associations among fine motor skills, putamen volume, and sensorimotor-striatal fractional anisotropy (sensorimotor-affiliated dorsal striatal structures) were different in autistic boys compared to autistic girls and were not significant for non-autistic children. Further, Time 1 sensorimotor-striatal and prefrontal-striatal microstructure predicted fine motor development for autistic girls but not boys.

CONCLUSIONS

Sensorimotor-affiliated dorsal striatum structures may contribute to concurrent motor ability and predict fine motor improvement during critical windows of development in a sex-specific and diagnosis-dependent way. Moreover, the dorsal striatum may play a key role in the distinct neural mechanisms underlying motor challenges in autistic males and females.

The importance of trunk motion in wearable based infant spontaneous movement analysis

The characteristics of spontaneous movements in infants are essential for the early detection of neurological pathologies, with the Prechtl method being a widely recognized approach. While the Prechtl method is effective in predicting motor risks, its reliance on the evaluator's expertise limits its scalability, particularly in low-income areas. In such contexts, the use of inertial sensors combined with automated analysis presents a promising accessible alternative; however, more research is necessary to get results comparable to those of the Precht method. This research aims to determine the more important metrics of trunk and limbs to assess spontaneous movement in healthy infants during the first semester of life as the basis of a sensor-based alternative. It was a cross-sectional study with 116 separate subjects divided into 3 groups: 0 M Group (N = 43), 3 M Group (N = 44), and 6 M (N = 29). Participants' movements were recorded using 6 wireless inertial sensors (4 limbs, thorax, and pelvis). Parameters from the acceleration signal were estimated in relation to velocity, cross-correlation, kurtosis, skewness, area, and periodicity. The different stages (0 M,3 M, and 6 M) have different profiles of accelerometric parameters. Trunk and limb parameters can differentiate between 0 of 3 months (13/25 trunk and 17/36 limb parameters) and between 0 and 6 months (10/25 trunk and 20/36 limb). Mainly, trunk parameters can differentiate between 3 and 6 months (9/25 trunk vs. 3/36 limb). Additionally, only 2 trunk parameters (kurtosis and periodicity) can differentiate the 3 stages. Wearable devices can effectively detect significant differences in spontaneous movements during the first six months of life, particularly trunk-related data. The extremities could be insufficient to distinguish movements between 3 and 6 months. On the other hand, two key parameters-kurtosis of thorax velocity and periodicity of trunk velocity-successfully differentiate between the three age groups analyzed.

A multi-level analysis of motor and behavioural dynamics in 9-month-old preterm and term-born infants during changing emotional and interactive contexts

Computational analysis of infant movement has significant potential to reveal markers of developmental health. We report two studies employing dynamic analyses of motor kinematics and motor behaviours, which characterise movement at two levels, in 9-month-old infants. We investigate the effect of preterm birth (< 33 weeks of gestation) and the effect of changing emotional and social-interactive contexts in the still-face paradigm. First, multiscale permutation entropy was employed to analyse acceleration kinematic timeseries data collected from Inertial Measurement Unit (IMU) sensors on infants' torso, wrists, and ankles (N = 32: 10 term; 22 preterm). Second, Recurrence Quantification Analysis was used to characterise patterns of second-to-second behavioural changes, from observationally coded behavioural timeseries on infants' emotional self-regulation (N = 111: 61 term; 50 preterm). We found frequency-specific effects of context on permutation entropy. Relative to infants born at term (> 37 weeks of gestation), infants born preterm showed greater permutation entropy in their left ankle and torso movements, but not in right ankle or wrist movements. We did not find effects of preterm birth or emotional context on micro-level behavioural dynamics. Our methodology and findings inform future work using multiscale entropy to study infant development. Dynamic analysis of behaviour is a relatively young field, and applications to emotional self-regulation requires further methodological development.

Is it possible to monitor fetal movements with a wearable device? A review of novel technologies

Stillbirth is often preceded by reduced fetal movements and obstetric intervention is necessitated for stillbirth prevention. Yet, despite fetal movements being one of the few tangible ways a pregnant woman and the clinical team can assess the wellbeing of her baby, there are few validated, objective means for pregnant women to quantify the frequency and nature of an unborn baby's movements. Traditional methods of assessing fetal wellbeing such as cardiotocography and fetal movement charts have a lack of diagnostic accuracy, and often lead to false positive intervention. The need for fetal movement counting has led to the development of objective methods to attempt to quantify movements. Some are based on electrocardiography, others on the principles of accelerometery, phonography and optical fibre technology. This review paper not only explores these technologies and evaluates the state-of the-art fetal movement monitoring, but this review uniquely explains the engineering principles underpinning the various technologies, and explores the importance and practice of fetal movement monitoring. To this end, we conclude that there is still a need for the continued development of innovations which will enable a pregnant woman to carry out everyday activities, whilst confident in the knowledge that her unborn child's wellbeing is being accurately monitored, and that feedback from the monitoring device is readily accessible to her.

Association Between Television Viewing and Sensory Reactivity in Childhood: The Cross-Sectional InProS Study

BACKGROUND

Current evidence suggests a potential detrimental effect of increased television viewing on children's health, including sensory processing issues. Therefore, this study examined the association between television viewing time and atypical sensory reactivity (SR) in children aged from three to seven years.

METHODS

We evaluated data from the InProS cross-sectional study (n = 545). Daily television viewing was categorized into tertiles: ≤1.5, 1.5 to 2.5, and ≥2.5 hours. SR was evaluated using the Short Sensory Profile (SSP). Children with atypical SR were those with a global SSP score below 155, 30 for tactile sensitivity, 15 for taste/olfactory sensitivity, 13 for movement sensitivity, 27 for under-responsive/seeks sensation, 23 for auditory filtering, 26 for low energy/weak, and 19 for visual/auditory sensitivity. We used multiple Poisson regression models with robust variance to explore associations.

RESULTS

After adjusting for covariates, children who watched television 1.5 to 2.5 and ≥2.5 hours/day showed a higher prevalence of atypical global SR (prevalence ratio [PR]: 1.54; 95% confidence interval [CI]: 1.03 to 2.30; PR: 1.81; 95% CI: 1.19 to 2.76, respectively) and auditory filtering (PR: 1.50; 95% CI: 1.15 to 1.96; PR: 1.36; 95% CI: 1.01 to 1.83, respectively), compared with children who watched ≤1.5 hours/day. In addition, watching television ≥2.5 hours/day, compared with watching ≤1.5 hours/day, was associated with having atypical SR in movement sensitivity (PR: 1.73; 95% CI: 1.06 to 2.83), under-responsive/seeks sensation (PR: 1.31; 95% CI: 1.02 to1.69), and low energy/weak (PR: 2.02; 95% CI: 1.01 to 4.06).

CONCLUSIONS

The findings showed that television viewing ≥1.5 hours/day was associated with a higher prevalence of atypical SR in childhood. However, further longitudinal studies are required to confirm these results.

Early pain findings in infants with brachial plexus birth injury: Relationship with function and comorbidities, and cut-off point for fractures

BACKGROUND

Infants with birth brachial plexus injury (BPBI) may have various comorbidities such as fractures, torticollis, plagiocephaly, central nervous system disorders. In infants with BPBI, it is important to identify fractures, which are common among comorbidities, objectively assess pain, and investigate factors that may be associated with pain.

AIM

The aim of this study is to determine the pain level, comorbidities, and motor function in infants with BPBI and to examine the relationship between these parameters. The second aim is to determine the cut-off value of the pain score that may be a sign of fracture in patients with BPBI, in order to suspect and predict a fracture in the shoulder region and to request additional examinations.

SUBJECTS AND MEASUREMENTS

59 infants with BPBI aged 15-90 days were included in the study. Comorbidities, active joint movements, and total upper extremity function assessed with the Active Movement Scale and pain scores measured with the FLACC Pain Scale were retrospectively analyzed. In addition, pain, comorbidities and motor function were investigated according to types of Narakas, which indicates the degree of nerve injury.

RESULTS

Of the 59 participants, 18 (30.5 %) had at least one comorbidity and 12 (20.3 %) had fractures. The number of comorbidities (p = 0.41), the number of fractures (p = 0.84), and the level of pain (p = 0.71) did not differ by types of Narakas. There was a moderate negative correlation between pain level and upper extremity motor function in upper trunk injuries (p < 0.5, -0.67 < r < -0.46). There was a difference in pain level measured by palpation (p < 0.01) and passive joint movement (p < 0.01) in infants with and without comorbidities. To suspect a fracture in the shoulder region and to request further evaluation, the cut-off value of the Flacc pain level, which may predict a fracture, was 3.5 points for palpation and passive shoulder abduction and 4.5 points for passive external rotation.

CONCLUSION

This is the first study in the BPBI to measure pain in infants using a quantifiable and widely used assessment. Pain level was ranked from high to low as infants with fractures, infants with comorbidities other than fractures and infants without comorbidities. Increased pain adversely affects motor function and pain above the cut-off values is a predictor of fracture.

Effects of exercise training programs on motor skills of individuals with intellectual disabilities: a systematic review and meta-analysis

PURPOSE

Motor skills are involved in many physical activities and are prerequisites for the performance of sport skills. The purpose of this systematic review was to examine the effects of exercise training programs (ETP) on the motor skills of individuals with intellectual disabilities (IwID).

METHODS

Primary sources were obtained from four databases including PubMed, SCOPUS, CENTRAL, and Web of Science. The search period covered years from inception to October 26th, 2023. Inclusion criteria were as follows: Population: IwID; Intervention: ETP; Comparator: motor skills vs. nontraining control; Outcomes: motor skills outcomes. Standardized mean differences, weighted mean differences, and 95% confidence intervals (CI) were calculated using both random and fixed-effect models for outcomes.

RESULTS

A total of 14 studies involving 586 participants were included in the systematic review. The results of the present meta-analysis showed that ETP improved composite motor skills (1.28 95% CI: [0.86, 1.70], p = 0.001), gross motor skills (0.91, 95% CI: [0.62,1.19], p = 0.001), fine motor skills (0.74, 95% CI: [0.21,1.27], p = 0.01) and fine-gross motor skills (0.64, 95% CI: [0.29, 1.00], p = 0.001).

CONCLUSION

The results meta-analysis demonstrated that ETP improves the motor skills of IwID. Therefore, it is recommended to apply ETP to improve the motor skills of the IwID.

Quantifying spontaneous infant movements using state-space models

Over the first few months after birth, the typical emergence of spontaneous, fidgety general movements is associated with later developmental outcomes. In contrast, the absence of fidgety movements is a core feature of several neurodevelopmental and cognitive disorders. Currently, manual assessment of early infant movement patterns is time consuming and labour intensive, limiting its wider use. Recent advances in computer vision and deep learning have led to the emergence of pose estimation techniques, computational methods designed to locate and track body points from video without specialised equipment or markers, for movement tracking. In this study, we use automated markerless tracking of infant body parts to build statistical models of early movements. Using a dataset of infant movement videos (n = 486) from 330 infants we demonstrate that infant movement can be modelled as a sequence of eight motor states using autoregressive, state-space models. Each, motor state Is characterised by specific body part movements, the expression of which varies with age and differs in infants at high-risk of poor neurodevelopmental outcome.

Commercial infant products influence body position and muscle use

The musculoskeletal and motor development of infants is affected by their environment, which varies from being held, lying on a firm flat surface, to seated in various nursery products. Nursery products can alter the body position of infants, particularly the position of the head/neck and trunk, which may inhibit an infant's ability to breathe. With U.S. infants spending an increasing amount of time in seated products, the purpose of this study was to assess muscle activation and body position in four commercial infant products (carrier, bouncer, rocker, and swing) during supine and prone positioning, compared to a firm flat surface. Thirteen healthy infants (age: 4.2 ± 1.4 months; 7 M/6F) were enrolled in this IRB-approved in-vivo biomechanics study. Surface electromyography sensors recorded muscle activity of the erector spinae, cervical paraspinals, quadriceps, and abdominal muscles and retro-reflective markers tracked movements to determine head-neck, trunk, and torso-pelvis flexion/extension in the sagittal plane. While supine, infants exhibited increased head-neck and trunk flexion of up to 21° and 27° above the playmat, respectively, in all seated products. While prone, high abdominal muscle activation compared to the playmat indicates that infants will fatigue faster in seated products. Additionally, the lower muscle activation levels exhibited in younger infants (< 4 months) compared to older infants (≥ 4 months) indicates that younger infants rely on the product design to maintain body position. However, offering infants a variety of environments to move within is important to avoid motor delay, therefore future work should explore how long-term use may impact an infant's development.

I tap myself, and you tap me: bimanual predictive and reactive grip force control as a function of age

We investigated the effect of age on predictive and reactive grip force control. We compared the coupling between the grip and load force when participants tapped the object (i.e., self-TAP condition) held in their contralateral hand or when the experimenter tapped the object (i.e., external-TAP condition). Participants held the object either with their dominant or their non-dominant hands. Neurophysiological changes occur in the brain throughout childhood, so we hypothesized that these changes would make motor prediction less reliable in adolescents than adults. We compared adolescents' predictive and reactive grip force control (n = 19) to adults (n = 19). We quantified the coupling between grip and load forces using cross-correlation. The lags determined whether peak grip force occurred before (predictive control) or after (reactive control) peak load force. In the self-TAP condition, the change in grip force occurred significantly earlier in adults compared to adolescents by ~ 24 ms for the dominant and ~ 12 ms for the non-dominant hands. During the external-TAP condition, the peak grip force lagged the peak load force for both groups, but the lags were shorter for adolescents than adults for both hands. Smaller finger sizes with larger neural afferent density could enhance the cutaneous reflex responses caused by the sudden change in loading. For the self-TAP condition, results confirmed less efficient motor prediction in adolescents. Morphological and neurophysiological changes unfold in the developing brain during childhood; they can introduce variability into the neural circuits responsible for refining motor prediction.

Effects of 8 weeks of rhythmic physical activity on gross motor movements in 4-5-year-olds: A randomized controlled trial

Objective

Rhythmic physical activity holds promise for positively influencing the gross motor development of 4-5-year-old children, yet empirical research in this domain remains limited. This study aimed to investigate the effects of rhythmic physical activity on the gross motor development in children aged 4-5 years.

Methods

Fifty children aged 4-5 years were recruited and randomly assigned to either the intervention or control group. Both groups participated in a 10-week intervention program facilitated by a professional trainer, with support from numerous dedicated volunteers from reputable sports universities. This program comprised a one-week baseline assessment followed by 8 weeks of rhythmic physical activity training conducted three times per week. Gross motor performance was assessed using the PGMQ scale before and one week after the intervention.

Results

Following the 8-week intervention, the intervention group demonstrated significant enhancements in displacement ability, with notable improvements observed in. Specifically, the scores for running, sliding lateral transfer, leaping step, two-footed back-and-forth jump, and total displacement ability showed significant increases (P < 0.05). Moreover, the total scores for running, standing long jump, sliding lateral transfer, leaping step, two-footed back-and-forth jump, and displacement ability exhibited significant differences between the intervention and control groups (P < 0.05). Regarding manipulative ability, the intervention group showed significant increases in scores for over-the-shoulder throwing, two-handed catching, and kicking (P < 0.05). Moreover, there were significant differences between groups in the scores for two-handed catching and kicking (P < 0.05). Concerning balance ability, the intervention group exhibited significant improvements in scores for single-leg stand, double-leg stand, and total balance ability (P < 0.05). No significant differences were observed in any of the indices within the control group (P > 0.05). The two-way repeated measures ANOVA of intervention × time revealed significant differences in scores for running, sliding lateral movement, leaping step, jumping back and forth with both feet, leading ability, kicking, manipulation ability, single-leg stand, double-leg stand, balance ability, and gross motor scores (P < 0.05).

Conclusions

This study underscores the beneficial impact of engaging in eight weeks of rhythmic physical activity on the gross motor development of 4-5-year-olds. Furthermore, the improvements in gross motor development achieved through rhythmic physical activity may surpass those obtained through general physical activity.

Automatic gait evoking in healthy adults through Vojta's peripheric somatosensory stimulation: a double-blind randomized controlled trial

BACKGROUND

To study the effects of different interventions on automatic gait processing in contrast with voluntary gait processing in healthy subjects.

METHODS

A double-blind randomised controlled trial was designed (120 able-body persons between 18 and 65 years old entered and completed the study), with pre-intervention and post-intervention assessments using the 6-Minute Walk Test (6MWT). The participants were randomly distributed into four groups. Prior to intervention, all participants performed voluntary gait on the ground (VoG) in a calibrated circuit following the 6MWT. The presence of automatic gait (AG) was explored post-intervention without a voluntary demand in the same circuit following the 6MWT. Each group received a different intervention for 30 min: Vojta stimulation, MOTOMED® at no less than 60 revolutions/minute, treadmill walking at 3 km/h, and resting in a chair (control). The main assessment, conducted by a blinded rater, was the difference in distance covered (in meters) during the 6MWT between pre- and post-intervention. Surface electromyography (sEMG) average root mean square (RMS) signals in the right tibialis anterior, right soleus, right rectus femoris, and right biceps femoris were also considered outcome measures.

RESULTS

The Vojta group was the only one that initiated AG after the intervention (476.4 m ± 57.1 in VoG versus 9.0 m ± 8.9 in AG, p < 0.001) with comparable kinematics and EMG parameters during voluntary gait, except for ankle dorsal flexion. Within the Vojta group, high variability in kinematics, sEMG activity, and distance covered was observed.

CONCLUSIONS

AG isolation is approachable through Vojta at only one session measurable with the 6MWT without any voluntary gait demand. No automatic gait effects were observed post-intervention in the other groups.

TRIAL REGISTRATION

NCT04689841 (ClinicalTrials.gov).

Cognitive and motor improvement by tummy time practice in preemies from low-income settings: a randomized clinical trial

Introduction

Early intervention and parental education for preemies are limited in some low-income countries. Thus, this study aimed to assess whether daily tummy time (TT) associated with usual care (UC) enhances motor and cognitive development in preemies from low-income countries. The main and secondary aim was to assess prone head elevation (PHE) and motor and cognitive functions, respectively.

Methods

Thirty-one preemies with a mean gestational age at birth of 33.3 ± 1.6 weeks and weighing <2,500 g were included and 18 completed all assessments. Parents from the TT group were asked to perform TT with their preemies for at least 20 min during daily activities and playtime. Motor and cognitive functions were assessed by a blinded examiner using the motor and cognitive composite scores of Bayley-III after two and four months of corrected age. PHE was given by the angle from the tragus of the ear to the supporting surface of the infant; measurements were obtained using the Kinovea® software at baseline, after two, three, and four months of corrected age.

Results

The Bayley-III motor composite score of the TT group was higher than the UC group after two and four months of corrected age. The PHE angle increased over time but did not differ between groups.

Discussion

Nevertheless, TT expanded the perspective of preemies to explore their bodies and environment, favoring the stimuli for motor and cognitive patterns. The loss of participants (31%) was one of the limitations of the study, illustrating the challenge of providing continued early interventions to preemies from low-income countries. In this sense, TT practice is a home intervention that may improve motor and cognitive function of preemies immediately after hospital discharge.

Effect of swimming initiation period and continuation frequency on motor competence development in children aged up to 3 years: the Japan environment and children's study

BACKGROUND

Although involvement of toddlers in swimming activities has increased recently, information regarding the impact of swimming during toddlerhood on subsequent child motor competence development is scarce. This study aimed to determine how swimming experience, particularly the timing of initiation and the continuity of swimming activities up to the age of 3 years, affects motor competence development.

METHODS

This prospective cohort study included data on children aged 1.5 and 3 years (100,286 mother-child pairs) from the Japan Environment and Children's Study. The outcomes measured were gross and fine motor function, using the Japanese version of the Ages and Stages Questionnaire (Third edition). We assessed how these functions correlated with the continuous pattern of swimming pool use frequency from age 1 up to 3 years.

RESULTS

The group that used a swimming pool once a month or more from age 1-1.5 years but stopped from age 2-3 years showed consistently significant negative associations with gross motor development delay (minimum adjusted odds ratio [aOR]: 0.66, 95% confidence interval [CI]: 0.60-0.73) and fine motor development delay (minimum aOR: 0.66, 95% CI: 0.58-0.76). The group that continued swimming once a month or more from age 1-3 years showed consistently significant negative associations with gross motor development delay (minimum aOR: 0.64, 95% CI: 0.54-0.75) and fine motor development delay (minimum aOR: 0.42, 95% CI: 0.31-0.55).

CONCLUSIONS

These results suggest that swimming experience starting around age 1 year is positively associated with gross and fine motor function development. The beneficial impact on gross motor function persisted from age 1-3 years. In contrast, the effects on fine motor function were not evident until age ≥ 2.5 years after starting swimming at approximately age 1 year. These findings underscore the potential benefits of early swimming experiences in enhancing overall motor skills development during early childhood.

Relationship between sensory processing skills and motor skills in 12-month-old infants

INTRODUCTION

Identifying sensory processing problems of 12-month-old preterm and term children and defining their relationship with motor skills are essential for appropriate interventions and optimal sensory-motor development. This study aimed to determine sensory processing difficulties in 12-month-old babies and examine their relationship with motor skills.

METHODS

This cross-sectional study included 61 infants (28 preterm and 33 full-term, ages 12 months). The infants' sensory processing skills were evaluated using the Test of Sensory Functions in Infants (TSFI), and their gross and fine motor skills were assessed with the Peabody Developmental Motor Scales-2 (PDMS-2).

RESULTS

Sensory processing difficulties were more common in preterm babies. Multiple linear regression models indicated a significant positive association between PDMS-2 gross/fine motor scores and TFSI total scores, reactivity to tactile deep pressure, and ocular-motor control in the total sample. Furthermore, there was a relationship between gross motor and adaptive motor function, and fine motor scores were found to be associated with visual-tactile integration sensory scores.

CONCLUSIONS

Preterm babies are more likely than their full-term peers to have sensory processing problems around the age of one, which can affect their motor skills. The results support the relationship between children's sensory and motor processing skills. Practitioners such as occupational and physical therapists should be alert to this relationship in infants with sensory processing and motor problems. Taking this relationship into consideration when planning intervention programs can be a guide for an effective intervention.

The Importance of Follow-Up Visits for Children at Risk of Developmental Delay-A Review

Structured follow-up visits should be accessible for children at risk for developmental delay. Follow-up visits should include a serial neuromotor assessment in the first two years of life (e.g., 3-6, 12, 24 months corrected age), which are repeated during the transition to school. The diagnosis of neuromotor development may be prognostic for important skills later in life. The early diagnosis of a child's general movements can be helpful in planning appropriately for proper treatment and intervention. These diagnostic assessments should be conducted by qualified healthcare professionals. The evaluation of neuromotor developmental health is specified in the national guidelines and funded by either a national government or public or private healthcare insurance and based on standardized assessment scales. The aim of this study is to show what elements of follow-up visits are recommended.

OBJECTIVES

The group of patients for whom the structured follow-up systems are intended were children born very preterm (<32 weeks gestation) or full-term born children with severe neonatal complications.

MATERIAL AND METHODS

The methods for monitoring neurodevelopment include the following: The General Movements Assessment (GMA), the Ages and Stages Questionnaire (ASQ-3), the Bayley Scales of Infant and Toddler Development (BSID-4), and the Parent Report of Children's Abilities-Revised (PARCA-R).

RESULTS

The results of follow-up visits should be registered.

CONCLUSIONS

The benefits of follow-up neuromotor development assessments can be observed at school age and even in adulthood.

Prenatal and Early Life Exposure to Ambient Air Pollutants Is Associated with the Fecal Metabolome in the First Two Years of Life

Prenatal and early life air pollution exposure has been linked with several adverse health outcomes. However, the mechanisms underlying these relationships are not yet fully understood. Therefore, this study utilizes fecal metabolomics to determine if pre- and postnatal exposure to ambient air pollutants (i.e., PM10, PM2.5, and NO2) is associated with the fecal metabolome in the first 2 years of life in a Latino cohort from Southern California. The aims of this analysis were to estimate associations between (1) prenatal air pollution exposure with fecal metabolic features at 1-month of age, (2) prior month postnatal air pollution exposure with fecal metabolites from 1-month to 2 years of age, and (3) how postnatal air pollution exposure impacts the change over time of fecal metabolites in the first 2 years of life. Prenatal exposure to air pollutants was associated with several Level-1 metabolites, including those involved in vitamin B6 and tyrosine metabolism. Prior month air pollution exposure in the postnatal period was associated with Level-1 metabolites involved in histidine metabolism. Lastly, we found that pre- and postnatal ambient air pollution exposure was associated with changes in metabolic features involved in metabolic pathways including amino acid metabolism, histidine metabolism, and fatty acid metabolism.

Motor performance of Indian preterm infants as compared to the US population on the Test of Infant Motor Performance (TIMP)

PURPOSE

The study aimed at scoring Indian preterm infants at three months corrected age on the TIMP and then comparing the scores to the United States age-based population scores.

METHODS

After obtaining Ethical clearance, participants meeting the inclusion criteria of 53 infants whose parents consented were screened and recruited (N = 47) at a tertiary care hospital. The TIMP was then administered at three months of corrected age.

RESULTS

Data obtained from 47 infants born preterm (Male = 33, Female = 14) at three months corrected age with mean gestational age (34.4 ± 2.36 weeks) and mean birth weight (1.93 ± 0.55 kgs) was analyzed. Indian infants born preterm scored a mean of (98.17 ± 20.90) compared to the US mean of (108 ± 19), suggesting an under-performance. The average scores were lower when comparing the mean of the study group with the US-based age-matched population.

CONCLUSION

Motor performance scores of Indian preterm infants were low when compared to their US counterparts. Since there exists a difference in the raw score obtained by Indian Preterm infants compared to the US-based population, it may not be appropriate to categorize the motor development of Indian infants based on the US population scores.

Prevalence and socio-economic determinants of growth and developmental delays among Iranian children aged under five years: A cross sectional study

BACKGROUND

The main cause of growth and development delays remains unknown, but it can occur as an interaction between genetic, environmental, and socio-economic factors.

OBJECTIVE

The aim of the study was to investigate the prevalence and social determinants of growth and developmental delays among children aged under five years in Qazvin, Iran.

METHODS

A cross-sectional study was conducted between January 2019 to December 2020 with participation of 1800 mothers with children aged 4-60 months who were referred to comprehensive health centers in Qazvin city, Iran. Structural and intermediate social determinants of health were assessed including: parents and children socio-demographic characteristics, families' living and economic status, parents' behavioral factors, household food security, mother's general health, and perceived social support. Children's growth was assessed based on their anthropometric assessment and their development was assessed using their age-specific Ages and Stages Questionnaire. Data were analyzed using univariable and multivariable logistic regression models using SPSS software version 24 and Stata version 14.

RESULTS

The prevalence of developmental problems in each domain were 4.28% for personal and social delay, 5.72% for gross motor delay, 6.5% for communication delay, 6.72% for fine motor delay, and 8% for problem-solving delay. The prevalence of weight growth delays was 13.56% and height growth delays was 4.66%. Communication, gross motor, and problem-solving delays were higher among children whose fathers' smoked cigarettes. Fine motor delays were lower among mothers with education status of high school diploma and university degree vs. the under diploma group. Personal and social delay was significantly higher among families with fair economic status and lower among children when their fathers were employed (vs. unemployed). Weight and height growth delays were higher among mothers who had experienced pregnancy complications and household food insecure families, respectively.

CONCLUSION

There are different predictors of growth and developmental delay problems among Iranian children aged under five years including fathers' smoking, families' economic status, and household food insecurity as well as history of mothers' pregnancy complications. The present study's findings can be used to screen for at-risk of growth and developmental delays among children and could help in designing and implementation of timely interventions.

Development of eating skills in infants and toddlers from a neuropediatric perspective

Early infant feeding and swallowing are complex motor processes involving numerous muscles in coordination, e.g. the orofacial muscles as well as the muscles of the pharynx, larynx and esophagus. The newborn's reflexive drinking develops into the ability to ingest pureed complementary food as infancy progresses. Finally, in the last part of the first year of life, a differentiated eating, chewing and swallowing process develops allowing the voluntary intake of different foods of the family diet. The dietary schedule for the first year of life, which describes the recommended nutrition of infants in Germany, corresponds to these milestones in eating development. Disturbances in gross motor development, sensory processing issues, and organic and behavioral problems are known to interfere with the development of eating skills. Swallowing disorders (dysphagia) in children can have a detrimental effect on food intake and pose a serious risk to growth and development. Their prevention treatment requires a multidisciplinary approach with the aim of enabling the child to eat independently in the long term.

Motor and cognitive response to intensive multidisciplinary therapy: the first reported case of congenital Zika virus syndrome

PURPOSE

To provide a detailed description of the development of the first case of congenital Zika syndrome (CZS) to be reported in the literature worldwide.

CASE DESCRIPTION

This report describes the case of a child with CZS monitored from pregnancy until four years of age, with periodic evaluations of head circumference, weight, height, motor function according to the Gross Motor Function Measure (GMFM-88), and the occurrence of comorbidities.

OUTCOMES

The child's birth weight and length were normal (z-score = 1.1 and -1.95, respectively), while head circumference was below the expected value (z-score = -3.15). At 48 months, head circumference reached 43 cm (z-score = -4.48). During daily home physiotherapy sessions, the child achieved developmental milestones, standing unsupported at 17 months, with a GMFM-88x score of 137. With specialist therapy, the child walked independently at 36 months and a total GMFM-66 score of 214 was achieved by 42 months. In the four years of follow-up, the child was hospitalized four times for different reasons. No convulsive seizures occurred.

CONCLUSIONS

Despite severe neurological impairment, the child's weight and height are adequate for age, with motor and cognitive function improving over the first four years of life.

Objective measurement of movement variability using wearable sensors predicts ASD outcomes in infants at high likelihood for ASD and ADHD

Early motor delays and differences are common among children with autism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder (ADHD). Yet, little work has shown whether there are early atypical motor signs that differentiate these groups. Quantitative measures of movement variability hold promise for improving the identification of subtle and specific differences in motor function among infants and toddlers at high likelihood for ASD and ADHD. To this end, we created a novel quantitative measure of movement variability (movement curvature) and conducted a preliminary investigation as to whether this measure improves outcome predictions. We used a wearable triaxial accelerometer to evaluate continuous motion-based activity in infants at high and low likelihood for ASD and ADHD at 12, 18, 24, and 36 months of age. At 36 months, participants were categorized into three outcome groups: ASD (n = 19), ADHD concerns (n = 17), and a comparison group (n = 82). We examined group differences in movement curvature and whether movement curvature is predictive of a later ASD or ADHD concerns classification. We found that movement curvature was significantly lower in infants with later ASD diagnosis at 18, 24, and 36 months of age compared to infants with either ADHD concerns or those in the comparison group. Movement curvature was also a significant predictor of ASD at 18, 24, and 36 months (AUC 0.66-0.71; p = 0.005-0.039) and when adjusting for high ASD likelihood at 18 and 24 months (AUC 0.90, p = 0.05-0.019). These results indicate that lower movement curvature may be a feature of early motor differences in infants with later ASD diagnosis as early as 18 months of age.

Mechanical environment influences muscle activity during infant rolling

An infant's musculoskeletal and motor development is largely affected by their environment. Understanding how different mechanical environments affect an infant's movements and muscle use is necessary to inform the juvenile products industry and reduce incidents involving inclined nursery products each year. The purpose of this study was to determine how the coordinated movements and corresponding muscle activation patterns are affected by different mechanical environments, specifically the back incline angle. Thirty-eight healthy infants (age: 6.5 ± 0.7 months; 23 M/15 F) were enrolled in this IRB-approved in-vivo biomechanics study. Surface electromyography sensors recorded muscle activity of the erector spinae, abdominal muscles, quadriceps, and hamstrings while infants rolled in five different mechanical environments: a flat surface and four device configurations representing a range of inclines infants are commonly exposed to. Coordinated movements were determined using video. In all configurations featuring an inclined seatback angle, infants experienced significantly higher erector spinae muscle activation and significantly lower abdominal muscle activation compared to the flat surface. Infants also exhibited a different coordinated movement featuring spinal extension and a pelvic thrust in the inclined device configurations that was not previously observed on the flat surface alone. Understanding how infants coordinate their movements and use their muscles during rolling in different inclined environments provides more insight into motor development and may inform the juvenile products industry. Many factors impact an infant's movements, therefore future work should explore how other environmental interactions influence an infant's movements and muscle activation, particularly for rolling.

Statistical shape analysis of the lentiform nucleus of children of different age groups: a retrospective study

The basal nuclei are important during infancy because of the significant development of motor skills. The main aim of this study was to evaluate the shape differences of the lentiform nucleus between different age and gender groups. A total of 126 children's axial magnetic resonance image series were included in the presented study. These images were grouped between 1 and 5 yr old. Right and left lentiform nuclei are marked with selected landmarks using TPSDIG v2.04. Statistical shape analyses were examined by a Generalized Procrustes Analysis. Our results showed that there was no statistically significant difference in lentiform nucleus shape between genders. However, there was a difference between the shapes of the right and left lentiform nuclei between the 1-yr and 5-yr age groups. These results demonstrated the shape changes in the lentiform nucleus during the first 5 yr of life. Further clinical studies based on our results may be used to gather more detailed information about movement disorders and neuronal development.

Kids+ Parent Infant Program (PIP): a community model for supporting partnerships in early developmental follow-up and support

High-risk infants are discharged home from hospital with increased care needs and the potential for the emergence of developmental disabilities, contributing to high levels of parental stress and anxiety. To enable optimal outcomes for high-risk infants and their families, developmental follow-up programs need to continue following hospital discharge. However, current follow-up care for high-risk infants is variable in terms of type, access and equity, and there seems to be a gap in existing services such as supporting the transition home, parental support, and inclusion of all at-risk infants regardless of causality. Routine follow-up that identifies developmental delays or neuromotor concerns can facilitate timely referral and access to targeted intervention during critical periods of development. The Kids+ Parent Infant Program (PIP) is a unique model of developmental follow-up that shares some characteristics with established programs, but also includes additional key elements for a seamless, wrap-around service for all high-risk infants and their families living in a regional area of Australia. This community-based program provides integrated assessment and intervention of infants, alongside parent support and education, embracing a holistic model that accounts for the complexity and interrelatedness of infant, parent, medical and developmental factors. By prioritising the well-being of high-risk infants and their families, the Kids+ PIP paves the way for improved developmental outcomes and provides an innovative model for developmental follow-up, with the potential for reproduction in other healthcare settings.

Sensorimotor Oscillations in Human Infants during an Innate Rhythmic Movement

The relationship between cerebral rhythms and early sensorimotor development is not clear. In recent decades, evidence revealed a rhythmic modulation involving sensorimotor processing. A widely corroborated functional role of oscillatory activity is to coordinate the information flow across sensorimotor networks. Their activity is coordinated by event-related synchronisation and desynchronisation in different sensorimotor rhythms, which indicate parallel processes may be occurring in the neuronal network during movement. To date, the dynamics of these brain oscillations and early sensorimotor development are unexplored. Our study investigates the relationship between the cerebral rhythms using EEG and a typical rhythmic movement of infants, the non-nutritive sucking (NNS) behaviour. NNS is an endogenous behaviour that originates from the suck central pattern generator in the brainstem. We find, in 17 infants, that sucking frequency correlates with beta synchronisation within the sensorimotor area in two phases: one strongly anticipating (~3 s) and the other encompassing the start of the motion. These findings suggest that a beta synchronisation of the sensorimotor cortex may influence the sensorimotor dynamics of NNS activity. Our results reveal the importance of rapid brain oscillations in infants and the role of beta synchronisation and their possible role in the communication between cortical and deep generators.

Early movement restriction affects the acquisition of neurodevelopmental reflexes in rat pups

Childhood is a period of construction of the organism, during which interactions with the environment and regular physical activity are necessary for the maturation of the neuronal networks. An atypical sensorimotor activity during childhood (due to bed-rest or neurodevelopmental disorders) impacts the development of the neuromuscular system. A model of sensorimotor restriction (SMR) developed in rats has shown that casting pups' hind limbs from postnatal day 1 (P1) to P28 induced a severe perturbation of motor behavior, due to muscle weakness as well as disturbances within the central nervous system. In the present study, our objective was to determine whether SMR affects the early postnatal ontogenesis. We explored the neuromuscular development through the determination of the age for achievement of the main neurodevelopmental reflexes, which represent reliable indicators of neurological and behavioral development. We also evaluated the maturation of postural control. Our results demonstrate that SMR induces a delay in the motor development, illustrated by a several days delay in the acquisition of a mature posture and in the acquisition reflexes: hind limb grasping, righting, hind limb placing, cliff avoidance, negative geotaxis. In conclusion, impaired physical activity and low interactions with environment during early development result in altered maturation of the nervous system.

Association of Breastfeeding and Neonatal Jaundice With Infant Neurodevelopment

INTRODUCTION

Exclusive breastfeeding is advantageous for infant neurodevelopment. Nevertheless, insufficient human milk supply in exclusively breastfed infants may elevate the risk of neonatal jaundice, which can potentially result in neurological harm. Whether mothers should adhere to exclusive breastfeeding in infants with neonatal jaundice remains unclear.

METHODS

Data comes from the Jiangsu Birth Cohort (JBC), a prospective and longitudinal birth cohort study in China. A total of 2,577 infants born from November 2017 to March 2021 were included in the analysis. Multivariate linear regression models were used to analyze the associations between breastfeeding status, neonatal jaundice, and their interaction with infant neurodevelopment. Analysis was performed in 2022.

RESULTS

Compared with "exclusive breastfeeding," fine motor scores of infants were lower for "mixed feeding" (βadj, -0.16; 95% CI, -0.29 to -0.03; p=0.016) and "no breastfeeding" (βadj, -0.41; 95% CI, -0.79 to -0.03; p=0.034). Compared with "no neonatal jaundice," infants with "severe neonatal jaundice" had lower scores for cognition (βadj, -0.44; 95% CI, -0.66 to -0.23; p<0.001) and fine motor (βadj, -0.19; 95% CI, -0.35 to -0.03; p=0.024). In infants with severe neonatal jaundice, the termination of exclusive breastfeeding before 6 months was associated with worse cognition (βadj, -0.28; 95% CI, -0.57 to 0.01), while this association was not observed in those without neonatal jaundice (βadj, 0.09; 95% CI, -0.26 to 0.43).

CONCLUSIONS

Exclusive breastfeeding for the first 6 months is beneficial to the neurodevelopment of infants, especially in those with severe neonatal jaundice.

Is it possible to identify physical-motor profiles of preschool children on their association with selected biosocial factors?

Biosocial factors play a crucial role in the physical-motor development (PMD) of children during the preschool age. The present study aims to identify physical-motor profiles throughout preschool age (3-6 years) and explore associations between profiles and selected biosocial factors such as age, sex, prematurity, weight, height, BMI, and participation in extracurricular physical activities. Data from 412 typically developing children (46.6% girls and 53.4% boys), aged 35-71 months (M = 51.21, SD = 10.47) was collected using the Psychomotor Activities Checklist and specifically the scale of Psycho-Motor Aspects. Cluster analysis made it possible to define four different childhood PMD profiles. High PMD; High PMD except left laterality; medium-low PMD; and low PMD. High PMD profile includes older children, with anthropometric measurements closer to the WHO recommendations, fewer preterm children, and greater participation in extracurricular physical activities. Low PMD profile includes younger children, with weight slightly above and height slightly below the WHO recommendations and low participation in extracurricular physical activities. This study allows us to identify specific trends that may be decisive for the motor development of children throughout preschool age, highlighting selected biological variables and participation in extracurricular physical activities.

[Quality of anthropometric data of children under 5 years in the Brazilian National Food and Nutrition Surveillance System, 2008-2020]

The planning, monitoring, and evaluation of food and nutrition actions depend on reliable estimates based on adequate anthropometric data. The study aimed to analyze the quality of anthropometric data of children aged under 5 years in the Brazilian National Food and Nutrition Surveillance System (SISVAN) from 2008 to 2020. The sample comprised 23,453,620 children aged under 5 years. Initially, we evaluated the distribution of missing values and values outside the spectrum of the instrument, and calculated the digit preference index for weight and height. The nutritional indexes height for age (HAZ), weight for age (WAZ), and body mass index for age (BAZ) were calculated according to the World Health Organization 2006 child growth standards. Then, we identified the biologically implausible values (BIV) and calculated the standard deviation (SD) of the nutritional indexes. For each municipality, we calculated the mean and SD of HAZ and WAZ; and plotted the SD values as a function of the mean. In all Federative Units, the digit preference index reached a minimum value of 80 for height and 20 for weight. For the three nutritional indexes, there was a reduction in the frequency of BIV in the 2008-2020 period. Even after the exclusion of BIV, we identified high variability for the three nutritional indexes. The indicators evaluated showed low quality of measurement, especially in the North and Northeast regions. Our results indicate insufficient quality of anthropometric data in children aged under 5 years, and reinforce the need to invest in actions to improve the collection and recording of anthropometric information.

Motor patterns of patients with spinal muscular atrophy suggestive of sensory and corticospinal contributions to the development of locomotor muscle synergies

Complex locomotor patterns are generated by combination of muscle synergies. How genetic processes, early sensorimotor experiences, and the developmental dynamics of neuronal circuits contribute to the expression of muscle synergies remains elusive. We shed light on the factors that influence development of muscle synergies by studying subjects with spinal muscular atrophy (SMA, types II/IIIa), a disorder associated with degeneration and deafferentation of motoneurons and possibly motor cortical and cerebellar abnormalities, from which the afflicted would have atypical sensorimotor histories around typical walking onset. Muscle synergies of children with SMA were identified from electromyographic signals recorded during active-assisted leg motions or walking, and compared with those of age-matched controls. We found that the earlier the SMA onset age, the more different the SMA synergies were from the normative. These alterations could not just be explained by the different degrees of uneven motoneuronal losses across muscles. The SMA-specific synergies had activations in muscles from multiple limb compartments, a finding reminiscent of the neonatal synergies of typically developing infants. Overall, while the synergies shared between SMA and control subjects may reflect components of a core modular infrastructure determined early in life, the SMA-specific synergies may be developmentally immature synergies that arise from inadequate activity-dependent interneuronal sculpting due to abnormal sensorimotor experience and other factors. Other mechanisms including SMA-induced intraspinal changes and altered cortical-spinal interactions may also contribute to synergy changes. Our interpretation highlights the roles of the sensory and descending systems to the typical and abnormal development of locomotor modules.NEW & NOTEWORTHY This is likely the first report of locomotor muscle synergies of children with spinal muscular atrophy (SMA), a subject group with atypical developmental sensorimotor experience. We found that the earlier the SMA onset age, the more the subjects' synergies deviated from those of age-matched controls. This result suggests contributions of the sensory/corticospinal activities to the typical expression of locomotor modules, and how their disruptions during a critical period of development may lead to abnormal motor modules.

Visuomotor tracking strategies in children: associations with neurodevelopmental symptoms

Children with neurodevelopmental disorders (NDDs) often display motor problems that may impact their daily lives. Studying specific motor characteristics related to spatiotemporal control may inform us about the mechanisms underlying their challenges. Fifty-eight children with varying neurodevelopmental symptoms load (median age: 5.6 years, range: 2.7-12.5 years) performed an interactive tablet-based tracking task. By investigating digit touch errors relative to the target's movement direction, we found that a load of neurodevelopmental symptoms was associated with reduced performance in the tracking of abrupt alternating directions (zigzag) and overshooting the target. In contrast, reduced performance in children without neurodevelopmental symptoms was associated with lagging behind the target. Neurodevelopmental symptom load was also associated with reduced flexibility in correcting for lateral deviations in smooth tracking (spiral). Our findings suggest that neurodevelopmental symptoms are associated with difficulties in motor regulation related to inhibitory control and reduced flexibility, impacting motor control in NDDs.

Qualitative age-related changes in fine motor skill performance among 3- to 6-year-old typically developing children

This study described intra-task fine motor skill components of the Manual Dexterity tasks (Posting Coins; PC, Threading Beads; TB, Drawing Trail; DT) of the Movement Assessment Battery for Children-2 Test for typically developing children and investigated age- and sex-related differences. Three- to six-year-old Dutch children (n = 182, Mage 4.5 ± 1.1 years, 51.1% boys) were observed with regard to intra-task fine motor skill components, and changes in intra-task components of the Manual Dexterity tasks were analyzed across age using of the Kruskal-Wallis test with post-hoc Mann-Whitney U tests, and differences between sexes using the Mann-Whitney U test. The following intra-task components were observed: grip type, manipulation, non-dominant or non-writing hand, grip position, posture, head, coin placement, placement of the bead on the lace tip and joint movement. Results showed that the younger children (3-year-olds) more frequently used a grasp with the full hand (PC, TB), more often put the coin on the container and sliding it in (PC), more often supported the side or top of the container (PC), used more bi-manual manipulation (transferring from hand-to-hand or hand, body or surface assist) (TB, DT), more frequently used primitive, too high grips, predominantly used their proximal joints, and did not support the paper (DT). This in comparison with more frequent use of three-point pinch, direct coin placement, grabbing the front or back of the container, in-hand-manipulation, mature grips and correct height, distal joint use and supporting the paper from the side or below by most 5- and 6-year-olds. Furthermore, most sex-related differences were found in the younger age-groups (3- and 4-year-olds) in the DT tasks with girls outperforming boys. Results from this study add to the knowledge on qualitative fine motor skill performance in a convenience sample of 3- to 6-year-old typically developing children. A limitation of the current study was the relatively small sample size of 6-year-old children. The strength of the current study is its novelty in providing qualitative descriptions of intra-task fine motor skill components in typically developing 3- to 6-year-old children.

Predicting Age of Independent Walking in Preterm Infants: A Longitudinal Study Using Neonatal Characteristics and Motor Development Variables

OBJECTIVE

To formulate an equation estimating months to independent walking in moderate to late preterm infants based on neonatal characteristics and gross motor development from 7 months to independent walking.

METHODS

Sixty infants born between 32 to 36 weeks were assessed using Alberta Infant Motor Scale (AIMS) for gross motor development. Neonatal characteristics were recorded at 7 months, and caregiver-reported independent walking onset. Pearson correlation analyzed age, AIMS scores, and neonatal factors. Multiple regression developed the prediction equation.

RESULTS

The equation for independent walking onset, which included gestational age (GA) at birth, total AIMS score at 10 months of age (10th AIMS), and birth head circumference (BHC), exhibited a strong correlation (r=0.707) and had a predictive power of 50.0%. The equation is as follows: age onset of independent walking (months)=33.157, -0.296 (GA), -0.132 (10th AIMS), -0.196 (BHC), with an estimation error of 0.631 months.

CONCLUSION

Neonatal characteristics, such as GA, 10th AIMS, and BHC, are key determinants in estimating the onset of independent walking in moderate to late preterm infants.

Optimization of modularity during development to simplify walking control across multiple steps

Introduction

Walking in adults relies on a small number of modules, reducing the number of degrees of freedom that needs to be regulated by the central nervous system (CNS). While walking in toddlers seems to also involve a small number of modules when considering averaged or single-step data, toddlers produce a high amount of variability across strides, and the extent to which this variability interacts with modularity remains unclear.

Methods

Electromyographic activity from 10 bilateral lower limb muscles was recorded in both adults (n = 12) and toddlers (n = 12) over 8 gait cycles. Toddlers were recorded while walking independently and while being supported by an adult. This condition was implemented to assess if motor variability persisted with reduced balance constraints, suggesting a potential central origin rather than reliance on peripheral regulations. We used non-negative matrix factorization to model the underlying modular command with the Space-by-Time Decomposition method, with or without averaging data, and compared the modular organization of toddlers and adults during multiple walking strides.

Results

Toddlers were more variable in both conditions (i.e. independent walking and supported by an adult) and required significantly more modules to account for their greater stride-by-stride variability. Activations of these modules varied more across strides and were less parsimonious compared to adults, even with diminished balance constraints.

Discussion

The findings suggest that modular control of locomotion evolves between toddlerhood and adulthood as the organism develops and practices. Adults seem to be able to generate several strides of walking with less modules than toddlers. The persistence of variability in toddlers when balance constraints were lowered suggests a link with the ability to explore rather than with corrective mechanisms. In conclusion, the capacity of new walkers to flexibly activate their motor command suggests a broader range of possible actions, though distinguishing between modular and non-modular inputs remains challenging.

Associations between Gross and Fine Motor Skills, Physical Activity, Executive Function, and Academic Achievement: Longitudinal Findings from the UK Millennium Cohort Study

Accumulating evidence from behavioral studies and neuroscience suggests that motor and cognitive development are intrinsically intertwined. To explore the underlying mechanisms of this motor-cognition link, our study examined the longitudinal relationship of early motor skills and physical activity with later cognitive skills. The sample was 3188 children from the United Kingdom Millennium Cohort Study, followed at 9 months and 5, 7, and 11 years. Early motor skills were examined at 9 months. Children's daily physical activity level was measured using accelerometers at 7 years and a questionnaire was conducted at 11 years. Cognitive skills, including executive function and academic achievement, were measured at age 11. The results suggest that gross motor skills were positively associated with spatial working memory, whereas fine motor skills were predictive of good English and science outcomes. Moderate-to-vigorous activity was found to be negatively associated with English performance, although self-reported activity frequency was positively linked to math. Our results highlight the significant role of both gross and fine motor skills in cognitive development. This study also elucidates the limitations of using activity intensity to assess the impact of motor activity on children's cognitive development, suggesting that attention to the effects of specific types of physical activity would better elucidate the motor/cognition link.

Physiotherapy Intervention on Premature Infants-A Pilot Study

Background and Objectives: Considering the fact that prematurity echoes in terms of motor development even up to the age of adolescence, through the presence of deficiencies, the importance of starting kinetotherapeutic treatment as soon as possible is highlighted, even in the absence of brain damage or obvious motor delays. Therefore, the objectives of this study are to analyze the factors that influence the level of motor development of premature babies up to 9 months and identify the motor development curve of premature babies according to the three stages of motor development: the position of symmetrical support on the elbows at 3 months, sitting with support at 6 months, and verticalization at 9 months. Materials and Methods: This prospective pilot study was conducted within a rehabilitation facility located in Targu Mureș, Romania, spanning a duration of 2 years from June 2021 to 2023. Results: The study involved a population of 78 children, all premature infants, selected from the patient pool of the rehabilitation facility, specifically chosen based on adherence to the predetermined inclusion and exclusion criteria outlined in the study protocol. Two physiotherapists specialized in child recovery were involved in the study, and one performed the assessments and the other applied the Bobath therapy. Conclusions: Early physiotherapy interventions can have a positive influence in terms of reducing differences in motor development between preterm and full-term infants. This study identified several factors that influence the motor development of premature infants. Among these, the most prominent biological factors were gestational age and birth weight.

Usability of the dynamic scaffolding system: an adaptive mobility device in children with special needs

PURPOSE

Maintaining vertical position and moving are essential to healthy development. Children with motor difficulties may need assistive devices to stand upright or move. The Dynamic Scaffolding System (DSS) device was developed to support these skills. This study aims to explain the DSS's developmental stages, compare the device's usage times based on diagnoses and motor impairment, and investigate the degree of satisfaction among parents of children using the device.

MATERIALS AND METHODS

The study included children with difficulty standing or stepping and their parents. We compared usage times of DSS depending on diagnosis (cerebral palsy (CP) or other diagnoses) and motor impairment levels. We assessed parental satisfaction by using the Quebec User Evaluation of Satisfaction with Assistive Technology (QUEST 2.0) and recorded adverse events.

RESULTS

The ages of the participants (n:100) were between 9 and 108 months (44.94 ± 17.59), and 60% of the children had CP, and 40% had other diagnoses (genetic, metabolic, neuromuscular diseases). The duration of daily use of DSS ranged from 44.17 (±26.16) to 110 (±97.98) minutes, and the duration was similar among children at different levels of motor impairment (p = 0.262). The parents were most satisfied with the size, simplicity of use, and effectiveness, and they were least satisfied with the ease of adjustment, safety, and durability. They did not report any adverse events during the study.

CONCLUSIONS

DSS can be considered a useable assistive device option for children with CP and other diagnoses with difficulty standing or stepping and a satisfactory device for parents of such children.

General movements assessment: A bibliometric analysis

This bibliometric analysis provides an in-depth exploration of the scholarly landscape in the field of Prechtl General Movement Assessment (GMA) research, spanning the period from 1961 to 2023. It offers valuable insights into the evolutionary trajectory and global impact of GMA. The study employs a longitudinal approach, meticulously tracking trends in scholarly output, international collaborations, and authorship patterns. Notably, our findings reveal a significant increase in GMA-related publications, highlighting the growing prominence of this field. The dominance of Australia and Austria in scholarly contributions underscores their pivotal roles. International collaborations are prominent, with active participation from European nations and the Americas. However, it is essential to acknowledge certain limitations, including potential data source biases and a reliance on English-language publications. This analysis serves as a valuable resource for stakeholders in the field, emphasizing the need for ongoing evaluation and collaborative efforts to enhance GMA applications and further our understanding of its clinical implications.

Appropriate Vestibular Stimulation in Children and Adolescents-A Prerequisite for Normal Cognitive, Motor Development and Bodily Homeostasis-A Review

The structural development of the vestibular part of the inner ear is completed by birth but its central connections continue to develop until adolescence. Their development is dependent on vestibular stimulation-vestibular experience. Studies have shown that vestibular function, modulated by experience and epigenetic factors, is not solely an instrument for body position regulation, navigation, and stabilization of the head and images but also influences cognition, emotion, the autonomous nervous system and hormones. To emphasize the importance of appropriate vestibular stimulation, we present a literature review of its effect on bodily homeostasis, cognition and emotion.

The construct validity and reliability of the Motor Development List for the assessment of motor skills in children with profound intellectual and multiple disabilities: The next step?

BACKGROUND

There are no psychometrically validated instruments available to measure motor skills of children with profound intellectual and multiple disabilities (PIMD). In this study, the construct validity and reliability (Rho) of the Motor Development List for children with PIMD (MDL-PIMD), a proxy-reported measure, was investigated.

METHODS

The MDL-PIMD was filled in by parents of 52 children with PIMD every six months over a period of two years. The items of the original MDL were categorised into subscales. A Mokken scale analysis for polytomous items was conducted for five subscales (Posture, Locomotion, Reaching, Grabbing and Facial Actions).

RESULTS

Several items were deleted to improve scalability. All scales showed good scalability (range scale H .66-.78) and reliability (range Rho .92-.98).

CONCLUSIONS

The MDL-PIMD seems to be a valid and reliable instrument for assessing the motor skills of children with PIMD, although more research is needed to confirm the factorial structure.

Impact of a Nutrient Formulation on Longitudinal Myelination, Cognition, and Behavior from Birth to 2 Years: A Randomized Clinical Trial

Observation studies suggest differences in myelination in relation to differences in early life nutrition. This two-center randomized controlled trial investigates the effect of a 12-month nutritional intervention on longitudinal changes in myelination, cognition, and behavior. Eighty-one full-term, neurotypical infants were randomized into an investigational (N = 42) or a control group (N = 39), receiving higher versus lower levels of a blend of nutrients. Non-randomized breastfed infants (N = 108) served as a reference group. Main outcomes were myelination (MRI), neurodevelopment (Bayley-III), social-emotional development (ASQ:SE-2), infant and toddler behavior (IBQ-R and TBAQ), and infant sleep (BISQ) during the first 2 years of life. The full analysis set comprised N = 67 infants from the randomized groups, with 81 myelin-sensitive MRI sequences. Significantly higher myelination was observed in the investigational compared to the control group at 6, 12, 18, and 24 months of life, as well as significantly higher gray matter volume at 24 months, a reduced number of night awakenings at 6 months, increased day sleep at 12 months, and reduced social fearfulness at 24 months. The results suggest that brain development may be modifiable with brain- and age-relevant nutritional approaches in healthy infants and young children, which may be foundational for later learning outcomes.

Parental Perception of Remote Education in Pandemic: An Analysis Based on Children's Cognitive Performance

The COVID-19 pandemic significantly changed patterns of human interaction, including in the educational sector, which was forced to transform relationships among students, families, and the academic community. The present study sought to establish the interrelationships between performance on cognitive tests during the preschool stage and the perceptions of parents about remote education in school children during the pandemic. The study included 100 preschool children from socially vulnerable sectors who underwent remote and distance learning in 2020 and 2021. The reliability of the applied questionnaire was determined through a confirmatory factor analysis. A structural equation model was constructed to determine the perceptions of parents about remote education based on cognitive performance during the preschool stage. The model fit yielded favorable results for predictive variables (χ2 = 7.734, DF = 9 [p = 0.561], the comparative goodness-of-fit index [CFI] = 1.000, root mean square error of approximation [RMSEA] = 0.000, standardized mean square residual [SRMR] = 0.069), and executive function (χ2 = 3.711, DF = 5 [p > 0.592], CFI = 1.000, RMSEA = 0.000, SRMR = 0.039) as latent variables that affected parents' perceptions. These results indicate that parents' perceptions of remote education are mediated by predictive aspects of learning and executive function during the preschool stage.

Motor control and skill acquisition in pediatric physical therapy: an enactive proposal

Theories of motor control and skill acquisition strongly influence and guide various fields of clinical practice. In last decades, changes in theoretical frameworks related to the conceptualization of brain plasticity, functional structures within the child, and environment have led to a revision of therapy approaches progressing from therapist-driven to child-initiated approaches. Even though theoretical frameworks and clinical practice are closely linked to the child's body, the profession has paid less attention to theories concerning the body's role and status in interpersonal relationships when fostering motor control and skill acquisition in children. In this theoretical paper we discuss the theoretical frameworks of motor control and skill acquisition that currently guide clinical practice. Through highlighting valuable contributions of these theories, we explore theoretical and practical benefits pediatric physical therapy can acquire by taking an enactive approach as a means to bring the child as a subject into focus. We rely on enactive concepts of embodiment, autonomy, and participatory sense-making in our exploration to provide an extended understanding of motor control and skill acquisition shaping our beliefs about what counts in therapeutic encounters in pediatric physical therapy.

Skeletal muscle fibre morphology in childhood-insights into myopenia in pediatric liver disease

TAKE-HOME MESSAGE

Skeletal muscle morphology in healthy children changes with age. Liver disease may preferentially affect type II fibres in adults with end-stage liver disease (ESLD). More research is needed on the effects of ESLD on muscle morphology in children.

Optimising motor development in the hospitalised infant with CHD: factors contributing to early motor challenges and recommendations for assessment and intervention

BACKGROUND

Neurodevelopmental challenges are the most prevalent comorbidity associated with a diagnosis of critical CHD, and there is a high incidence of gross and fine motor delays noted in early infancy. The frequency of motor delays in hospitalised infants with critical CHD requires close monitoring from developmental therapies (physical therapists, occupational therapists, and speech-language pathologists) to optimise motor development. Currently, minimal literature defines developmental therapists' role in caring for infants with critical CHD in intensive or acute care hospital units.

PURPOSE

This article describes typical infant motor skill development, how the hospital environment and events surrounding early cardiac surgical interventions impact those skills, and how developmental therapists support motor skill acquisition in infants with critical CHD. Recommendations for healthcare professionals and those who provide medical or developmental support in promotion of optimal motor skill development in hospitalised infants with critical CHD are discussed.

CONCLUSIONS

Infants with critical CHD requiring neonatal surgical intervention experience interrupted motor skill interactions and developmental trajectories. As part of the interdisciplinary team working in intensive and acute care settings, developmental therapists assess, guide motor intervention, promote optimal motor skill acquisition, and support the infant's overall development.

Development of integrated jaw-neck motor function in children at 6, 10 and 13 years of age compared to adults: A kinematic longitudinal study

BACKGROUND

The functional integration of the jaw and neck motor systems, of great importance to everyday oral activities, is established in early childhood. Detailed characterisation of this developmental progress is largely unknown.

OBJECTIVE

To establish developmental changes in jaw-neck motor function in children over the ages 6-13 years compared to adults.

METHODS

Jaw and head movement kinematics during jaw opening-closing and chewing were longitudinally recorded in 20 Swedish children (8 girls) at 6 (6.3 ± 0.4), 10 (10.3 ± 0.3) and 13 (13.5 ± 0.7) years of age and 20 adults (9 women, 28.2 ± 6.7). Movement amplitudes, jaw movement cycle time (CT), coefficient of variation (CV) and head/jaw ratio for amplitudes were analysed. Linear mixed effect analysis and Welch's t-test were used.

RESULTS

Children showed pronounced movement variability and longer CT at 6 and 10 years old during opening and chewing (p < .001). Compared to adults, 6-year-olds showed higher head/jaw ratios (p < .02) and longer CT (p < .001) during opening and chewing, and higher CV-head (p < .001) during chewing. Whereas 10-year-olds showed larger jaw and head amplitudes (p < .02) and longer CT (p < .001) during opening, and longer CT (p < .001) and higher CV-head (p < .001) during chewing. For 13-year-olds, longer CT (p < .001) during chewing was found.

CONCLUSION

Children showed pronounced movement variability and longer movement cycle time at 6-10 years and developmental progress in jaw-neck integration from 6 to 13 years, with 13-year-olds displaying adult-like movements. These results add new detailed understanding to the typical development of integrated jaw-neck motor function.

Nipple properties affect sensorimotor integration during bottle feeding in an infant pig model

Infant feeding is a critical neurological milestone in development defined by the coordination of muscles, peripheral nerves, and brainstem nuclei. In infants, milk flow rate is often limited to improve feeding performance without treating the underlying deficiencies in the sucking and swallowing processes. Modification of the neuromotor response via sensory information from the nipple during bottle feeding is an unexplored avenue for physiology-based interventions. In this study, we assessed how differences in nipple hole size and nipple stiffness affect sucking muscle activation and subsequent movement. We fabricated four bottle nipples of varying hole size and stiffness to determine how variation in nipple properties affects the sucking behavior of infant pigs. Our results demonstrate that sensory information from the nipple affects sucking motor output. Nipple hole sizes and stiffnesses with a larger milk flow rate resulted in greater muscle activity and kinematic movement. Additionally, our results suggest that sensorimotor interventions are better directed toward modulating tongue function rather than the mandible movements due to a greater response to sensory information. Understanding how sensory information influences infant feeding is instrumental in promoting effective infant feeding.

Effects of social and sensory deprivation in newborns: A lesson from the Covid-19 experience

BACKGROUND

Infancy is a complex period of human life, in which environmental experiences have a fundamental role for neurodevelopment. Although conditions of social and sensory deprivation are uncommon in high income countries, the Covid-19 pandemic abruptly modified this condition, by depriving people of their social stimuli of daily life.

AIM

To understand the impact of this deprivation on infants' behaviour, we investigated the short-term effects of isolation and use of individual protective systems by mothers during the first two weeks of life.

METHODS

The study included 11 mother-infant dyads with mothers tested positive to SARS-CoV-2 at the time of delivery (Covid group) and 11 dyads with a SARS-CoV-2 negative mother as controls. Neurobehavioral, visual, and sensory processing assessments were performed from birth to 3 months of age.

RESULTS

Findings showed the effect of deprivation on some neurobehavioral abilities of infants in the Covid group; in addition, differences in sensory maturation trends were observed, although they tended to gradually decrease until disappearance at 3 months of age.

CONCLUSION

These findings suggest the significant effects of early sensory and social deprivation during the first two weeks of life, but also provide several insights on the ability of the brain to restore its aptitudes by deleting or reducing the effects of early deprivation before the critical periods' closure.