Neural substrate and clinical significance of general movements: an update

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.

Reduction in limb-movement complexity at term-equivalent age is associated with motor developmental delay in very-preterm or very-low-birth-weight infants

Reduced complexity during the writhing period can be crucial in the spontaneous movements of high-risk infants for neurologic impairment. This study aimed to verify the association between quantified complexity of upper and lower-limb movements at term-equivalent age and motor development in very-preterm or very-low-birth-weight infants. Video images of spontaneous movements at term-equivalent age were collected from very-preterm or very-low-birth-weight infants. A pretrained pose-estimation model and sample entropy (SE) quantified the complexity of the upper- and lower-limb movements. Motor development was evaluated at 9 months of corrected age using Bayley Scales of Infant and Toddler Development, Third Edition. The SE measures were compared between infants with and without motor developmental delay (MDD). Among 90 infants, 11 exhibited MDD. SE measures at most of the upper and lower limbs were significantly reduced in infants with MDD compared to those without MDD (p < 0.05). Composite scores in the motor domain showed significant positive correlations with SE measures at most upper and lower limbs (p < 0.05). The results show that limb-movement complexity at term-equivalent age is reduced in infants with MDD at 9 months of corrected age. SE of limb movements can be a potentially useful kinematic parameter to detect high-risk infants for MDD.

Early Intervention Guided by the General Movements Examination at Term Corrected Age-Short Term Outcomes

BACKGROUND AND AIM

The early identification of the former premature neonates at risk of neurologic sequelae could lead to early intervention and a better prognosis. This pilot study aimed to investigate whether the General Movement patterns observed at term-equivalent age in former premature infants could serve as predictors for guiding early intervention and improving prognosis.

MATERIALS AND METHODS

In a population of 44 premature neonates (mean gestational age 33.59 weeks (+2.43 weeks)) examined at term-equivalent age, 10 neonates with a cramped-synchronized General Movements motor pattern were identified. These neonates were included in an early intervention program consisting of physiotherapy executed both by the therapist and by the parents at home. They were again examined at a corrected age of 12 weeks. The presence or absence of fidgety movements and the MOS-R (motor optimality score revised) was noted. The examinations were performed by certified specialists.

RESULTS

Normal fidgety movements and a MOS-R of 20-24 were presented in 9/10 of the former premature infants, with normal foot to foot contact present in 7/10, and normal hand to hand contact present in 5/10. The atypical patterns noted were side to side movements of the head in 5/10, a non-centered head in 9/10, asymmetric tonic neck reflex in 9/10 and jerky movements in 10/10. One patient presented with no fidgety movements and a MOS-R score of 9.

CONCLUSION

Early intervention in our group of patients allowed for an improvement in the neurologic status, demonstrated by the presence of fidgety movements. We suggest that early intervention should be indicated in all premature infants that present with a cramped-synchronized GM pattern during examination at term-equivalent age. However, due to the small sample size, the absence of statistical analysis and a control group, and the limited follow-up period, the conclusions must be approached with caution.

Longitudinal trajectory of medial gastrocnemius muscle growth in the first years of life

AIM

To define the longitudinal trajectory of gastrocnemius muscle growth in 6- to 36-month-old children with and without spastic cerebral palsy (SCP) and to compare trajectories by levels of gross motor function (Gross Motor Function Classification System, GMFCS) and presumed brain-lesion timing.

METHOD

Twenty typically developing children and 24 children with SCP (GMFCS levels I-II/III-IV = 15/9), were included (28/16 females/males; mean age at first scan 15.4 months [standard deviation 4.93, range 6.24-23.8]). Three-dimensional freehand ultrasound was used to repeatedly assess muscle volume, length, and cross-sectional area (CSA), resulting in 138 assessments (mean interval 7.9 months). Brain lesion timing was evaluated with magnetic resonance imaging classification. Linear mixed-effects models defined growth rates, adjusted for GMFCS levels and presumed brain-lesion timing.

RESULTS

At age 12 months, children with SCP showed smaller morphological muscle size than typically developing children (5.8 mL vs 9.8 mL, p < 0.001), while subsequently no differences in muscle growth were found between children with and without SCP (muscle volume: 0.65 mL/month vs 0.74 mL/month). However, muscle volume and CSA growth rates were lower in children classified in GMFCS levels III and IV than typically developing children and those classified in GMFCS levels I and II, with differences ranging from -56% to -70% (p < 0.001).

INTERPRETATION

Muscle growth is already hampered during infancy in SCP. Muscle size growth further reduces with decreasing functional levels, independently from the brain lesion. Early monitoring of muscle growth combined with early intervention is needed.

Predictive value of the General Movements Assessment and Standardized Infant NeuroDevelopmental Assessment in infants at high risk of neurodevelopmental disorders

AIM

To compare the predictive values of the General Movements Assessment (GMA) and the Standardized Infant NeuroDevelopmental Assessment (SINDA) neurological scale for atypical neurodevelopmental outcome in 3-month-old at-risk infants.

METHOD

A total of 109 infants (gestational age 30 weeks; range: 24-41; 52 males) attending a non-academic outpatient clinic were assessed with the GMA and the SINDA at 3 (2-4) months corrected age. The GMA pays attention to the complexity of general movements and presence of fidgety movements. Atypical neurodevelopmental outcome at 24 months corrected age (and older) implied cerebral palsy (CP) or a Bayley Mental Development Index or Bayley Psychomotor Development Index lower than 70.

RESULTS

At 24 months corrected (and older) age, 16 children had an atypical outcome, including 14 children with CP. Regarding markedly reduced general movement complexity in combination with absent or sporadic fidgety movements, the GMA predicted an atypical outcome with specificity, positive, and negative predictive values greater than 0.900, and sensitivity of 0.687 (95% confidence interval [CI] = 0.460-0.915). SINDA predicted an atypical outcome with sensitivity, specificity, and negative predictive value greater than 0.900 and a positive predictive value of 0.652 (95% CI = 0.457-0.847). Regarding absent fidgety movements only or markedly reduced general movement complexity, the GMA predicted the outcome less well than both general movement criteria.

INTERPRETATION

The SINDA and GMA both predict neurodevelopmental outcome well, but SINDA is easier to learn than the GMA; being a non-video-based assessment, it allows caregiver feedback during the consultation whereas the GMA usually does not.

Are sucking patterns and early spontaneous movements related to later developmental functioning outcomes? A cohort study

Sucking patterns and early spontaneous movements have an important role in the determination of later developmental problems, but the relationship of the two together with long-term outcomes has not been investigated. The objectives of this study were to (i) examine the relationship between sucking patterns using the Neonatal Oral Motor Assessment Scale (NOMAS) and fidgety movements and other movement patterns using detailed General Movements Assessment (GMA), and (ii) investigate the relationship between these early assessment methods and developmental functioning outcomes at later ages. We analyzed the NOMAS from 34 weeks' postmenstrual age up to 10 weeks post-term and GMA between 9 and 20 weeks post-term age, and the Bayley Scales of Infant and Toddler Development-Third Edition (Bayley-III) was applied for the developmental functioning outcomes to 62 infants (61%, 62/102) between 12 and 42 months of age. Among 102 infants at-risk, 70 (69%) showed a normal sucking pattern, and 85 (83%) had fidgety movements. The median Motor Optimality Score-Revised (MOS-R), as determined by GMA, of all infants was 24. The NOMAS was related to the MOS-R and its subcategories (p < 0.05) in all infants at-risk. The NOMAS, MOS-R and its subcategories were also related to cognitive, language, and motor development at later ages according to Bayley-III (p < 0.05).   Conclusion: This longitudinal study showed that the quality of sucking patterns, fidgety movements, and MOS-R were related to later developmental functioning, indicating that abnormal sucking patterns, aberrant fidgety movements, and lower MOS-R might predict developmental disorders. What is Known: • Sucking patterns and early spontaneous movements in which central pattern generators play an important role are related. • Sucking patterns and early spontaneous movements might be used separately to predict developmental outcomes. What is New: • Sucking patterns and early spontaneous movements, when used together, were related to later developmental functioning, including cognitive, language, and motor development in at-risk infants. • Predictive value of sucking patterns was lower for each developmental functioning outcome than early spontaneous movements.

Predictive value of General Movements Assessment for developmental delay at 18 months in children with complex congenital heart disease

BACKGROUND

Infants with complex congenital heart disease are at increased risk of impaired fetal brain growth, brain injury, and developmental impairments. The General Movement Assessment (GMA) is a valid and reliable tool to predict cerebral palsy (CP), especially in preterm infants. Predictive properties of the GMA in infants with complex congenital heart disease (CCHD) are unknown.

AIM

To evaluate predictive properties of the GMA to predict developmental outcomes, including cerebral palsy (CP), at 18-months corrected age (CA) in children with CCHD undergoing heart surgery in the first month of life.

METHODS

A prospective cohort of 56 infants with CCHD (35 males, 21 females) was assessed with GMA at writhing age (0-6 weeks CA) and fidgety age (7-17 weeks CA) and the Bayley Scales of Infant Development at 18 months. GMA focused on markedly reduced GM-variation and complexity (definitely abnormal (DA) GM-complexity) and fidgety movements. Predictive values of GMA for specific cognitive, language and motor delay (composite scores <85th percentile) and general developmental delay (delay in all domains) were calculated at 18 months.

RESULTS

At fidgety age, all infants had fidgety movements and no child was diagnosed with CP. DA GM-complexity at fidgety age predicted general developmental delay at 18 months (71 % sensitivity, 90 % specificity), but predicted specific developmental delay less robustly. DA GM-complexity at writhing age did not predict developmental delay, nor did it improve prediction based on DA GM-complexity at fidgety age.

CONCLUSIONS

In infants with CCHD and fidgety movements, DA GM-complexity at fidgety age predicted general developmental delay.

Correlations between Head Ultrasounds Performed at Term-Equivalent Age in Premature Neonates and General Movements Neurologic Examination Patterns

BACKGROUND AND AIM

Our research aims to find correlations between the brain imaging performed at term-corrected age and the atypical general movement (GM) patterns noticed during the same visit a-cramped-synchronized (CS) or poor repertoire (PR)-in formerly premature neonates to provide evidence for the structures involved in the modulation of GM patterns that could be injured and result in the appearance of these patterns and further deficits.

MATERIALS AND METHODS

A total of 44 preterm neonates ((mean GA, 33.59 weeks (+2.43 weeks)) were examined in the follow-up program at Life Memorial Hospital Bucharest at term-equivalent age (TEA). The GM and ultrasound examinations were performed by trained and certified specialists. Three GM pattens were noted (normal, PR, or CS), and the measurements of the following cerebral structures were conducted via head ultrasounds: ventricular index, the short and long axes of the lateral ventricles, the midbody distance of the lateral ventricle, the diagonal of the caudate nucleus, the width of the basal ganglia, the width of the interhemispheric fissure, the sinocortical width, the length and thickness of the callosal body, the anteroposterior diameter of the pons, the diameter of the vermis, and the transverse diameters of the cerebellum and vermis. The ultrasound measurements were compared between the groups in order to find statistically significant correlations by using the FANOVA test (significance p < 0.05).

RESULTS

The presence of the CS movement pattern was significantly associated with an increased ventricular index (mean 11.36 vs. 8.90; p = 0.032), increased midbody distance of the lateral ventricle-CS versus PR (8.31 vs. 3.73; p = 0.001); CS versus normal (8.31 vs. 3.34; p = 0.001), increased long and short axes of the lateral ventricles (p < 0.001), and decreased width of the basal ganglia-CS versus PR (11.07 vs. 15.69; p = 0.001); CS versus normal pattern (11.07 vs. 15.15; p = 0.0010). The PR movement pattern was significantly associated with an increased value of the sinocortical width when compared to the CS pattern (p < 0.001) and a decreased anteroposterior diameter of the pons when compared to both the CS (12.06 vs. 16.83; p = 0.001) and normal (12.06 vs. 16.78; p = 0.001) patterns. The same correlations were present when the subgroup of infants with a GA ≤ 32 weeks was analyzed.

CONCLUSIONS

Our study demonstrated that there are correlations between atypical GM patterns (cramped-synchronized-CS and poor repertoire-PR) and abnormalities in the dimensions of the structures measured via ultrasound at the term-equivalent age. The correlations could provide information about the structures that are affected and could lead to a lack of modulation in the GM patterns.

Spontaneous movements as prognostic tool of neurodevelopmental outcomes in preterm infants: a narrative review

An estimated 15 million infants are born prematurely each year. Although the survival rate of preterm infants has increased with advances in perinatal and neonatal care, many still experience various complications. Since improving the neurodevelopmental outcomes of preterm births is a crucial topic, accurate evaluations should be performed to detect infants at high risk of cerebral palsy. General movements are spontaneous movements involving the whole body as the expression of neural activity and can be an excellent biomarker of neural dysfunction caused by brain impairment in preterm infants. The predictive value of general movements with respect to cerebral palsy increases with continuous observation. Automated approaches to examining general movements based on machine learning can help overcome the limited utilization of assessment tools owing to their qualitative or semiquantitative nature and high dependence on assessor skills and experience. This review covers each of these topics by summarizing normal and abnormal general movements as well as recent advances in automatic approaches based on infantile spontaneous movements.

Associations between mother's depressive symptoms during pregnancy and newborn's brain functional connectivity

Depression during pregnancy is common and the prevalence further increased during the COVID pandemic. Recent findings have shown potential impact of antenatal depression on children's neurodevelopment and behavior, but the underlying mechanisms are unclear. Nor is it clear whether mild depressive symptoms among pregnant women would impact the developing brain. In this study, 40 healthy pregnant women had their depressive symptoms evaluated by the Beck Depression Inventory-II at ~12, ~24, and ~36 weeks of pregnancy, and their healthy full-term newborns underwent a brain MRI without sedation including resting-state fMRI for evaluation of functional connectivity development. The relationships between functional connectivities and maternal Beck Depression Inventory-II scores were evaluated by Spearman's rank partial correlation tests using appropriate multiple comparison correction with newborn's gender and gestational age at birth controlled. Significant negative correlations were identified between neonatal brain functional connectivity and mother's Beck Depression Inventory-II scores in the third trimester, but not in the first or second trimester. Higher depressive symptoms during the third trimester of pregnancy were associated with lower neonatal brain functional connectivity in the frontal lobe and between frontal/temporal lobe and occipital lobe, indicating a potential impact of maternal depressive symptoms on offspring brain development, even in the absence of clinical depression.

Mean 3D Dispersion for Automatic General Movement Assessment of Preterm Infants

The General Movement assessment (GMA) is a validated assessment of brain maturation primarily based on the qualitative analysis of the complexity and the variation of spontaneous motor activity. The GMA can identify preterm infants presenting an early abnormal developmental trajectory before term-equivalent age, which permits a personalized early developmental intervention. However, GMA is time-consuming and relies on a qualitative analysis; these limitations restrict the implementation of GMA in clinical practice. In this study based on a validated dataset of 183 videos from 92 premature infants (54 males, 38 females) born <33 weeks of gestational age (GA) and acquired between 32 and 40 weeks of GA, we introduce the mean 3D dispersion (M3D) for objective quantification and classification of normal and abnormal GMA. Moreover, we have created a new 3D representation of skeleton joints which allows an objective comparison of spontaneous movements of infants of different ages and sizes. Preterm infants with normal versus abnormal GMA had a distinct M3D distribution (p <0.001). The M3D has shown a good classification performance for GMA (AUC=0.7723) and presented an accuracy of 74.1%, a sensitivity of 75.8%, and a specificity of 70.1% when using an M3D of 0.29 as a classification threshold.Clinical relevance- Our study paves the way for the development of quantitative analysis of GMA within the Neonatal Unit.

Deep-Learning Markerless Tracking of Infant General Movements using Standard Video Recordings

Monitoring spontaneous General Movements (GM) of infants 6-20 weeks post-term age is a reliable tool to assess the quality of neurodevelopment in early infancy. Abnormal or absent GMs are reliable prognostic indicators of whether an infant is at risk of developing neurological impairments and disorders such as cerebral palsy (CP). Therapeutic interventions are most effective at improving neuromuscular outcomes if administered in early infancy. Current clinical protocols require trained assessors to rate videos of infant movements, a time-intensive task. This work proposes a simple, inexpensive, and broadly applicable markerless pose-estimation approach for automatic infant movement tracking using conventional video recordings from handheld devices (e.g., tablets and mobile phones). We leverage the enhanced capabilities of deep-learning technology in image processing to identify 12 anatomical locations (3 per limb) in each video frame, tracking a baby's natural movement throughout the recordings. We validate the capability of resnet152 and a mobile-net-v2-1 to identify body-parts in unseen frames from a full-term male infant, using a novel automatic unsupervised approach that fuses likelihood outputs of a Kalman filter and the deep-nets. Both deep-net models were found to perform very well in the identification of anatomical locations in the unseen data with high average Percentage of Correct Keypoints (aPCK) performances of >99.65% across all locations.Clinical relevance-Results of this research confirm the feasibility of a low-cost and publicly accessible technology to automatically track infants' GMs and diagnose those at higher risk of developing neurological conditions early, when clinical interventions are most effective.

Different intrauterine environments and children motor development in the first 6 months of life: a prospective longitudinal cohort

This prospective cohort longitudinal study examines the risk factors associated with different intrauterine environments and the influence of different intrauterine environments on children's motor development at 3- and 6-months of life. Participants were 346 mother/newborn dyads enrolled in the first 24 to 48 h after delivery in public hospitals. Four groups with no concurrent condition composed the sample: mothers with a clinical diagnosis of diabetes, mothers with newborns small for gestational age due to idiopathic intrauterine growth restriction (IUGR), mothers who smoked tobacco during gestation, and a control group composed of mothers without clinical condition. Children were assessed at three- and six-months regarding motor development, weight, length, head circumference, and parents completed a socioeconomic questionnaire. The IUGR children had lower supine, sitting, and overall gross motor scores at 6 months than the other children's groups. Anthropometric and sociodemographic characteristics negatively influenced gross motor development. IUGR and anthropometric and sociodemographic characteristics negatively impact motor development. Intrauterine environment impact child neurodevelopment.

Muscle Activity during Passive and Active Movements in Preterm and Full-Term Infants

Manifestation of muscle reactions at an early developmental stage may reflect the processes underlying the generation of appropriate muscle tone, which is also an integral part of all movements. In preterm infants, some aspects of muscular development may occur differently than in infants born at term. Here we evaluated early manifestations of muscle tone by measuring muscle responses to passive stretching (StR) and shortening (ShR) in both upper and lower limbs in preterm infants (at the corrected age from 0 weeks to 12 months), and compared them to those reported in our previous study on full-term infants. In a subgroup of participants, we also assessed spontaneous muscle activity during episodes of relatively large limb movements. The results showed very frequent StR and ShR, and also responses in muscles not being primarily stretched/shortened, in both preterm and full-term infants. A reduction of sensorimotor responses to muscle lengthening and shortening with age suggests a reduction in excitability and/or the acquisition of functionally appropriate muscle tone during the first year of life. The alterations of responses during passive and active movements in preterm infants were primarily seen in the early months, perhaps reflecting temporal changes in the excitability of the sensorimotor networks.

Dynamical systems model of development of the action differentiation in early infancy: a requisite of physical agency

Young infants are sensitive to whether their body movements cause subsequent events or not during the interaction with the environment. This ability has been revealed by empirical studies on the reinforcement of limb movements when a string is attached between an infant limb and a mobile toy suspended overhead. A previous study reproduced the experimental observation by modeling both the infant's limb and a mobile toy as a system of coupled oscillators. The authors then argued that emergence of agency could be explained by a phase transition in the dynamical system: from a weakly coupled state to a state where the both movements of the limb and the toy are highly coordinated. However, what remains unexplained is the following experimental observation: When the limb is connected to the mobile toy by a string, the infant increases the average velocity of the arm's movement. On the other hand, when the toy is controlled externally, the average arm's velocity is greatly reduced. Since young infants produce exuberant spontaneous movements even with no external stimuli, the inhibition of motor action to suppress the formation of spurious action-perception coupling should be also a crucial sign for the emergence of agency. Thus, we present a dynamical system model for the development of action differentiation, to move or not to move, in the mobile task. In addition to the pair of limb and mobile oscillators for providing positive feedback for reinforcement in the previous model, bifurcation dynamics are incorporated to enhance or inhibit self-movements in response to detecting contingencies between the limb and mobile movements. The results from computer simulations reproduce experimental observations on the developmental emergence of action differentiation between 2 and 3 months of age in the form of a bifurcation diagram. We infer that the emergence of physical agency entails young infants' ability not only to enhance a specific action-perception coupling, but also to decouple it and create a new mode of action-perception coupling based on the internal state dynamics with contingency detection between self-generated actions and environmental events.

Early detection of developmental delay in infants born very preterm or with very low birthweight

AIM

This study aimed to identify early clinical biomarkers from birth to 16 weeks corrected age to predict typical outcome and developmental delay in infants born very preterm or with very low birthweight.

METHOD

A prospective cohort of infants on the Sunshine Coast, Australia, was assessed using the Premie-Neuro Examination, the General Movement Assessment (GMA), the Alberta Infant Motor Scale, and the Infant Sensory Profile 2. At 24 months corrected age, delay was identified using the Bayley Scales of Infant and Toddler Development, Third Edition (Bayley-III) and Neurosensory Motor Developmental Assessment (NSMDA).

RESULTS

One hundred and four infants were recruited; 79 completed outcome assessments (43 females, 36 males; mean gestational age 30 weeks [SD 1 week 6 days], mean birthweight 1346 g [SD 323]). The incidence of developmental delay (motor or cognitive) was 6.3%. Suboptimal quality of fidgety general movements (temporal organization) at 16 weeks corrected age demonstrated the best predictive accuracy (Bayley-III motor: sensitivity 100% [95% confidence interval {CI} 3-100], specificity 75% [95% CI 63-84], area under the curve [AUC] 0.87); Bayley-III cognitive: sensitivity 100% [95% CI 3-100], specificity 75% [95% CI 64-84], AUC 0.88); NSMDA motor: sensitivity 100% [95% CI 40-100], specificity 81% [95% CI 70-90], AUC 0.91 [95% CI 0.86-0.95]). GMA trajectories that combined abnormal writhing general movements at 4 to 5 weeks corrected age with suboptimal quality of fidgety movement at 16 weeks corrected age were strongly predictive of developmental delay, superior to all other clinical tools, and perinatal and demographic variables investigated (p = 0.01, Akaike information criterion method 18.79 [score corrected for small sample size], accounting for 93% of the cumulative weight).

INTERPRETATION

Only the GMA had sufficient predictive validity to act as a biomarker for both conditions: typical outcome and developmental delay (motor or cognitive). GMA trajectories that assessed both writhing general movements at 4 to 5 weeks corrected age and quality of fidgety movement at 16 weeks corrected age predicted adverse neurodevelopmental outcome, accurately differentiating between infants with typical outcomes and those at increased risk for motor or cognitive delay.

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.

Dendritic Spines: Synaptogenesis and Synaptic Pruning for the Developmental Organization of Brain Circuits

Synaptic overproduction and elimination is a regular developmental event in the mammalian brain. In the cerebral cortex, synaptic overproduction is almost exclusively correlated with glutamatergic synapses located on dendritic spines. Therefore, analysis of changes in spine density on different parts of the dendritic tree in identified classes of principal neurons could provide insight into developmental reorganization of specific microcircuits.The activity-dependent stabilization and selective elimination of the initially overproduced synapses is a major mechanism for generating diversity of neural connections beyond their genetic determination. The largest number of overproduced synapses was found in the monkey and human cerebral cortex. The highest (exceeding adult values by two- to threefold) and most protracted overproduction (up to third decade of life) was described for associative layer IIIC pyramidal neurons in the human dorsolateral prefrontal cortex.Therefore, the highest proportion and extraordinarily extended phase of synaptic spine overproduction is a hallmark of neural circuitry in human higher-order associative areas. This indicates that microcircuits processing the most complex human cognitive functions have the highest level of developmental plasticity. This finding is the backbone for understanding the effect of environmental impact on the development of the most complex, human-specific cognitive and emotional capacities, and on the late onset of human-specific neuropsychiatric disorders, such as autism and schizophrenia.

The fetal pain paradox

Controversy exists as to when conscious pain perception in the fetus may begin. According to the hypothesis of cortical necessity, thalamocortical connections, which do not form until after 24-28 weeks gestation, are necessary for conscious pain perception. However, anesthesiologists and neonatologists treat age-matched neonates as both conscious and pain-capable due to observable and measurable behavioral, hormonal, and physiologic indicators of pain. In preterm infants, these multimodal indicators of pain are uncontroversial, and their presence, despite occurring prior to functional thalamocortical connections, has guided the use of analgesics in neonatology and fetal surgery for decades. However, some medical groups state that below 24 weeks gestation, there is no pain capacity. Thus, a paradox exists in the disparate acknowledgment of pain capability in overlapping patient populations. Brain networks vary by age. During the first and second trimesters, the cortical subplate, a unique structure that is present only during fetal and early neonatal development, forms the first cortical network. In the third trimester, the cortical plate assumes this function. According to the subplate modulation hypothesis, a network of connections to the subplate and subcortical structures is sufficient to facilitate conscious pain perception in the fetus and the preterm neonate prior to 24 weeks gestation. Therefore, similar to other fetal and neonatal systems that have a transitional phase (i.e., circulatory system), there is now strong evidence for transitional developmental phases of fetal and neonatal pain circuitry.

Going Beyond Conventional Assessment of Developmental Motor Disorders: Exploring Video Methods for Early Identification Among Children 0 to 3 Years

Motor skills and movement-related functioning significantly shape how children experience and interact with the world around them. Among infants and young children, developmental motor disorders contribute to delays with motor, cognitive, and psychosocial development. Early and accurate identification of these disorders is necessary to facilitate timely access to therapeutic interventions that minimize the long-term effects of disability on everyday activities and participation. In the United States, motor assessments commonly used among children 0 to 3 years focus on completion of specific motor skills at a single point in time, which provides only a part of the greater picture that is a child's motor and movement-related functioning. Video-capture methods, like the General Movements Assessment (GMA) and the Infant Motor Profile (IMP), offer greater accuracy and predictive power to (1) identify motor deficits in young children and (2) facilitate early access to supportive, therapeutic intervention.

Transient compartmentalization and accelerated volume growth coincide with the expected development of cortical afferents in the human neostriatum

The neostriatum plays a central role in cortico-subcortical circuitry underlying goal-directed behavior. The adult mammalian neostriatum shows chemical and cytoarchitectonic compartmentalization in line with the connectivity. However, it is poorly understood how and when fetal compartmentalization (AChE-rich islands, nonreactive matrix) switches to adult (AChE-poor striosomes, reactive matrix) and how this relates to the ingrowth of corticostriatal afferents. Here, we analyze neostriatal compartments on postmortem human brains from 9 postconceptional week (PCW) to 18 postnatal months (PM), using Nissl staining, histochemical techniques (AChE, PAS-Alcian), immunohistochemistry, stereology, and comparing data with volume-growth of in vivo and in vitro MRI. We find that compartmentalization (C) follows a two-compartment (2-C) pattern around 10PCW and is transformed into a midgestational labyrinth-like 3-C pattern (patches, AChE-nonreactive perimeters, matrix), peaking between 22 and 28PCW during accelerated volume-growth. Finally, compartmentalization resolves perinatally, by the decrease in transient "AChE-clumping," disappearance of AChE-nonreactive, ECM-rich perimeters, and an increase in matrix reactivity. The initial "mature" pattern appears around 9 PM. Therefore, transient, a 3-C pattern and accelerated neostriatal growth coincide with the expected timing of the nonhomogeneous distribution of corticostriatal afferents. The decrease in growth-related AChE activity and transfiguration of corticostriatal terminals are putative mechanisms underlying fetal compartments reorganization. Our findings serve as normative for studying neurodevelopmental disorders.

Clinical factors associated with abnormal general movements of preterm newborns during hospitalization in a neonatal intensive care unit

INTRODUCTION

There is no clarity about which clinical variables during hospitalization in the Neonatal Intensive Care Unit (NICU) are associated with abnormal General Movements (GMs).

OBJECTIVE

To describe the trajectory of GMs of preterm newborns and explore the association between clinical variables and the presence of abnormal GMs during the NICU stay.

METHODS

Fifty-eight preterm newborns (33 males), with a mean gestational age at birth of 31,93 week's postmenstrual age, were evaluated using the GMs assessment by Hadders-Algra method. Clinical variables recorded weekly throughout the hospitalization period. The weekly association between clinical variables and the presence of abnormal GMs was tested using the Generalized Estimating Equations (GEE) model.

RESULTS

Preterm infants were recorded for up to sixteen weeks and more than half of the infants (56.9 %) had abnormal movements in at least one week during hospitalization. The absence of peri-intraventricular hemorrhage (PIVH) grades I-II and non-invasive ventilatory support and/or oxygen therapy on the day of the evaluation reduced, respectively, by 77.3 % (OR = 0.23; p > 0.0001) and 64.3 % (OR = 0.36; p > 0.0001) the chance of having an abnormal classification. In addition, each day of increased invasive mechanical ventilation increased the chance of having an abnormal classification by 1.11 times (OR = 0.025; p > 0.0001).

CONCLUSION

PIVH grades I-II, longer durations of mechanical ventilation and the presence of non-invasive ventilatory support and/or oxygen therapy are associated with abnormal movements during stay in the neonatal period. The data suggest that development outcome of infants having these conditions should be closely monitored.

Emerging signs of autism spectrum disorder in infancy: Putative neural substrate

Autism spectrum disorder (ASD) is characterized by altered development of the social brain with prominent atypical features in the fronto-temporo-parietal cortex and cerebellum. Early signs of ASD emerge between 6 and 12 months: reduced social communication, slightly less advanced motor development, and repetitive behaviour. The fronto-temporo-parietal cortex and cerebellum play a prominent role in the development of social communication, whereas fronto-parietal-cerebellar networks are involved in the planning of movements, that is, movement selection. Atypical sensory responsivity, a core feature of ASD, may result in impaired development of social communication and motor skills and/or selection of atypical repetitive behaviour. In the first postnatal year, the brain areas involved are characterized by gradual dissolution of temporary structures: the fronto-temporo-parietal cortical subplate and cerebellar external granular layer. It is hypothesized that altered dissolution of the transient structures opens the window for the expression of early signs of ASD arising in the impaired developing permanent networks. WHAT THIS PAPER ADDS: The early social and motor signs of autism spectrum disorder emerge between the ages of 6 and 12 months. Altered dissolution of transient brain structures in the fronto-temporo-parietal cortex and cerebellum may underlie the emergence of these early signs.

The Importance of Monitoring Neurodevelopmental Outcomes for Preterm Infants: A Comparison of the AIMS, GMA, Pull to Sit Maneuver and ASQ-3

BACKGROUND

Clinicians and parents should closely monitor the neurodevelopment of very preterm infants. The aim of our study was to compare whether neurodevelopmental assessments completed by parents and those done by specialists yielded similar outcomes. We wanted to check whether the assessments completed by specialists and parents were comparable in outcomes to emphasize the important roles of early assessment of a child and of the parents in their child's treatment and medical care. Another aim was to check whether or not the pull to sit maneuver from the Neonatal Behavioral Assessment Scale (NBAS) is still a parable item in well-known scales of neurodevelopment.

METHODS

We assessed 18 preterm neonates in the fourth month of corrected age with scales such as the General Movement Assessment (GMA), the Alberta Infant Motor Scale (AIMS), and the pull to sit maneuver from the NBAS. Finally, we asked parents to complete the Ages and Stages Questionnaire, Third Edition (ASQ-3).

RESULTS

We found that the respective assessments completed by specialists and parents are comparable in outcomes. We also found that the pull to sit item from the NBAS was still a valid test since it showed similar findings to those from the AIMS, the GMA, and the ASQ-3.

CONCLUSIONS

The pull to sit item from the NBAS is an important item for assessment of very preterm infants. Specialists should also take into consideration the input and concerns of parents when planning for treatment and intervention.

Dynamics of changes in motor development depending on the quality in the 3rd month of life

The aim of the study was to show that the quantitative and qualitative motor development from the 3rd month of life is key to achieving milestones and that it may be an early warning signal in children at risk of cerebral palsy (CP). The study population included 93 children (69 born at term). Children were born at week 38 ± 4, the mean body weight was 3,102 ± 814 g. All children were evaluated after reaching the 3rd month of life (quantitative and qualitative assessment), and then the 4.5th, 7th, and 12th of life (quantitative assessment). In case of suspected CP, children were followed until the 18th month, when the diagnosis was confirmed. If at the age of 3 months, a child achieved a quadrangle of support and symmetrical support, then its development at the 4.5th month of life was correct, it would creep, and it would assume a crawl position, then in the final assessment (12th month of life), the child would start to walk. If a child failed to achieve a quadrangle of support and symmetrical support and the dynamics of its development were incorrect, the development would be delayed (12th month of life), or CP would develop. A correct qualitative assessment in the 3rd month of life with a high probability guarantees corrects quantitative development at the 4.5th, 7.5th, and 12th months of life. If the qualitative assessment in the 3rd month of life was very low the child would probably be diagnosed with CP at 18 months.

Infant motor behaviour and functional and cognitive outcome at school-age: A follow-up study in very high-risk children

BACKGROUND

The Infant Motor Profile (IMP) is an appropriate tool to assess and monitor infant motor behaviour over time. Infants at very high risk (VHR) due to a lesion of the brain generally show impaired motor development. They may grow into or out of their neurodevelopmental deficit.

AIMS

Evaluate associations between IMP-trajectories, summarised by IMP-scores in early infancy and rates of change, and functional and cognitive outcome at school-age in VHR-children.

STUDY DESIGN

Longitudinal study.

SUBJECTS

31 VHR-children, mainly due to a brain lesion, who had multiple IMP-assessments during infancy, were re-assessed at 7-10 years (school-age).

OUTCOME MEASURES

Functional outcome was assessed with the Vineland-II, cognition with RAKIT 2. Associations between IMP-trajectories and outcome were tested by multivariable linear regression analyses.

RESULTS

When corrected for sex, maternal education and follow-up age, initial scores of total IMP, variation and performance domains, as well as their rates of change were associated with better functional outcome (unstandardised coefficients [95% CI]): 36.44 [19.60-53.28], 33.46 [17.43-49.49], 16.52 [7.58-25.46], and 513.15 [262.51-763.79], 356.70 [148.24-565.15], and 269 [130.57-407.43], respectively. Positive rates of change in variation scores were associated with better cognition at school-age: 34.81 [16.58-53.03].

CONCLUSION

Our study indicated that in VHR-children IMP-trajectories were associated with functional outcome at school-age, and to a minor extent also with cognition. Initial IMP-scores presumably reflect the effect of an early brain lesion on brain functioning, whereas IMP rate of change reflects whether infants are able to grow into or out of their initial neurodevelopmental deficit.

Development and Validation of a Deep Learning Method to Predict Cerebral Palsy From Spontaneous Movements in Infants at High Risk

IMPORTANCE

Early identification of cerebral palsy (CP) is important for early intervention, yet expert-based assessments do not permit widespread use, and conventional machine learning alternatives lack validity.

OBJECTIVE

To develop and assess the external validity of a novel deep learning-based method to predict CP based on videos of infants' spontaneous movements at 9 to 18 weeks' corrected age.

DESIGN, SETTING, AND PARTICIPANTS

This prognostic study of a deep learning-based method to predict CP at a corrected age of 12 to 89 months involved 557 infants with a high risk of perinatal brain injury who were enrolled in previous studies conducted at 13 hospitals in Belgium, India, Norway, and the US between September 10, 2001, and October 25, 2018. Analysis was performed between February 11, 2020, and September 23, 2021. Included infants had available video recorded during the fidgety movement period from 9 to 18 weeks' corrected age, available classifications of fidgety movements ascertained by the general movement assessment (GMA) tool, and available data on CP status at 12 months' corrected age or older. A total of 418 infants (75.0%) were randomly assigned to the model development (training and internal validation) sample, and 139 (25.0%) were randomly assigned to the external validation sample (1 test set).

EXPOSURE

Video recording of spontaneous movements.

MAIN OUTCOMES AND MEASURES

The primary outcome was prediction of CP. Deep learning-based prediction of CP was performed automatically from a single video. Secondary outcomes included prediction of associated functional level and CP subtype. Sensitivity, specificity, positive and negative predictive values, and accuracy were assessed.

RESULTS

Among 557 infants (310 [55.7%] male), the median (IQR) corrected age was 12 (11-13) weeks at assessment, and 84 infants (15.1%) were diagnosed with CP at a mean (SD) age of 3.4 (1.7) years. Data on race and ethnicity were not reported because previous studies (from which the infant samples were derived) used different study protocols with inconsistent collection of these data. On external validation, the deep learning-based CP prediction method had sensitivity of 71.4% (95% CI, 47.8%-88.7%), specificity of 94.1% (95% CI, 88.2%-97.6%), positive predictive value of 68.2% (95% CI, 45.1%-86.1%), and negative predictive value of 94.9% (95% CI, 89.2%-98.1%). In comparison, the GMA tool had sensitivity of 70.0% (95% CI, 45.7%-88.1%), specificity of 88.7% (95% CI, 81.5%-93.8%), positive predictive value of 51.9% (95% CI, 32.0%-71.3%), and negative predictive value of 94.4% (95% CI, 88.3%-97.9%). The deep learning method achieved higher accuracy than the conventional machine learning method (90.6% [95% CI, 84.5%-94.9%] vs 72.7% [95% CI, 64.5%-79.9%]; P < .001), but no significant improvement in accuracy was observed compared with the GMA tool (85.9%; 95% CI, 78.9%-91.3%; P = .11). The deep learning prediction model had higher sensitivity among infants with nonambulatory CP (100%; 95% CI, 63.1%-100%) vs ambulatory CP (58.3%; 95% CI, 27.7%-84.8%; P = .02) and spastic bilateral CP (92.3%; 95% CI, 64.0%-99.8%) vs spastic unilateral CP (42.9%; 95% CI, 9.9%-81.6%; P < .001).

CONCLUSIONS AND RELEVANCE

In this prognostic study, a deep learning-based method for predicting CP at 9 to 18 weeks' corrected age had predictive accuracy on external validation, which suggests possible avenues for using deep learning-based software to provide objective early detection of CP in clinical settings.

Early motor behavior of infants exposed to maternal mental health disorders - A South African perspective

INTRODUCTION

Over the past five decades the bulk of research on exposure to maternal mental health disorders and infant neurodevelopment has been generated in high-income countries. The current study included infants, residing in low-income communities in South Africa, born to mothers with a history of psychiatric disorders.

AIM

To assess the motor behavior of 10- to 20-week-old infants exposed to maternal mental health disorders, and a subgroup of infants with prenatal psychotropic medication exposure.

METHODS

The present study is a cross-sectional descriptive study, with a longitudinal subgroup analysis. General Movement Assessment (GMA), including the Motor Optimality Score-Revised (MOS-R), was used at 10-20 weeks corrected age to assess infant motor behavior.

RESULTS

The study included 112 infants. No significant difference (p = 0.523) was found on the MOS-R between infants exposed to maternal mental health disorders (n = 70) and the comparison group (n = 42). Both the exposed and comparison groups scored within the mildly reduced range on the MOS-R. No significant differences were found in a subgroup of infants with prenatal exposure to multi-class psychotropic medication (n = 17), mono-class psychotropic medication (n = 35) or valproate exposure (n = 10) (p > 0.1).

CONCLUSION

No association was found between exposure to maternal mental health disorders or exposure to psychotropic medication and infant motor behavior at 10-20 weeks post-term age on the MOS-R. Future research should focus on the contribution of exposure to specific classes and types of psychotropic medication on neurodevelopmental outcome of infants in larger cohorts.

Muscle architecture, growth, and biological Remodelling in cerebral palsy: a narrative review

Cerebral palsy (CP) is caused by a static lesion to the brain occurring in utero or up to the first 2 years of life; it often manifests as musculoskeletal impairments and movement disorders including spasticity and contractures. Variable manifestation of the pathology across individuals, coupled with differing mechanics and treatments, leads to a heterogeneous collection of clinical phenotypes that affect muscles and individuals differently. Growth of muscles in CP deviates from typical development, evident as early as 15 months of age. Muscles in CP may be reduced in volume by as much as 40%, may be shorter in length, present longer tendons, and may have fewer sarcomeres in series that are overstretched compared to typical. Macroscale and functional deficits are likely mediated by dysfunction at the cellular level, which manifests as impaired growth. Within muscle fibres, satellite cells are decreased by as much as 40–70% and the regenerative capacity of remaining satellite cells appears compromised. Impaired muscle regeneration in CP is coupled with extracellular matrix expansion and increased pro-inflammatory gene expression; resultant muscles are smaller, stiffer, and weaker than typical muscle. These differences may contribute to individuals with CP participating in less physical activity, thus decreasing opportunities for mechanical loading, commencing a vicious cycle of muscle disuse and secondary sarcopenia. This narrative review describes the effects of CP on skeletal muscles encompassing substantive changes from whole muscle function to cell-level effects and the effects of common treatments. We discuss growth and mechanics of skeletal muscles in CP and propose areas where future work is needed to understand these interactions, particularly the link between neural insult and cell-level manifestation of CP.

Deep learning-based quantitative analyses of spontaneous movements and their association with early neurological development in preterm infants

This study aimed to develop quantitative assessments of spontaneous movements in high-risk preterm infants based on a deep learning algorithm. Video images of spontaneous movements were recorded in very preterm infants at the term-equivalent age. The Hammersmith Infant Neurological Examination (HINE) was performed in infants at 4 months of corrected age. Joint positional data were extracted using a pretrained pose-estimation model. Complexity and similarity indices of joint angle and angular velocity in terms of sample entropy and Pearson correlation coefficient were compared between the infants with HINE < 60 and ≥ 60. Video images of spontaneous movements were recorded in 65 preterm infants at term-equivalent age. Complexity indices of joint angles and angular velocities differed between the infants with HINE < 60 and ≥ 60 and correlated positively with HINE scores in most of the joints at the upper and lower extremities (p < 0.05). Similarity indices between each joint angle or joint angular velocity did not differ between the two groups in most of the joints at the upper and lower extremities. Quantitative assessments of spontaneous movements in preterm infants are feasible using a deep learning algorithm and sample entropy. The results indicated that complexity indices of joint movements at both the upper and lower extremities can be potential candidates for detecting developmental outcomes in preterm infants.

Development of functional organization within the sensorimotor network across the perinatal period

In the mature human brain, the neural processing related to different body parts is reflected in patterns of functional connectivity, which is strongest between functional homologs in opposite cortical hemispheres. To understand how this organization is first established, we investigated functional connectivity between limb regions in the sensorimotor cortex in 400 preterm and term infants aged across the equivalent period to the third trimester of gestation (32–45 weeks postmenstrual age). Masks were obtained from empirically derived functional responses in neonates from an independent data set. We demonstrate the early presence of a crude but spatially organized functional connectivity, that rapidly matures across the preterm period to achieve an adult‐like configuration by the normal time of birth. Specifically, connectivity was strongest between homolog regions, followed by connectivity between adjacent regions (different limbs but same hemisphere) already in the preterm brain, and increased with age. These changes were specific to the sensorimotor network. Crucially, these trajectories were strongly dependent on age more than age of birth. This demonstrates that during the perinatal period the sensorimotor cortex undergoes preprogrammed changes determining the functional movement organization that are not altered by preterm birth in absence of brain injury.

More Jump More Health: Vertical Jumping Learning of Chinese Children and Health Promotion

Vertical jumping is the most important of the fundamental motor skills and has an important impact on children's health. A systematic study was conducted on the influence of vertical jumping on children's health and motor development patterns. In this study, the training and learning of vertical jumping were found to be effective in promoting children's development, especially in terms of height and muscle growth. Training interventions were used to determine the influence of age on children's learning of the correct vertical jumping motor pattern. Sex was found to have no influence on children's learning of vertical jumping. Although children were found to be able to learn the correct vertical jumping motor pattern, they could not reach a level of proficiency and intuitively apply the acquired skills to task completion. Cognitive ability was found to have a crucial effect on motor learning among children, especially when they faced various task constraints.

The developing brain: Challenges and opportunities to promote school readiness in young children at risk of neurodevelopmental disorders in low- and middle-income countries

This paper discusses possibilities for early detection and early intervention in infants with or at increased risk of neurodevelopmental disorders in low- and middle-income countries (LMICs). The brain's high rate of developmental activity in the early years post-term challenges early detection. It also offers opportunities for early intervention and facilitation of school readiness. The paper proposes that in the first year post-term two early detection options are feasible for LMICs: (a) caregiver screening questionnaires that carry little costs but predict neurodevelopmental disorders only moderately well; (b) the Hammersmith Infant Neurological Examination and Standardized Infant NeuroDevelopmental Assessment (SINDA) which are easy tools that predict neurodisability well but require assessment by health professionals. The young brain's neuroplasticity offers great opportunities for early intervention. Ample evidence indicates that families play a critical role in early intervention of infants at increased risk of neurodevelopmental disorders. Other interventional key elements are responsive parenting and stimulation of infant development. The intervention's composition and delivery mode depend on the infant's risk profile. For instance, in infants with moderately increased risk (e.g., preterm infants) lay community health workers may provide major parts of intervention, whereas in children with neurodisability (e.g., cerebral palsy) health professionals play a larger role.

Early movement restriction deteriorates motor function and soleus muscle physiology

Children with low physical activity and interactions with environment experience atypical sensorimotor development and maturation leading to anatomical and functional disorganization of the sensorimotor circuitry and also to enduring altered motor function. Previous data have shown that postnatal movement restriction in rats results in locomotor disturbances, functional disorganization and hyperexcitability of the hind limb representations in the somatosensory and motor cortices, without apparent brain damage. Due to the reciprocal interplay between the nervous system and muscle, it is difficult to determine whether muscle alteration is the cause or the result of the altered sensorimotor behavior (Canu et al., 2019). In the present paper, our objectives were to evaluate the impact of early movement restriction leading to sensorimotor restriction (SMR) during development on the postural soleus muscle and on sensorimotor performance in rats, and to determine whether changes were reversed when typical activity was resumed. Rats were submitted to SMR by hind limb immobilization for 16 h / day from birth to postnatal day 28 (PND28). In situ isometric contractile properties of soleus muscle, fiber cross sectional area (CSA) and myosin heavy chain content (MHC) were studied at PND28 and PND60. In addition, the motor function was evaluated weekly from PND28 to PND60. At PND28, SMR rats presented a severe atrophy of soleus muscle, a decrease in CSA and a force loss. The muscle maturation appeared delayed, with persistence of neonatal forms of MHC. Changes in kinetic properties were moderate or absent. The Hoffmann reflex provided evidence for spinal hyperreflexia and signs of spasticity. Most changes were reversed at PND60, except muscle atrophy. Functional motor tests that require a good limb coordination, i.e. rotarod and locomotion, showed an enduring alteration related to SMR, even after one month of 'typical' activity. On the other hand, paw withdrawal test and grip test were poorly affected by SMR whereas spontaneous locomotor activity increased over time. Our results support the idea that proprioceptive feedback is at least as important as the amount of motor activity to promote a typical development of motor function. A better knowledge of the interplay between hypoactivity, muscle properties and central motor commands may offer therapeutic perspectives for children suffering from neurodevelopmental disorders.

Recording activity in proximal muscle networks with surface EMG in assessing infant motor development

OBJECTIVE

To develop methods for recording and analysing infant's proximal muscle activations.

METHODS

Surface electromyography (sEMG) of truncal muscles was recorded in three months old infants (N = 18) during spontaneous movement and controlled postural changes. The infants were also divided into two groups according to motor performance. We developed an efficient method for removing dynamic cardiac artefacts to allow i) accurate estimation of individual muscle activations, as well as ii) quantitative characterization of muscle networks.

RESULTS

The automated removal of cardiac artefacts allowed quantitation of truncal muscle activity, which showed predictable effects during postural changes, and there were differences between high and low performing infants.The muscle networks showed consistent change in network density during spontaneous movements between supine and prone position. Moreover, activity correlations in individual pairs of back muscles linked to infant́s motor performance.

CONCLUSIONS

The hereby developed sEMG analysis methodology is feasible and may disclose differences between high and low performing infants. Analysis of the muscle networks may provide novel insight to central control of motility.

SIGNIFICANCE

Quantitative analysis of infant's muscle activity and muscle networks holds promise for an objective neurodevelopmental assessment of motor system.

Global entrainment in the brain-body-environment: retrospective and prospective views

We celebrate the 60th anniversary of Biological Cybernetics. It has also been 30 years since "Self-organized control of bipedal locomotion by neural oscillators in unpredictable environment" was published in Biological Cybernetics (Taga et al. in Biol Cybern 65(3):147-159, 1991). I would like to look back on the creation of this paper and discuss its subsequent development and future perspectives.

Infant's Behaviour Checklist for low birth weight infants and later neurodevelopmental outcome

Assessment of the characteristics of spontaneous movements and behaviour in early infancy helps in estimating developmental outcomes. We introduced the Infant Behaviour Checklist (IBC) and examined the relationship between the behavioural characteristics of low-birth-weight infants and neurodevelopmental outcomes at 6 years of age. The behavioural characteristics during the neonatal (36-43 weeks, adjusted) and early infancy periods (49-60 weeks, adjusted) were assessed in very-low-birth-weight infants. The IBC includes 44 common behaviours. We assessed the appearance of individual behavioural characteristics at each period according to the neurodevelopmental outcome. Of the 143 infants assessed during the neonatal period, 89 had typical development (TD), 30 had intellectual disability (ID), and 24 had autism spectrum disorder (ASD). In 78 infants assessed during early infancy, 40, 21, and 17 had TD, ID, and ASD, respectively. The frequency of appearance of three behaviour-related items was significantly lower in the ID group than in the TD group. The frequency of appearance of three posture- and behaviour-related items was significantly lower, while that of two posture-related items was significantly higher, in the ASD group than in the TD group. Behavioural assessment using the IBC may provide promising clues when considering early intervention for low-birth-weight infants.

General movement assessment is correlated with neonatal behavior neurological assessment/cerebral magnetic resonance imaging in preterm infants

To explore the relationship between general movements (GMs) and neonatal behavior neurological assessment (NBNA)/cerebral magnetic resonance imaging (MRI) in preterm infants.Forty preterm infants were examined with GMs assessment before gestational age of 40 weeks; NBNA was performed at the age of 40 weeks; cerebral MRI was performed at the age of 42 weeks.Our experiment showed that preterm infants with poor GMs scores are more likely to have low NBNA scores (P = .001); preterm infants with abnormal cerebral MRI are more likely to have low NBNA scores (P = .002); preterm infants with poor GMs scores are more likely to have abnormal cerebral MRI (P = .012).GM assessment is correlated with NBNA and MRI results in preterm infants for neurological development.

Fundamentals of the Development of Connectivity in the Human Fetal Brain in Late Gestation: From 24 Weeks Gestational Age to Term

During the second half of gestation, the human cerebrum undergoes pivotal histogenetic events that underlie functional connectivity. These include the growth, guidance, selection of axonal pathways, and their first engagement in neuronal networks. Here, we characterize the spatiotemporal patterns of cerebral connectivity in extremely preterm (EPT), very preterm (VPT), preterm and term babies, focusing on magnetic resonance imaging (MRI) and histological data. In the EPT and VPT babies, thalamocortical axons enter into the cortical plate creating the electrical synapses. Additionally, the subplate zone gradually resolves in the preterm and term brain in conjunction with the growth of associative pathways leading to the activation of large-scale neural networks. We demonstrate that specific classes of axonal pathways within cerebral compartments are selectively vulnerable to temporally nested pathogenic factors. In particular, the radial distribution of axonal lesions, that is, radial vulnerability, is a robust predictor of clinical outcome. Furthermore, the subplate tangential nexus that we can visualize using MRI could be an additional marker as pivotal in the development of cortical connectivity. We suggest to direct future research toward the identification of sensitive markers of earlier lesions, the elucidation of genetic mechanisms underlying pathogenesis, and better long-term follow-up using structural and functional MRI.

Transient structural MRI patterns correlate with the motor functions in preterm infants

AIM

To explore the relationships between transient structural brain patterns on MRI at preterm and at term-equivalent age (TEA) as a predictor of general movements (GMs) and motor development at 1-year corrected age (CA) in very preterm infants.

METHODS

In this prospective study, 30 very preterm infants (median = 28wks; 16 males) had structural magnetic resonance imaging (MRI) at preterm (median = 31wks + 6d) and at TEA (median = 40wks) and neuromotor assessments. The quality of GMs was assessed by Prechtl's general movements assessment and a detailed analysis of the motor repertoire was performed by calculating a motor optimality score (MOS), both at term age and at 3 months post-term. Motor development at 1-year CA was evaluated with the Infant Motor Profile (IMP). Associations between qualitative MRI findings and neuromotor scores were investigated.

RESULTS

Abnormal GMs and low motor performance at 1-year CA were associated with the poor visibility of transient structural pattern, that is with sagittal strata.

INTERPRETATION

Transient structural MRI pattern, sagittal strata, at preterm age is related to the quality of GMs and later motor development in preterm infants. This transient fetal brain compartment may be considered as a component of neurobiological basis for early neuromotor behavior, as expressed by GMs.

Early Diagnostics and Early Intervention in Neurodevelopmental Disorders-Age-Dependent Challenges and Opportunities

This review discusses early diagnostics and early intervention in developmental disorders in the light of brain development. The best instruments for early detection of cerebral palsy (CP) with or without intellectual disability are neonatal magnetic resonance imaging, general movements assessment at 2-4 months and from 2-4 months onwards, the Hammersmith Infant Neurological Examination and Standardized Infant NeuroDevelopmental Assessment. Early detection of autism spectrum disorders (ASD) is difficult; its first signs emerge at the end of the first year. Prediction with the Modified Checklist for Autism in Toddlers and Infant Toddler Checklist is possible to some extent and improves during the second year, especially in children at familial risk of ASD. Thus, prediction improves substantially when transient brain structures have been replaced by permanent circuitries. At around 3 months the cortical subplate has dissolved in primary motor and sensory cortices; around 12 months the cortical subplate in prefrontal and parieto-temporal cortices and cerebellar external granular layer have disappeared. This review stresses that families are pivotal in early intervention. It summarizes evidence on the effectiveness of early intervention in medically fragile neonates, infants at low to moderate risk, infants with or at high risk of CP and with or at high risk of ASD.

Temporal and spatial localisation of general movement complexity and variation-Why Gestalt assessment requires experience

Aim

General movements’ assessment (GMA), based on Gestalt perception, identifies infants at risk of cerebral palsy. However, the requirement of ample experience to construct the assessor's inner criteria for abnormal movement hampers its widespread clinical use. This study aims to describe details of general movements (GMs) in various body parts and to investigate their association with GMA‐Gestalt.

Methods

Participants were 24 typically developing infants and 22 very‐high‐risk infants. GMs were assessed during the writhing (0‐8 weeks) and/or fidgety GM phase (2‐5 months) by GMA‐Gestalt and a semi‐quantification of the duration of simple movements and complex movements in various body parts.

Results

During both GM phases, the quality of movement often varied within a single assessment, but the degree of complexity and variation of movements in trunk, arms and legs were interrelated (ρ = 0.32‐0.84). Longer durations of complex movements in arms and legs (P < .042) were further associated with a better quality in GMA‐Gestalt. Head movement was associated with movements in other body parts only in the writhing phase and not associated with GMA‐Gestalt during both GM phases.

Conclusion

Infants did not show consistently over time and across body parts simple or complex movements. Detailed description of movement characteristics may facilitate the development of computer‐based GMA.

The quality of general movements in infants with complex congenital heart disease undergoing surgery in the neonatal period

BACKGROUND

Advances in diagnostic technologies, surgical management, and perioperative care have increased survival for neonates with complex congenital heart disease (CCHD). The success of these advances exposed a heightened risk of brain injury and developmental disabilities. The General Movements Assessment, a non-invasive method, may detect early neurodevelopmental impairments in high-risk infants.

AIMS

To examine whether infants with CCHD undergoing neonatal surgery have higher prevalence of atypical general movements (GMs) than a reference group, and whether single ventricle physiology with systemic oxygen saturations <90% increases risk for atypical GMs.

METHODS

Serial General Movements Assessment (GMA) in a cohort of infants with CCHD (n = 74) at writhing (term-6 weeks) and fidgety (7-17 weeks) GM-age. GMA focused on the presence of definitely abnormal GM-complexity and absent fidgety movements. Single GMAs at 3 months were available from a reference sample of Dutch infants (n = 300). Regression analyses examined relationships between cardiac characteristics and definitely abnormal GM-complexity.

RESULTS

Higher prevalence of definitely abnormal GM-complexity in infants with CCHD compared to reference infants (adjusted OR 5.938, 95% CI 2.423-14.355), single ventricle CCHD increased the risk. Occurrence of absent fidgety movements was similar in infants with CCHD and reference infants (adjusted OR 0.475, 95% CI 0.058-3.876). Systemic postoperative oxygen saturations <90% was associated with higher risk of definitely abnormal GM-complexity at fidgety (adjusted OR 16.445 95% CI 1.149-235.281), not at writhing age.

CONCLUSIONS

Infants with CCHD, especially those with single ventricle CCHD, are at increased risk of definitely abnormal GM-complexity. GMA at fidgety age is recommended.

Atypical general movements in the general population: Prevalence over the last 15 years and associated factors

AIM

To determine the prevalence of atypical general movements (GMs) in the general population, to examine its time trend and associated factors.

METHODS

Participants consisted of 300 infants born in 2016-2018 (current cohort; gestational age 39.4 weeks (27-42); 162 boys), representative of the Dutch population. GMs were assessed at 2-4 months corrected age in terms of GM-complexity (definitely abnormal (DA) or not) and fidgety movements (present or absent). GM-complexity data from a cohort of 455 Dutch infants born in 2001-2002 were used to investigate the time trend.

RESULTS

In the current cohort, 10 infants (3%) showed DA GM-complexity and 8 (3%) absent fidgety movements. Only one infant had both GM-impairments (0.3%). The prevalence of DA GM-complexity did not differ from that in the 2001-2002 cohort (adjusted odds ratio (OR) = 1.47 [0.53, 4.06]). DA GM-complexity was associated with maternal smoking (adjusted OR = 3.59 [1.56, 8.28]) and marginally with prematurity (adjusted OR = 2.78 [1.00, 7.74]); absence of fidgety movements was curvilinearly associated with assessment age only (OR = 1.06 [1.01, 1.12]).

CONCLUSION

In the general population, the prevalence of DA GM-complexity and absent fidgety movements is 3%. The finding that they rarely co-occur and are associated with different factors indicates that GM-assessment needs to address both aspects.

Typical general movements at 2 to 4 months: Movement complexity, fidgety movements, and their associations with risk factors and SINDA scores

BACKGROUND

Movement complexity and the presence of fidgety movements (FMs) during general movements (GMs) both reflect aspects of neurological integrity in early infancy.

AIM

To assess interrelations between the degree of movement complexity and characteristics of FMs during typical GMs and to investigate associations between mildly impaired GMs and risk factors and neurodevelopmental condition.

STUDY DESIGN

Observational cohort study.

SUBJECTS

283 infants (25 born preterm) at 2-4 months corrected age, representative of the general Dutch population.

OUTCOME MEASURES

GMs were classified in terms of GM-complexity (normal or mildly abnormal (MA)) and FMs (clearly present, sporadic, or exaggerated). Concurrent neurological, developmental and socio-emotional status were measured with the Standardized Infant NeuroDevelopmental Assessment (SINDA).

RESULTS

Infants with MA GM-complexity had a higher risk of having sporadic FMs and exaggerated FMs. Perinatal complications were not associated with mildly impaired GMs. MA GM-complexity was associated with advanced maternal age (adjusted OR = 2.29 [1.11, 4.76]) and having a non-native Dutch mother (adjusted OR = 2.93 [1.29, 6.64]). It was also associated with atypical neurological (OR = 7.62 [3.51, 16.54]) and developmental scores (OR = 2.38 [1.16, 4.88]). Sporadic and exaggerated FMs were associated with low-to-middle maternal education (adjusted OR = 2.88, [1.45, 5.72]) and having a non-native Dutch father (adjusted OR = 7.16 [1.41, 36.32]), respectively. However, neither sporadic nor exaggerated FMs were associated with the SINDA outcomes.

CONCLUSIONS

GM-complexity and FMs are two interrelated but different aspects of GMs. Mild impairments in GM-complexity and FMs share a non-optimal socio-economic background as risk factor, but only MA GM-complexity is associated with a concurrent non-optimal neurodevelopmental condition.

The influence of perinatal and maternal factors on physical growth at 12 months in prematurely born infants treated in the neonatal intensive care unit: A retrospective chart review and a prospective cohort study

BACKGROUND

Growth retardation during the first year of life is frequently observed in prematurely born infants. Few reports have considered the effects of maternal emotional distress and perceptions of care burden on the outcomes of these infants.

OBJECTIVES

This study investigated the physical growth trajectories of prematurely born infants treated in neonatal intensive care unit and determined the effects of perinatal factors, maternal emotional distress and perceptions of care burden on growth retardation at 12 months' corrected age.

DESIGN

Retrospective chart review and prospective cohort study.

SETTING

Single neonatal intensive care unit and follow-up outpatient clinics at a maternity and neonatal hospital.

PARTICIPANTS

288 mother-infant pairs in the retrospective chart review and 169 dyads in the prospective cohort study.

METHODS

Medical records of prematurely born infants, perinatal factors and physical growth over a 1-year period were retrospectively reviewed. For the prospective study, mothers completed the Self-Rating Anxiety Scale, Perinatal Post-traumatic Stress Disorder Questionnaire, and Condition Management Effort Scale when infants reached 3 months' corrected age. The generalized linear mixed model was applied to explore effects of maternal emotional disorders and perceptions of care burden on growth retardation at 12 months' corrected age.

RESULTS

The retrospective data showed 13.9%, 10.1%, and 10.1% retardation for head circumference, length, and weight, respectively. Birth weight was negatively associated with physical growth retardation. Delayed breastfeeding initiation, younger mothers, and lower 5-min Apgar score were associated with head circumference retardation. Male sex, higher gestational age, and delayed breastfeeding initiation were risk factors for length retardation; male sex, higher gestational age, and younger mothers for weight. The prospective study showed that head circumference, length, and weight retardation rates were 18.3%, 10.3%, and 16.3%, respectively. Male sex and birth weight, were still significant, while others were not. Moreover, alternative models based on these included factors revealed that maternal perceptions of a higher care burden was a risk factor for overall growth retardation and maternal post-traumatic stress disorder only for a weight problem.

CONCLUSIONS

Physical growth remained a significant problem for prematurely born infants during the first year. This study identified perinatal factors, the level of maternal emotional distress, and perceptions of care burden were related to adverse infant's growth outcomes. Multidisciplinary interventions targeting maternal emotional distress and perceptions of care burden should be developed to promote the growth of prematurely born infants within the first 3 months after birth.

Analyse der Spontanmotorik im 1. Lebensjahr: Markerlose 3-D-Bewegungserfassung zur Früherkennung von Entwicklungsstörungen

Kinder mit motorischer Entwicklungsstörung profitieren von einer frühen Entwicklungsförderung. Eine frühe Diagnosestellung in der kinderärztlichen Vorsorge (U2–U5) kann durch ein automatisiertes Screening verbessert werden. Bisherige Ansätze einer automatisierten Bewegungsanalyse sind jedoch teuer und aufwendig und nicht in der Breite anwendbar. In diesem Beitrag soll ein neues System zur Videoanalyse, das Kinematic Motion Analysis Tool (KineMAT) vorgestellt werden. Es kann bei Säuglingen angewendet werden und kommt ohne Körpermarker aus. Die Methode wird anhand von 7 Patienten mit unterschiedlichen Diagnosen demonstriert.

Mit einer kommerziell erhältlichen Tiefenbildkamera (RGB-D[Red-Green-Blue-Depth]-Kamera) werden 3‑minütige Videosequenzen von sich spontan bewegenden Säuglingen aufgenommen und mit einem virtuellen Säuglingskörpermodell (SMIL[Skinned Multi-infant Linear]-Modell) in Übereinstimmung gebracht. Das so erzeugte virtuelle Abbild erlaubt es, beliebige Messungen in 3‑D mit hoher Präzision durchzuführen. Eine Auswahl möglicher Bewegungsparameter wird mit diagnosespezifischen Bewegungsauffälligkeiten zusammengeführt.

Der KineMAT und das SMIL-Modell erlauben eine zuverlässige, dreidimensionale Messung der Spontanaktivität bei Säuglingen mit einer sehr niedrigen Fehlerrate. Basierend auf maschinellen Lernalgorithmen kann der KineMAT trainiert werden, pathologische Spontanmotorik automatisiert zu erkennen. Er ist kostengünstig und einfach anzuwenden und soll als Screeninginstrument für die kinderärztliche Vorsorge weiterentwickelt werden.

Long-range temporal organisation of limb movement kinematics in human neonates

OBJECTIVE

Movement provides crucial sensorimotor information to the developing brain, evoking somatotopic cortical EEG activity. Indeed, temporal-spatial organisation of these movements, including a diverse repertoire of accelerations and limb combinations (e.g. unilateral progressing to bilateral), predicts positive sensorimotor outcomes. However, in current clinical practice, movements in human neonates are qualitatively characterised only during brief periods (a few minutes) of wakefulness, meaning that the vast majority of sensorimotor experience remains unsampled. Here our objective was to quantitatively characterise the long-range temporal organisation of the full repertoire of newborn movements, over multi-hour recordings.

METHODS

We monitored motor activity across 2-4 h in 11 healthy newborn infants (median 1 day old), who wore limb sensors containing synchronised tri-axial accelerometers and gyroscopes. Movements were identified using acceleration and angular velocity, and their organisation across the recording was characterised using cluster analysis and spectral estimation.

RESULTS

Movement occurrence was periodic, with a 1-hour cycle. Peaks in movement occurrence were associated with higher acceleration, and a higher proportion of movements being bilateral.

CONCLUSIONS

Neonatal movement occurrence is cyclical, with periods consistent with sleep-wake behavioural architecture. Movement kinematics are organised by these fluctuations in movement occurrence. Recordings that exceed 1-hour are necessary to capture the long-range temporal organisation of the full repertoire of newborn limb movements.

SIGNIFICANCE

Future work should investigate the prognostic value of combining these movement recordings with synchronised EEG, in at-risk infants.

The enigmatic fetal subplate compartment forms an early tangential cortical nexus and provides the framework for construction of cortical connectivity

The most prominent transient compartment of the primate fetal cortex is the deep, cell-sparse, synapse-containing subplate compartment (SPC). The developmental role of the SPC and its extraordinary size in humans remain enigmatic. This paper evaluates evidence on the development and connectivity of the SPC and discusses its role in the pathogenesis of neurodevelopmental disorders. A synthesis of data shows that the subplate becomes a prominent compartment by its expansion from the deep cortical plate (CP), appearing well-delineated on MR scans and forming a tangential nexus across the hemisphere, consisting of an extracellular matrix, randomly distributed postmigratory neurons, multiple branches of thalamic and long corticocortical axons. The SPC generates early spontaneous non-synaptic and synaptic activity and mediates cortical response upon thalamic stimulation. The subplate nexus provides large-scale interareal connectivity possibly underlying fMR resting-state activity, before corticocortical pathways are established. In late fetal phase, when synapses appear within the CP, transient the SPC coexists with permanent circuitry. The histogenetic role of the SPC is to provide interactive milieu and capacity for guidance, sorting, "waiting" and target selection of thalamocortical and corticocortical pathways. The new evolutionary role of the SPC and its remnant white matter neurons is linked to the increasing number of associative pathways in the human neocortex. These roles attributed to the SPC are regulated using a spatiotemporal gene expression during critical periods, when pathogenic factors may disturb vulnerable circuitry of the SPC, causing neurodevelopmental cognitive circuitry disorders.