Embodiment in early development

Using deep learning to classify developmental differences in reaching and placing movements in children with and without autism spectrum disorder

Autism Spectrum Disorder (ASD) is among the most prevalent neurodevelopmental disorders, yet the current diagnostic procedures rely on behavioral analyses and interviews, without objective screening methods to support the diagnostic process. This study seeks to address this gap by integrating upper limb kinematics and deep learning methods to identify potential biomarkers that could be validated in younger age groups in the future to enhance the identification of ASD. Forty-one school-age children, with and without an ASD diagnosis (mean age ± SE: TD group: 10.3 ± 0.8, 8 males and 7 females; ASD group: 10.3 ± 0.5, 21 males and 5 females), participated in the study. A single Inertial Measurement Unit (IMU) was affixed to the child's wrist as they engaged in a continuous reaching and placing task. Deep learning techniques were employed to classify children with and without ASD. Our findings suggest differential movement kinematics in school-age children compared to healthy adults. Compared to TD children, children with ASD exhibited poor feedforward/feedback control of arm movements as seen by greater number of movement units, more movement overshooting, and prolonged time to peak velocity/acceleration. Unique movement strategies such as greater velocity and acceleration were also seen in the ASD group. More importantly, using Multilayer Perceptron (MLP) model, we demonstrated an accuracy of ~ 78.1% in classifying children with and without ASD. These findings underscore the potential use of studying upper limb movement kinematics during goal-directed arm movements and deep learning methods as valuable tools for classifying and, consequently, aiding in the diagnosis and early identification of ASD upon further validation of their specificity among younger children.

The role of action concepts in physical reasoning: insights from late childhood

A fundamental component of human cognition is the ability to intuitively reason about behaviours of objects and systems in the physical world without resorting to explicit scientific knowledge. This skill was traditionally considered a symbolic process. However, in the last decades, there has been a shift towards ideas of embodiment, suggesting that accessing physical knowledge and predicting physical outcomes is grounded in bodily interactions with the environment. Infants and children, who learn mainly through their embodied experiences, serve as a model to probe the link between reasoning and physical concepts. Here, we tested school-aged children (5- to 15-year-olds) in online reasoning games that involve different physical action concepts such as supporting, launching and clearing. We assessed changes in children's performance and strategies over development and their relationships with the different action concepts. Children reasoned more accurately in problems that involved supporting actions compared to launching or clearing actions. Moreover, when children failed, they were more strategic in subsequent attempts when problems involved support rather than launching or clearing. Children improved with age, but improvements differed across action concepts. Our findings suggest that accessing physical knowledge and predicting physical events are affected by action concepts, and those effects change over development. This article is part of the theme issue 'Minds in movement: embodied cognition in the age of artificial intelligence'.

Echoes of a living body: A mind-body approach on how women victims of intimate partner violence experience their bodies

Intimate partner violence (IPV) against women is a worldwide health problem. IPV impact on women's embodiment remains embedded in their narratives. However, the subjective complexity of victims' embodiment and its impact on healthcare still urges to be understood. We aimed to understand (i) how women victims of IPV experience their bodies and (ii) the impact of IPV in their embodiment. From a thematic analysis of six interviews with women victims, four themes arouse: Living body, Reaction to adversities, Impact of violence and Identity. Participants revealed a tendency to perceive negative bodily sensations, the body as restrictive of their ability to react to illnesses and other adversities, and impacts on health and decision-making processes. We encourage healthcare providers to be responsive to the feelings of physical and psychological exhaustion experienced by victims and highlight the potential of promoting positive bodily experiences in the support given to women.

Developmental associations between motor and communication outcomes in Fragile X syndrome: Variation in the context of co-occurring autism

LAY ABSTRACT

Fragile X syndrome (FXS), the leading heritable cause of intellectual disability, has a co-occurrence rate of autism spectrum disorder (ASD) estimated at ~60%. Children with FXS experience delayed achievement and slower development of key motor abilities, which happens to an even greater extent for children with both FXS and ASD. A multitude of studies have demonstrated that motor abilities are foundational skills related to later communication outcomes in neurotypical development, as well as in the context of ASD. However, these associations remain unexamined in FXS, or FXS + ASD. In this study, we aimed to determine the associations between early motor skills and their rate of development on communication outcomes in FXS. Furthermore, we investigated whether these associations varied in the context of co-occurring FXS + ASD. Results revealed within-FXS variation in the context of co-occurring ASD between some aspects of motor development and communication outcomes, yet within-FXS consistency between others. Findings provide evidence for variability in developmental processes and outcomes in FXS in the context of co-occurring ASD and offer implications for intervention.

The implementation of EMI-Heart, a family-tailored early motor intervention in infants with complex congenital heart disease, in practice: a feasibility RCT

BACKGROUND

Children with congenital heart disease (CHD) who undergo open-heart surgery are at risk of developmental impairment, including motor delay, which contributes to parental concerns. Additionally, parents experience prolonged stress associated with their child's disease. There is a lack of early motor interventions in infants with CHD accounting for parental burdens. We developed a family-tailored early motor intervention (EMI-Heart), aiming to promote motor development in infants with CHD and family well-being. The primary aim was to evaluate the feasibility of the study design and the intervention. The secondary aim was to evaluate differences between the intervention and the control group in motor outcomes and family well-being at baseline (3-5 months), post-treatment (6-8 months), and at follow-up (12 months).

METHOD

In this single-centre feasibility randomized control trial (RCT), infants with CHD after open-heart surgery without genetic or major neurological comorbidities were randomly allocated to EMI-Heart or the control group (standard of care). EMI-Heart's key elements promote postural functional activities and encourage parental sensitivity to infants' motor and behaviour cues. Infants assigned to EMI-Heart received nine sessions of early motor intervention at home, in the hospital, and online for a duration of 3 months by a paediatric physiotherapist. We performed descriptive statistics for feasibility and secondary outcomes.

RESULTS

The recruitment rate was 59% (10/17), all participating families completed the study (10/10), and the intervention duration was 3.9 months (± 0.54), including nine intervention sessions per family. Median acceptability to parents was 3.9 (1 = not agree-4 = totally agree, Likert scale). The paediatric physiotherapist considered the intervention as feasible. The comparison of motor outcomes did not show differences between groups. However, we detected improved reliable change scores in family well-being outcomes for families of the intervention group compared to the controls.

CONCLUSIONS

Our research indicates that EMI-Heart is a feasible intervention for infants with CHD after open-heart surgery. The intervention was highly acceptable both to parents and to the paediatric physiotherapist. Online treatment sessions offer a valuable alternative to home and hospital visits. This feasibility RCT provides a foundation for a future full trial.

TRIAL REGISTRATION

ClinicalTrials.gov, NCTT04666857. Registered 23.11.2020.

Developmental Differences in Reaching-and-Placing Movement and Its Potential in Classifying Children with and without Autism Spectrum Disorder: Deep Learning Approach

Autism Spectrum Disorder (ASD) is among the most prevalent neurodevelopmental disorders, yet the current diagnostic procedures rely on behavioral analyses and interviews and lack objective screening methods. This study seeks to address this gap by integrating upper limb kinematics and deep learning methods to identify potential biomarkers that could be validated in younger age groups in the future to enhance the identification of ASD. Forty-one school-age children, with and without an ASD diagnosis (Mean age ± SE = 10.3 ± 0.4; 12 Females), participated in the study. A single Inertial Measurement Unit (IMU) was affixed to the child's wrist as they engaged in a continuous reaching and placing task. Deep learning techniques were employed to classify children with and without ASD. Our findings suggest delays in motor planning and control in school-age children compared to healthy adults. Compared to TD children, children with ASD exhibited poor motor planning and control as seen by greater number of movement units, more movement overshooting, and prolonged time to peak velocity/acceleration. Compensatory movement strategies such as greater velocity and acceleration were also seen in the ASD group. More importantly, using Multilayer Perceptron (MLP) model, we demonstrated an accuracy of ~ 78.1% in classifying children with and without ASD. These findings underscore the potential use of studying upper limb movement kinematics during goal-directed arm movements and deep learning methods as valuable tools for classifying and, consequently, aiding in the diagnosis and early identification of ASD upon further validation in younger children.

Improving access to assessments of early motor development in local languages: polish adaptation of the Early Motor Questionnaire

A child's motor development progresses very dynamically. It is crucial to develop freely available parent-report measures of motor development that can be easily used globally to measure motor skills and identify children in need of interventions. This paper presents the adaptation and validation of the Early Motor Questionnaire, which consists of gross motor (GM), fine motor (FM), and perception-action integration (PA) subscales, to the Polish language (EMQ-PL). Study 1 (online, cross-sectional, N = 640) assessed psychometric properties of the EMQ-PL and its value in identifying children referred to physiotherapy. Results reveal excellent psychometric properties of the EMQ-PL and differences in GM and total age-independent scores between children that were and were not referred for physiotherapy. Study 2 (in-person assessment, longitudinal, N = 100) showed high correlations of GM and total scores with Alberta Infant Motor Scale.

CONCLUSION

Overall, the EMQ can be easily adapted to local languages and has the potential for use as a screening tool in global health contexts.

WHAT IS KNOWN

• Parent-report questionnaires - especially those available free of charge - can potentially improve the rapid assessment of motor skills in young children worldwide. • Translation, adaptation and validation of freely available parent-report measures of motor development to local languages are important for local populations.

WHAT IS NEW

• Early Motor Questionnaire can be easily adapted to local languages and has the potential for use as a screening tool in global health contexts. • The polish version of the Early Motor Questionnaire has excellent psychometric properties and highly correlates with infants' age and Alberta Infant Motor Scale scores.

A family-tailored early motor intervention (EMI-Heart) for infants with complex congenital heart disease: study protocol for a feasibility RCT

BACKGROUND

Children with congenital heart disease (CHD) undergoing open-heart surgery are at risk for developmental impairments with motor delay manifesting first and contributing to parental concerns. Only a few interventional studies aim to improve neuromotor development in infants with CHD with inconclusive results. We thus developed a family-tailored early motor intervention (EMI-Heart), which aims to promote motor development and family well-being in the first year of life after open-heart surgery. The primary aim described in this protocol is to evaluate feasibility of EMI-Heart. The secondary aim is to describe the difference between the intervention and control group in motor outcomes and family well-being at baseline, post-treatment, and follow-up.

METHODS

This prospective, parallel single-center feasibility randomized controlled trial (RCT) will compare EMI-Heart with standard of care in infants with complex CHD. Sixteen infants and their families, randomly allocated to EMI-Heart or the control group, will participate within the first 5 months of life. Infants assigned to EMI-Heart will receive early motor intervention for 3 months. The intervention's key is to promote infants' postural control to enhance motor development and partnering with parents to encourage family well-being. Feasibility outcomes will be (a) clinical recruitment rate and percentage of families completing EMI-Heart, (b) average duration and number of sessions, and (c) acceptability of EMI-Heart using a parental questionnaire post-treatment, and descriptive acceptability of EMI-Heart to the pediatric physiotherapist. Secondary outcomes of the intervention and control group will be infants' motor outcomes and questionnaires assessing family well-being at 3-5 months (baseline), at 6-8 months (post-treatment), and at 12 months of age (follow-up). We will evaluate feasibility using descriptive statistics. Non-parametric statistical analysis of secondary outcomes will assess differences between the groups at baseline, post-treatment, and follow-up.

DISCUSSION

This feasibility RCT will provide information about a newly developed family-tailored early motor intervention in infants with complex CHD. The RCT design will provide a foundation for a future large-scale interventional trial for infants with CHD after open-heart surgery.

TRIAL REGISTRATION

This study protocol (version 1.3, 01.02.2022) was approved by the Cantonal Ethics Commission Zurich (BASEC-Nr. 2019-01,787) and is registered by Clinicaltrials.gov (NCTT04666857).

Infants’ Prediction of Humanoid Robot’s Goal-Directed Action

Several studies have shown that infants anticipate human goal-directed actions, but not robot’s ones. However, the studies focusing on the robot goal-directed actions have mainly analyzed the effect of mechanical arms on infant’s attention. To date, the prediction of goal-directed actions in infants has not yet been studied when the agent is a humanoid robot. Given this lack of evidence in infancy research, the present study aims at analyzing infants’ action anticipation of both a human’s and a humanoid robot’s goal-directed action. Data were acquired on thirty 17-month-old infants, watching four video clips, where either a human or a humanoid robot performed a goal-directed action, i.e. reaching a target. Infants looking behavior was measured through the eye-tracking technique. The results showed that infants anticipated the goal-directed action of both the human and the robot and there were no differences in the anticipatory gaze behavior between the two agents. Furthermore, the findings indicated different attentional patterns for the human and the robot, showing a greater attention paid to the robot's face than the human’s face. Overall, the results suggest that 17-month-old infants may infer also humanoid robot’ underlying action goals.

Motor Influences on Communication: Comparisons Between Down Syndrome and Fragile X Syndrome

Motor skills, an important foundation for language and communication, are considerably delayed in children with Down syndrome (DS) and fragile X syndrome (FXS). However, the impact of these impairments on expressive and receptive communication and the phenotypic specificity of these associations remains unknown. Participants included 37 with DS and 37 age and developmentally matched children with FXS. Syndrome-specific motor and communication profiles emerged, with higher communication scores seen in the DS versus FXS on, but lower gross motor scores. Significant associations between domains of motor and communication were identified for both groups with additional phenotype-specific patterns. Findings demonstrate the importance of early motor abilities for communication in DS and FXS. Implications for phenotypic specificity and targeted intervention are discussed.

A Developmental Framework for Embodiment Research: The Next Step Toward Integrating Concepts and Methods

Embodiment research is at a turning point. There is an increasing amount of data and studies investigating embodiment phenomena and their role in mental processing and functions from across a wide range of disciplines and theoretical schools within the life sciences. However, the integration of behavioral data with data from different biological levels is challenging for the involved research fields such as movement psychology, social and developmental neuroscience, computational psychosomatics, social and behavioral epigenetics, human-centered robotics, and many more. This highlights the need for an interdisciplinary framework of embodiment research. In addition, there is a growing need for a cross-disciplinary consensus on level-specific criteria of embodiment. We propose that a developmental perspective on embodiment is able to provide a framework for overcoming such pressing issues, providing analytical tools to link timescales and levels of embodiment specific to the function under study, uncovering the underlying developmental processes, clarifying level-specific embodiment criteria, and providing a matrix and platform to bridge disciplinary boundaries among the involved research fields.

Communication changes when infants begin to walk

Learning to walk allows infants to travel faster and farther and explore more of their environments. In turn, walking may have a cascading effect on infants' communication and subsequent responses from caregivers. We tested for an inflection point-a dramatic shift in the developmental progression-in infant communication and caregiver responses when infants started walking. We followed 25 infants longitudinally over 7 months surrounding the onset of walking (mean walk onset age = 11.76 months, SD = 1.56). After learning to walk, the pace of gesture growth (but not vocalization growth) increased substantially, and infants increasingly coordinated gestures and vocalizations with locomotion (e.g., by walking to a caregiver and showing off a toy bear). Consequently, caregivers had more opportunities to respond contingently to their infants during walking months compared to crawling months (e.g., "What did you find? Is that your bear?"). Changes in communication were amplified for infants who began walking at older ages, compared to younger walkers. Findings suggest that learning to walk marks a point in development when infants actively communicate in new ways, and consequently elicit rich verbal input from caregivers.

Quantitative analysis of spontaneous sociality in children's group behavior during nursery activity

Sociality is the tendency to spontaneously interact with others to establish and maintain relationships. Some approaches, including questionnaires, tests, controlled experiments, and qualitative field research, cannot capture complex social interactions, such as in children during nursery activities, because of problems with ecological validity and the labor cost of analysis. Here, we introduced a new methodology for the quantitative analysis of spontaneous social movement and investigated children's group behavior using position data. We periodically visited a nursery and recorded videos of eurhythmics, in which children move in tune with music, in different classes. The results revealed that children in the six-year-old class approached others in a short period of time (within one second) and established group behavior like that in a game of tag. It can be interpreted that such social behavior may include actions related to the cognition of anticipating others' behaviors in a complex situation. Although only a small amount of data could be acquired, this study suggests one of the characteristics of social behaviors in the classroom considering an ecological approach.

START-Play Physical Therapy Intervention Impacts Motor and Cognitive Outcomes in Infants With Neuromotor Disorders: A Multisite Randomized Clinical Trial

OBJECTIVE

Our objective was to evaluate the efficacy of the Sitting Together and Reaching to Play (START-Play) intervention in young infants with neuromotor disorders.

METHOD

This randomized controlled trial compared usual care early intervention (UC-EI) with START-Play plus UC-EI. Analyses included 112 infants with motor delay (55 UC-EI, 57 START-Play) recruited at 7 to 16 months of age across 5 sites. START-Play included twice-weekly home visits with the infant and caregiver for 12 weeks provided by physical therapists trained in the START-Play intervention; UC-EI was not disrupted. Outcome measures were the Bayley Scales of Infant and Toddler Development, Third Edition (Bayley); the Gross Motor Function Measure; reaching frequency; and the Assessment of Problem Solving in Play (APSP). Comparisons for the full group as well as separate comparisons for infants with mild motor delay and infants with significant motor delay were conducted. Piecewise linear mixed modeling estimated short- and long-term effects.

RESULTS

For infants with significant motor delay, positive effects of START-Play were observed at 3 months for Bayley cognition, Bayley fine motor, and APSP and at 12 months for Bayley fine motor and reaching frequency outcomes. For infants with mild motor delay, positive effects of START-Play for the Bayley receptive communication outcome were found. For the UC-EI group, the only difference between groups was a positive effect for the APSP outcome, observed at 3 months.

CONCLUSION

START-Play may advance reaching, problem solving, cognitive, and fine motor skills for young infants with significant motor delay over UC-EI in the short term. START-Play in addition to UC-EI may not improve motor/cognitive outcomes for infants with milder motor delays over and above usual care.

IMPACT

Concepts of embodied cognition, applied to early intervention in the START-Play intervention, may serve to advance cognition and motor skills in young infants with significant motor delays over usual care early intervention.

LAY SUMMARY

If you have a young infant with significant delays in motor skills, your physical therapist can work with you to develop play opportunities to enhance your child's problem solving, such as that used in the START-Play intervention, in addition to usual care to help your child advance cognitive and motor skills.

Reflections on Motor Development Research Across the 20th Century: Six Empirical Studies That Changed the Field

Motor development research has had a rich history over the 20th century with a wide array of scientists contributing to a broad and deep body of literature. Just like the process of development, progress within the field has been non-linear, with rapid periods of growth occurring after the publication of key research articles that changed how we conceptualized and explored motor development. These publications provided new ways to consider developmental issues and, as a result, ignited change in our theoretical and empirical approaches within the field of motor development and the broader field of developmental psychology. In this paper, we outline and discuss six pioneering studies that we consider significant in their impact and in the field’s evolution, in order of publication: Halverson, 1931; Wild, 1938; Gibson & Walk, 1960; Connolly, Brown, & Bassett, 1968; Thelen & Fisher, 1982; Thelen & Ulrich, 1991. We have limited this review to empirical papers only. Together, they offer insight into what motor development research is, where it came from, why it matters, and what it has achieved.

What Does Dorsal Cortex Contribute to Perception?

According to the influential "Two Visual Pathways" hypothesis, the cortical visual system is segregated into two pathways, with the ventral, occipitotemporal pathway subserving object perception, and the dorsal, occipitoparietal pathway subserving the visuomotor control of action. However, growing evidence suggests that the dorsal pathway also plays a functional role in object perception. In the current article, we present evidence that the dorsal pathway contributes uniquely to the perception of a range of visuospatial attributes that are not redundant with representations in ventral cortex. We describe how dorsal cortex is recruited automatically during perception, even when no explicit visuomotor response is required. Importantly, we propose that dorsal cortex may selectively process visual attributes that can inform the perception of potential actions on objects and environments, and we consider plausible developmental and cognitive mechanisms that might give rise to these representations. As such, we consider whether naturalistic stimuli, such as real-world solid objects, might engage dorsal cortex more so than simplified or artificial stimuli such as images that do not afford action, and how the use of suboptimal stimuli might limit our understanding of the functional contribution of dorsal cortex to visual perception.

Investigating the Effects of Embodiment on Emotional Categorization of Faces and Words in Children and Adults

The facial feedback hypothesis (FFH) indicates that besides being involved in the production of facial expressions, the musculature of the face also influences one's perception of emotional stimuli. Recently, this effect has been the focus of increased scrutiny as efforts to replicate a key study with adult participants supporting this hypothesis, using the so-called "pen-in-the-mouth" task, have not been successful at several labs. Our series of experiments attempted to investigate whether the assumed embodiment effect can be reproduced in a simplified emotional categorization task for emotional faces and words. We also wanted to test whether the embodiment effect can be detected in children because it is assumed that their bodily processes are especially closely linked with their sensory and cognitive processes. Our experiments involved child and adult participants categorizing faces and words as positive or negative as quickly as possible, while inducing a positive or negative facial or bodily state (holding a straw in the mouth such that a smile or a frown was generated, or creating a positive or negative body posture). The positive or negative facial and bodily states could therefore be either congruent or incongruent with the valence of the target face and word stimuli. Our results did not show any significant differences between the congruent and incongruent conditions in either children or adults. This suggests that embodiment effects either do not significantly impact valence-based categorization or are not strong enough to be detected by our approach considering the sample size in the present study.

To have and to hold: embodied ownership is established in early childhood

We investigated whether embodied ownership is evident in early childhood. To do so, we gifted a drinking bottle to children (aged 24-48 months) to use for 2 weeks. They returned to perform reach-grasp-lift-replace actions with their own or the experimenter's bottle while we recorded their movements using motion capture. There were differences in motor interactions with self- vs experimenter-owned bottles, such that children positioned self-owned bottles significantly closer to themselves compared with the experimenter's bottle. Age did not modulate the positioning of the self-owned bottle relative to the experimenter-owned bottle. In contrast, the pattern was not evident in children who selected one of the two bottles to keep only after the task was completed, and thus did not 'own' it during the task (Experiment 2). These results extend similar findings in adults, confirming the importance of ownership in determining self-other differences and provide novel evidence that object ownership influences sensorimotor processes from as early as 2 years of age.

Systematic Review of the Main Motor Scales for Clinical Assessment of Individuals with down Syndrome

Objective: The aim of the present review was to identify the motor scales currently used to assess individuals with Down Syndrome (DS).Method: PubMed, WOS and BVS databases were systematically searched to identify the most relevant published studies that used motor scales in the evaluation of individuals with DS.Results: Of the 99 studies that met the eligibility criteria in this process, 20 experimental and observational studies were found to fully meet the eligibility criteria.Conclusion: We identified several motor scales including the Alberta Infant Motor Scale (AIMS), Test of Infant Motor Performance (TIMP), BAYLEY, Peabody Gross Motor Scale (PGMS-PDMS-GM), Gross Motor Function Measure (GMFM), Movement Assessment Battery for Children (MABC) and Pediatric Evaluation of Disability Inventory (PEDI).

Twelve-Month-Old Infants Respond to Speech About Absent Inaccessible Objects

This article investigated the interplay of 12-month-old infants' perception of affordances for locomotion and their ability to respond to the mention of hidden objects. In Experiment I, a toy was hidden in an ottoman that was placed on a cabinet out of infants' reach. Infants were more likely to look at, point to or approach the ottoman when there were stairs leading to it than when there were none. The stairs did not help infants respond by highlighting the target corner of the room (Experiment II) or by boosting their engagement with the study events (Experiment III). This suggests that infants' perception of the accessibility of the hiding location influences their ability to respond to speech about absent things.

Developmental divergence: motor trajectories in children with fragile X syndrome with and without co-occurring autism

BACKGROUND

Autism spectrum disorder (ASD) is highly prevalent in fragile X syndrome (FXS), affecting 50-70% of males. Motor impairments are a shared feature across autism and FXS that may help to better characterize autism in FXS. As motor skills provide a critical foundation for various language, cognitive, and social outcomes, they may serve an important mechanistic role for autism in FXS. As such, this study aimed to identify differences in motor trajectories across direct assessment and parent-report measures of fine and gross motor development between FXS with and without autism, and typical development, while controlling for cognitive functioning.

METHODS

This prospective longitudinal study included 42 children with FXS, 24 of whom also had ASD (FXS + ASD), as well as 40 typically developing children. The Mullen Scales of Early Learning provided a direct measure of fine and gross motor skills, and the Vineland Adaptive Behavior Scales provided a measure of parent-reported fine and gross motor skills. Random slopes and random intercepts multilevel models were tested to determine divergence in developmental motor trajectories between groups when controlling for cognitive level.

RESULTS

Model results indicated the children with FXS + ASD diverged from TD children by 9-months on all measures of gross and fine motor skills, even when controlling for cognitive level. Results also indicated an early divergence in motor trajectories of fine and gross motor skills between the FXS + ASD and FXS groups when controlling for cognitive level. This divergence was statistically significant by 18 months, with the FXS + ASD showing decelerated growth in motor skills across direct observation and parent-report measures.

CONCLUSIONS

This study is the first to examine longitudinal trends in motor development in children with FXS with and without comorbid ASD using both direct assessment and parent-report measures of fine and gross motor. Furthermore, it is among the first to account for nonverbal cognitive delays, a step towards elucidating the isolated role of motor impairments in FXS with and without ASD. Findings underscore the role of motor impairments as a possible signal representing greater underlying genetic liability, or as a potential catalyst or consequence, of co-occurring autism in FXS.

Embodied Cognition in Practice: Exploring Effects of a Motor-Based Problem-Solving Intervention

BACKGROUND

Embodied cognition interests physical therapists because efforts to advance motor skills in young infants can affect learning. However, we do not know if simply advancing motor skill is enough to support advances in cognition.

OBJECTIVE

The objective was to examine the effect of 2 interventions on the developing motor skill of sitting and problem solving and to describe the feasibility of using eye-tracking technology to explore visual and motor interaction.

DESIGN

This was a longitudinal, randomized comparison of interventions.

METHODS

Twenty infants with developmental delay and/or cerebral palsy, ranging in age from 8 to 34 months (mean [SD] = 15 [6.9] months), participated in an intervention emphasizing motor-based problem solving, and an intervention focused on advancing motor skill through assistance for attaining optimal movement patterns. Outcome measures were the Gross Motor Function Measure sitting subsection and the Early Problem Solving for Infants test. Active touch and looks were measured with eye-tracking technology.

RESULTS

Participants in both groups made significant motor gains from baseline, with no difference between intervention groups on Gross Motor Function Measure change scores. Participants in the problem-solving group showed significant gains in Early Problem Solving for Infants scores over the participants in the optimal movement patterns group. Overall, participants increased active touch of toys and increased concurrent looking with active touching.

LIMITATIONS

This exploratory study was small, with variation in participants' skills. The sampled behaviors for analysis were a small portion of the overall function of the participant.

CONCLUSIONS

An intervention using motor-based problem solving could improve infants' problem-solving skill. The use of eye-tracking could help to understand embodied cognition as infants develop, but the challenges of embedding the method in natural settings require further work. Listen to the author interview at https://academic.oup.com/ptj/pages/podcasts.

Development Through the Lens of a Perception-Action-Cognition Connection: Recognizing the Need for a Paradigm Shift in Clinical Reasoning

Clinical assessment of movement and posture guides the decision-making process in designing interventions for infants and children with movement disorders. Clinical reasoning is influenced by the therapist's understanding of developmental processes. The views of development grounded in perception-action, dynamic systems, and neuronal group selection theories are well recognized in current literature and supported by a large body of research. Based on the available evidence, intervention must be task-specific, repetitive, and highly salient to the child. Furthermore, it must honor spontaneous exploration and active problem-solving, enhance the child's ability to perceive environmental affordances, and target optimal variability and adaptability of movement and posture. However, a neuromaturational approach to developmental assessment and intervention that relies on "teaching" motor milestones and emphasizes the importance of correcting movement patterns in infants and children developing atypically is still prevalent in the clinic. This perspective paper will: (1) examine evidence in support of a paradigm shift from neuromaturational views toward bringing the concepts of grounded cognition, variability, complexity, and adaptability to the forefront of clinical reasoning; and (2) introduce the Perception-Action Approach as a method of assessment and intervention that may serve as an agent of such a shift by augmenting knowledge translation for the clinician.

The Relation Between Walking and Language in Infant Siblings of Children With Autism Spectrum Disorder

In typical development, walk onset is accompanied by increased language growth (e.g., Walle & Campos, 2014). The present study explored whether this relation may be disrupted in the infant siblings of children with autism spectrum disorder (ASD; heightened risk of receiving an ASD diagnosis; HR), a population exhibiting substantial variability in motor and language development (e.g., Gamliel, Yirmiya, & Sigman, 2007; Landa & Garrett-Mayer, 2006). Receptive and expressive language were examined across the transition to walking in three groups of HR infants (no diagnosis, language delay, and ASD; N = 91, 8-18 months) and in infants with no family history of ASD (N = 25; 9-15 months). Only infants with an eventual ASD diagnosis did not show increased language growth following walk onset.

Meilensteine der Motorischen Verhaltensforschung

Zusammenfassung. Die Forschung zum motorischen Verhalten hat eine lange Tradition, wobei eine Vielzahl von Forschern zu einem breiten und tiefgehenden Verständnis des Themas beigetragen haben. Der Erkenntnisgewinn und Fortschritt in der Theorieentwicklung innerhalb des Feldes war zudem meist nicht-linear, sondern gezeichnet durch schnelle Wachstumsphasen nach der Veröffentlichung wichtiger Forschungsartikel und neuer theoretischer Perspektiven. Diese veränderten die Art und Weise wie wir das motorische Verhalten heute konzipieren; und sie sind noch nicht abgeschlossen. Wir werden einige der innovativsten und wirkungsvollsten Theorien und Entwicklungen auf dem Gebiet des motorischen Verhaltens (untergliedert in die drei Hauptbereiche Entwicklung, Kontrolle und Lernen) des letzten Jahrhunderts skizzieren und diskutieren. Darüber hinaus werden wir frühe, wegweisende Forschungsarbeiten vorstellen, die wir für unverzichtbar für das Studium der Motorikforschung halten. Der Blick zurück soll uns erlauben, eine Richtung für die Zukunft zu zeichnen und zu diskutieren. Diese Forschungsthemen können und werden (hoffentlich) in den nächsten Jahrzehnten in vielen Bereichen der Gesellschaft, einschließlich des Sports und der Bewegungswissenschaft, der Robotikforschung und der Klinik, einen wichtigen Einfluss auf die Entwicklung einer gesunden Lebenswelt haben.

Infant Motor Development in Autism Spectrum Disorder: A Synthesis and Meta-analysis

Studies of infant motor development in autism spectrum disorder (ASD) have increased in recent years. This article synthesized this literature through meta-analysis to assess (a) whether infant motor ability differs in ASD relative to neurotypical controls; and (b) whether motor ability and communication are related in infants with ASD. Study 1 aggregated data from 1,953 infants with ASD (ages 3.0-42.0 months), and Study 2 included 890 infants with ASD (age 6.0-42.9 months). Study 1 revealed that infant motor ability differed significantly in ASD compared with neurotypical infants-this difference was robust to variation in measurement and design. Furthermore, this group difference amplified as age increased. Study 2 indicated that within ASD, infant motor ability and communication are related.

Adaptive behavior in infants and toddlers with Down syndrome and fragile X syndrome

Individuals with Down syndrome (DS) experience deficits across all domains of adaptive functioning, however little is known about the emergence and age-related changes of these impairments compared to other neurogenetic disorders with similar intellectual disability impairments, such as fragile X syndrome (FXS). Adaptive behavior is key for optimal functioning in these populations. Participants aged 5-45 months comprised three age-matched groups, DS (n = 64), FXS (n = 69), and typically developing controls (TD; n = 69). Adaptive behavior was measured on the Vineland Adaptive Behavior Scales-II. Regressions were used to examine adaptive behavior in a cross-sectional design across age. DS infants and toddlers evidenced deficits across all areas of adaptive behaviors compared to the age-matched TD group, with clear impairments present in the first year of life. Motor skills were the area of greatest weakness in children with DS with significant impairment evident at 12 months of age that remained low through 3 years. Compared to age-matched children with FXS, children with DS showed initially lower standard scores at 12 months of age, but slower declines in standard scores across age, resulting in less impaired functioning at 36 months. This is the first study to compare adaptive behavior in infants and toddlers with DS to FXS, and demonstrate the phenotypic specificity of adaptive profiles in this diagnostic group. These findings provide evidence that adaptive behavior should be a major target of intervention in children with FXS and DS, and that these differences are potentially driven by unique etiologies attributable to each disorder.