Reaching strategies of very preterm infants at 8 months corrected age

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

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

Late preterm and very preterm infants differ in the acquisition time and quantity of reaches with grasping at reaching onset: an exploratory study

Introduction

The onset of manual reaching allows the expansion of the infant's interaction with the environment. When born preterm, infants become vulnerable to problems in the development of reaching. However, it is still unknown whether there are differences in reaching according to the degree of prematurity.

Objective

This study aimed to explore the differences in reaching acquisition and behavior between late preterm and very preterm infants, as well as whether age and clinical variables influence the results.

Method

This is an exploratory, comparative, observational study. In total, 24 infants were included soon after reaching onset; 12 infants were born late preterm (35.55 ± 0.67 gestational weeks) and 12 very preterm (30.60 ± 0.05 gestational weeks). Infants were placed in a baby seat, and a toy was placed at a reachable distance for 2 min. Reaching behavior was the primary variable; birth weight and length of hospital stay were secondary variables.

Results

The age of reaching onset was higher in the very preterm group. The proportion of reaches with grasping was higher in the late preterm group. These differences were affected by the lower birth weight and longer length of hospital stay in the very preterm group. The proportions of proximal and distal adjustments did not differ between groups.

Conclusion

Very preterm infants presented disadvantages in the acquisition time and the number of reaches with grasping, but not in the proportions of proximal and distal adjustments of reaching, relative to late preterm infants. Group differences were influenced by clinical variables.

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

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

Early exploration of one's own body, exploration of objects, and motor, language, and cognitive development relate dynamically across the first two years of life

Early exploratory behaviors have been proposed to facilitate children's learning, impacting motor, cognitive, language, and social development. This study related the performance of behaviors used to explore oneself to behaviors used to explore objects, and then related both types of exploratory behaviors to motor, language, and cognitive measures longitudinally from 3 through 24 months of age via secondary analysis of an existing dataset. Participants were 52 children (23 full-term, 29 preterm). Previously published results from this dataset documented delays for preterm relative to full-term infants in each assessment. The current results related performance among the assessments throughout the first 2 years of life. They showed that the developmental trajectories of behaviors children used for self-exploration closely related to the trajectories of behaviors they employed to explore objects. The trajectories of both self and object exploration behaviors significantly related to trajectories of children's motor, language, and cognitive development. Specifically, significant relations to global development were observed for self-exploratory head lifting, midline head and hand positioning, hand opening, and behavioral variability, as well as for object-oriented bimanual holding, mouthing, looking, banging, manipulating, transferring of objects, and behavioral intensity and variability. These results demonstrate continuity among the early exploratory behaviors infants perform with their bodies alone, exploratory behaviors with portable objects, and global development. The findings identify specific self- and object-exploration behaviors that may serve as early indicators of developmental delay and could be targeted by interventions to advance motor, language, and cognitive outcomes for infants at risk for delay. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Infant Reaching in the First Year of Life: A Scoping Review of Typical Development and Examples of Atypical Development

AIMS

Our objective was to identify the most common variables used for infant reaching assessment, describe values of these variables across the first year of life, and identify methodological considerations and knowledge gaps for future research.

METHODS

Studies were included if they met the following criteria: (1) assessed infant reaching in any position, (2) included a sample of infants with typical development: healthy, full-term, with no known impairments, (3) infants were under one year old at the first data collection, and (4) counted successful reaches resulting in object contact.

RESULTS

We identified 6 commonly assessed kinematic reaching variables: frequency, duration, movement units, peak velocity, average velocity, and straightness index. Methodological inconsistencies limit our ability to interpret values of these variables across studies.

CONCLUSIONS

Eliminating inconsistencies in study design and data analysis methods is the next step to defining a normative reference standard for reaching development. Establishing a normative reference standard for reaching in the first year of life will be important for assessment of typical and atypical reaching development.

Reaching skills in six-month-old infants at environmental and biological risk

OBJECTIVES

To assess kinematic parameters and proximal and distal reaching adjustments of infants at biological or environmental risk and compare with reaching performance of six-month-old full-term infants without known risk factors.

METHODS

This blinded cross-sectional study included 62 infants at six months of age divided into three independent groups: Group with no known risk factor (NRF), 28 full-terms with no risk factors; Low SES group (LSES):19 full-terms classified as low socioeconomic status and no biological risk; Very preterm group (VPT), 15 very preterm infants at six months corrected age and no environmental risk. Infants were placed in a reclined baby chair at 45°, and a malleable and unfamiliar object was presented to the infant at 5-second intervals to elicit reaching movements.

RESULTS

Infants from LSES presented reaching duration (p = 0.032, Cohen's f = 0.349) and movement unit (p = 0.033, Cohen's f = 0.351) significantly higher than VPT group. Horizontal hand orientation was moderately associated with infants at environmental risk (p = 0.031; Cramer's V = 0.30).

CONCLUSION

Infants of low socioeconomic status perform less functional reaching movements than very preterm infants at six months corrected age. Socioeconomic status may impact more on reaching skills than biological risk. Given the importance of reaching for infant development, low-cost public health strategies are needed to identify possible delays.

Interweaving social and manipulative development in early infancy: Some direction for infant caregiving

Early infancy has been neglect not having the best opportunities to promote social motor and cognitive development. The maturational concept considering young infants as passive beings provide a misguided view of the developmental process. The human infant is an active being from the very beginning of life. In the social and physical world, they can, by observing and imitating, perform complex actions involving different motor behaviours. In the present review we argue that imitation and manipulative actions are integrated in Expressive Action System (Reed, 1996) where baby-caregiver social interaction is the link between the use and exploration of objects in the world. We present evidence that neonatal imitation and manipulation activities are connected and thus, we propose stimulation practices based in seminal experimental designs where infants should be positioned in favourable postures to observe others acting in the world. This will have an impact on the way that early infants understand the social world and the chain of actions possible in this environment.

Motor atypicalities in infancy are associated with general developmental level at 2 years, but not autistic symptoms

LAY ABSTRACT

Atypicalities in motor functioning are often observed in later born infant siblings of children with autism spectrum disorder. The goal of our study was to investigate motor functioning in infants with and without familial history of autism spectrum disorder. Specifically, we investigated how infants catch a ball that is rolling toward them following a non-straight path, a task that requires both efficient planning and execution. Their performance was measured using detailed three-dimensional motion capture technology. We found that several early motor functioning measures were different in infants with an older autistic sibling compared to controls. However, these early motor measures were not related to autistic symptoms at the age of 2 years. Instead, we found that some of the early motor measures were related to their subsequent non-social, general development. The findings of our study help us understand motor functioning early in life and how motor functioning is related to other aspects of development.

Play with objects in children with arthrogryposis: Effects of intervention with the Playskin Lift™ exoskeletal garment

Children with arthrogryposis multiplex congenita (AMC) often exhibit arm movement impairments that can negatively impact activities of daily living, such as reaching, object exploration, object play, and self-care. This study evaluated the effects of intervention involving the Playskin Lift™ (Playskin) exoskeletal garment on arm function during object play for children with AMC. Seventeen children with AMC (5 males; 6-35 months at the beginning of the study) were tested in their homes biweekly with and without the Playskin throughout a 1-month Baseline, 4-month Intervention, and 1-month Post-Intervention. Within sessions (assistive effects), children contacted and manipulated objects more while wearing the Playskin; they also showed greater intensity, complexity, and variability of behaviors performed during free play, as well as increased play space and reduced number of compensatory arm and trunk flings to facilitate reaching. Across time (rehabilitative effects), children significantly improved their visual-manual coupling as well as their ability to lift objects from a surface and to manipulate objects using one hand; in addition, children exhibited greater multimodality, variability, and intensity of their play behaviors. Current results suggest the Playskin Lift™ may serve as an effective assistive and rehabilitative device to improve play for children with arm movement impairments.

The Two-Arm Coordination Test: Maturation of Bimanual Coordination in Typically Developing Children and Deficits in Children with Unilateral Cerebral Palsy

Background: Tools to assess bimanual coordination are scant. We aimed to: 1) provide normative data of maturation of bimanual coordination in tipically developing (TD) children measured by the Two Arm Coordination Test (TACT), and 2) validate the TACT as an instrument to specifically discriminate impairment of bimanual coordination in children with unilateral cerebral palsy (UCP). Procedure: Cross-sectional observational study. 252 TD children and 26 children with UCP performed 8 trials of TACT (following a star pattern with a pointer steered by coordinated movements of both arms). Number of errors and time were combined in a performance index of motor learning.Results: In TD children, bimanual coordination improved with age (F(7,244)=36.888, p<.001). Children with UCP had a poorer bimanual coordination than TD children (all t>24.25, all p<.01). TACT scores were correlated moderately to manual dexterity and manual ability (all r>-.452, all p<.039), showing the capacity of the TACT to provide information on different aspects of hand function. Conclusion: TACT is a valid instrument to assess bimanual coordination.

Reaching skills of infants born very preterm predict neurodevelopment at 2.5 years

The purpose was to investigate associations between quality of reaching for moving objects at 8 months corrected age and neurodevelopment at 2.5 years in children born very preterm (gestational age (GA), 24-31 weeks). Thirtysix infants were assessed while reaching for moving objects. The movements were recorded by a 3D motion capture system. Reaching parameters included aiming, relative length of the reach, number of movement units, proportion of bimanual coupled reaches and number of hits. Neurodevelopment was assessed at 2.5 years by the Bayley Scales of Infant Development III. There were strong associations between infant reaching kinematics and neurodevelopment of cognition and language but the patterns differed: in children born extremely preterm (GA < 28 weeks), planning and control of reaching was strongly related to outcome, while in children born very preterm (GA 28-31 weeks) number of hits and bimanual strategies were of greater relevance. In conclusion, for extremely preterm infants, basic problems on how motion information is incorporated with action planning prevail, while in very preterm infants the coordination of bimanual reaches is more at the focus. We conclude that the results reflect GA related differences in neural vulnerability and that early motor coordination deficits have a cascading effect on neurodevelopment.

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

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

Quantifying infant physical interactions using sensorized toys in a natural play environment

Infants with developmental delays must be detected early in their development to minimize the progression of motor and neurological impairments. Our objective is to quantify how sensorized toys in a natural play environment can promote infant-toy physical interactions. We created a hanging elephant toy, equipped with an inertial measurement unit (IMU), a pressure transducer, and multiple feedback sensors, to be a hand-grasping toy. We used a 3 DoF robotic model with inputs from the IMU to calculate multiple kinematic metrics and an equation to calculate haptic metrics from the pressure transducer. Six typical infants were tested in the gym set-up. Three infants interacted with the toy for more than half the trial time. The youngest infant exhibited the largest toy displacement with ΔD = 27.6 cm, while the oldest infant squeezed the toy with the largest mean pressure of 4.5 kPa. More data on on both typical and atypical infants needs to be collected. After testing atypical infants in the SmarToyGym set-up, we will be able to identify interaction metrics that differentiate atypical and typical infants.

The Impact of Segmental Trunk Support on Posture and Reaching While Sitting in Healthy Adults

The authors investigated postural and arm control in seated reaches while providing trunk support at midribs and pelvic levels in adults. Kinematics and electromyography of the arm and ipsiliateral and contralateral paraspinal muscles were examined before and during reaching. Kinematics remained constant across conditions, but changes were observed in neuromuscular control. With midribs support, the ipsilateral cervical muscle showed either increased anticipatory activity or earlier compensatory muscle responses, suggesting its major role in head stabilization. The baseline activity of bilateral lumbar muscles was enhanced with midribs support, whereas with pelvic support, the activation frequency of paraspinal muscles increased during reaching. The results suggest that segmental trunk support in healthy adults modulates ipsilateral or contralateral paraspinal activity while overall kinematic outputs remain invariant.

Development, and construct validity and internal consistency of the Grasp and Reach Assessment of Brisbane (GRAB) for infants with asymmetric brain injury

INTRODUCTION

Infants with asymmetric brain injury (asymBI) are at high risk of Unilateral Cerebral Palsy (UCP). The Grasp and Reach Assessment of Brisbane (GRAB) was developed to detect asymmetries in unimanual/bimanual upper limb (UL) reach and grasp behaviours in infants with asymBI. This study reports the development of the GRAB and evaluates its construct validity and internal consistency.

MATERIAL AND METHODS

Prospective study of twenty four infants with asymBI and twenty typically developing (TD) infants at 18 weeks corrected age (C.A.) in a structured play session. Three different coloured toys were presented at the midline in a block design of six 30-s trials of toy presentation, separated by five 30-s trials of no toy presentation. The number and duration of: (i) unimanual contacts; (ii) unimanual grasps; (iii) bimanual midline grasps; and (iv) duration of other unimanual behaviours (e.g. prehensile movements and transport phase) were measured. An Asymmetry Index (AI) was calculated to determine asymmetries between ULs. Possible AI values ranged from 0 to 100%, indicating proportion of toy presentation time that unimanual behaviours were asymmetric between ULs. Internal consistency of both the Time Phase (TP) and Toy Colour Phase (TCP) test items were determined by calculating Cronbach's alpha coefficients. Each assessment occasion was split into six TPs and two TCPs; whereby one TP comprised one 30-s trial of one toy presentation and one TCP comprised two 30-s trials of the same toy presentation.

RESULTS

For TP, seven out of nine unimanual behaviours and two out of three bimanual behaviours demonstrated strong internal consistency (Cronbach's alpha coefficients 0.72-0.89). No unimanual activity demonstrated the strongest IC (0.89). For TCP, six out of nine unimanual behaviours demonstrated strong IC (0.73-0.82). Number of unimanual contacts and duration of unimanual prehensile movements demonstrated the strongest IC (0.82). Duration of unimanual contribution to hands at midline and duration of bimanual midline behaviour demonstrated the weakest IC for both TP and TCP (0.46-0.50). For unimanual contacts, the asymBI group were more asymmetric between ULs (mean AI=50%) compared to the TD group (mean AI=30%). For unimanual grasps, both groups were similarly asymmetric (both mean AI=40%). The TD group were almost twice as likely to demonstrate bimanual grasps as the asymBI group (incidence rate ratio IRR 1.9, 95% CI 1.4 to 2.5, p<0.001). Infants with asymBI were less likely to use the impaired UL compared to the unimpaired UL for grasping (IRR 0.6, 95% CI 0.5 to 0.8, p<0.001); and used the impaired UL for a shorter proportion of time compared to the unimpaired UL for grasping (mean difference -9.1%, 95% CI -16.6 to -1.7, p=0.02).

CONCLUSIONS

The GRAB is a criterion-referenced research measure that detects and quantifies the presence or absence of unimanual and bimanual reach and grasp behaviours at 18 weeks C.A. in infants at risk of UCP. The GRAB demonstrated moderate to strong construct validity and strong IC within an assessment occasion. There was no toy preference or warm-up effect for TP or TCP for either group; confirming that the GRAB is a consistent measure across toy presentations within an assessment occasion. In this study, the GRAB identified that infants with asymBI demonstrated a paucity of bimanual grasping compared to TD infants; and demonstrated asymmetric unimanual grasping between ULs at 18 weeks C.A.

An Embodied Account of Early Executive-Function Development

The importance of executive functioning for later life outcomes, along with its potential to be positively affected by intervention programs, motivates the need to find early markers of executive functioning. In this study, 18-month-olds performed three executive-function tasks-involving simple inhibition, working memory, and more complex inhibition-and a motion-capture task assessing prospective motor control during reaching. We demonstrated that prospective motor control, as measured by the peak velocity of the first movement unit, is related to infants' performance on simple-inhibition and working memory tasks. The current study provides evidence that motor control and executive functioning are intertwined early in life, which suggests an embodied perspective on executive-functioning development. We argue that executive functions and prospective motor control develop from a common source and a single motive: to control action. This is the first demonstration that low-level movement planning is related to higher-order executive control early in life.

Effect of Segmental Trunk Support on Posture and Reaching in Children With Cerebral Palsy

PURPOSE

To test the effects of segmental trunk support on seated postural and reaching control in children with cerebral palsy.

METHODS

Seventeen children (age range 2-15 y, Gross Motor Function Classification System levels III-V) were classified with the Segmental Assessment of Trunk Control into mild (complete trunk control/lower lumbar deficits), moderate (thoracic/upper lumbar deficits), and severe (cervical/upper thoracic deficits). Postural and arm kinematics were measured while reaching with trunk support at axillae, mid-ribs, or pelvis.

RESULTS

Children in the mild group did not display changes in posture or reaching across conditions. The moderately involved group showed decrements in postural and reaching performance with pelvic compared with higher supports (P < .01). Children in the severe group were unable to maintain posture with pelvic support and showed postural deficiencies with mid-ribs compared with axillae support (P < .01).

CONCLUSIONS

Children with cerebral palsy and trunk dysfunction demonstrate improved motor performance when the external assistance matches their intrinsic level of trunk control.

Characterization and intervention for upper extremity exploration & reaching behaviors in infancy

This article aims to: 1) highlight general exploration, reaching, and object exploration behaviors as key activities of daily living in infancy, 2) describe how knowledge of early warning signs for these behaviors may improve early assessment, and 3) discuss interventions that may advance performance of these behaviors. Early intervention should focus on improving performance of these behaviors because: a) these early, interrelated upper extremity behaviors serve an integral role in global learning and development in infancy, b) among at-risk populations, differences have been observed in the quantity and quality of performance of these behaviors and, in many cases, these differences are associated with related perceptual-motor and cognitive delays. This article highlights how early assessment and intervention can target these key early behaviors in populations at risk for upper extremity disabilities, such as those born preterm, with Down syndrome, brachial plexus palsy, or arthrogryposis multiplex congentia.

The development of trunk control and its relation to reaching in infancy: a longitudinal study

The development of reaching is crucially dependent on the progressive control of the trunk, yet their interrelation has not been addressed in detail. Previous studies on seated reaching evaluated infants during fully supported or unsupported conditions; however, trunk control is progressively developed, starting from the cervical/thoracic followed by the lumbar/pelvic regions for the acquisition of independent sitting. Providing external trunk support at different levels to test the effects of controlling the upper and lower regions of the trunk on reaching provides insight into the mechanisms by which trunk control impacts reaching in infants. Ten healthy infants were recruited at 2.5 months of age and tested longitudinally, until 8 months. During the reaching test, infants were placed in an upright seated position and an adjustable support device provided trunk fixation at pelvic and thoracic levels. Kinematic and electromyographic data were collected. Results showed that prior to independent sitting, postural instability was higher when infants were provided with pelvic compared to thoracic support. Associated reaches were more circuitous, less smooth and less efficient. In response to the instability, there was increased postural muscle activity and arm muscle co-activation. Differences between levels of support were not observed once infants acquired independent sitting. These results suggest that trunk control is acquired in a segmental sequence across the development of upright sitting, and it is tightly correlated with reaching performance.

Differences between late preterm and full-term infants: comparing effects of a short bout of practice on early reaching behavior

This study compared the effects of a short bout of practice on reaching behavior between late preterm and full-term infants at the onset of goal-directed reaching. Twelve late preterm infants and twelve full-term infants received reaching practice based on a serial schedule. Late preterm and full-term infants were assessed in 3.3±1.4 and 2.6±1.0 days after the onset of goal-directed reaching in two measures in a single day: immediately before practice (pre-test) and immediately after practice (post-test). During the assessments, the infants were placed in a baby chair and a rubber toy was presented at their midline within reaching distance for 2 min. Between assessments, the infants received practice of toy-oriented reaching in 3 activities repeated for approximately 4 min. The activities were elicited in a pre-established serial sequence and were applied by a physical therapist. During the pre-test, late preterm infants presented lower range of proximal adjustments, greater proportion of reaches with semi-open hand, and greater proportion of reaches without grasping than the full-term infants. During the post-test, late preterm infants presented greater motor variability of proximal adjustments, but explored and selected distal control and grasping outcomes less compared to the full-term group. Differences in reaching and gross motor behavior between late preterm and full-term infants can be found at the age of reaching onset. Practice provided new opportunities for late preterm infants to improve perception-action coupling to reach; however, relative to full-terms, they seemed less advanced in benefiting from the experience for more refined manual tasks.

Early influence of auditory stimuli on upper-limb movements in young human infants: an overview

Given that the auditory system is rather well developed at the end of the third trimester of pregnancy, it is likely that couplings between acoustics and motor activity can be integrated as early as at the beginning of postnatal life. The aim of the present mini-review was to summarize and discuss studies on early auditory-motor integration, focusing particularly on upper-limb movements (one of the most crucial means to interact with the environment) in association with auditory stimuli, to develop further understanding of their significance with regard to early infant development. Many studies have investigated the relationship between various infant behaviors (e.g., sucking, visual fixation, head turning) and auditory stimuli, and established that human infants can be observed displaying couplings between action and environmental sensory stimulation already from just after birth, clearly indicating a propensity for intentional behavior. Surprisingly few studies, however, have investigated the associations between upper-limb movements and different auditory stimuli in newborns and young infants, infants born at risk for developmental disorders/delays in particular. Findings from studies of early auditory-motor interaction support that the developing integration of sensory and motor systems is a fundamental part of the process guiding the development of goal-directed action in infancy, of great importance for continued motor, perceptual, and cognitive development. At-risk infants (e.g., those born preterm) may display increasing central auditory processing disorders, negatively affecting early sensory-motor integration, and resulting in long-term consequences on gesturing, language development, and social communication. Consequently, there is a need for more studies on such implications.

Long-term influences of a preterm birth on movement organization and side specialization in children at 4-8 years of age

This study explored upper-limb and head kinematics during unimanual goal-directed movements in children born preterm (PT) and full-term (FT) aged 4-8 years. Further, functional lateralization was investigated through side-specific kinematics and hand preference observations. Altogether, 141 children were included, divided into three sub-groups based on gestation week at birth (GW). Children born FT (38-41 GW) and moderately PT (33-35 GW) showed faster, smoother, and shorter movement trajectories than children born very PT (V-PT < 33 GW). Only children born FT expressed evident side differences that were characterized by smoother movements with the preferred side. Regarding hand preference, the children born V-PT showed increased rates of non-right-handedness compared with the other groups. Regardless of hand preference, the children born V-PT showed less well organized movements compared with the other groups. These findings suggest that spatio-temporal movement organization and side specialization at pre-/early school-age are affected by a PT birth, and more frequently so for children born before 33 GWs, indicating long-lasting influences on neuromotor development and specialization.

A modular sensorized mat for monitoring infant posture

We present a novel sensorized mat for monitoring infant's posture through the measure of pressure maps. The pressure-sensitive mat is based on an optoelectronic technology developed in the last few years at Scuola Superiore Sant'Anna: a soft silicone skin cover, which constitutes the mat, participates in the transduction principle and provides the mat with compliance. The device has a modular structure (with a minimum of one and a maximum of six sub-modules, and a total surface area of about 1 m2) that enables dimensional adaptation of the pressure-sensitive area to different specific applications. The system consists of on-board electronics for data collection, pre-elaboration, and transmission to a remote computing unit for analysis and posture classification. In this work we present a complete description of the sensing apparatus along with its experimental characterization and validation with five healthy infants.

The effect of a short bout of practice on reaching behavior in late preterm infants at the onset of reaching: a randomized controlled trial

The purpose of this study was to examine the effects of a short bout of practice on reaching behavior in late preterm infants at the onset of goal-directed reaching. The study was designed as a blind, three-arm parallel-group, randomized controlled, clinical trial. Thirty-six late preterm infants were recruited from a maternity hospital and allocated according to computer generated randomization into groups that received reaching practice based on either a blocked schedule, a serial schedule, or no practice. Practice consisted of a 4 min session of induced reaching using a toy in three activities guided by a physical therapist. The activities were elicited in separate blocks for the blocked practice group and in a pre-established order for the serial practice group. The control group stayed in the physical therapist's lap but was not stimulated to reach. The infants were assessed 3.3±1.4 days after the onset of goal-directed reaching in three tests: pre-test (immediately before practice), post-test (immediately after practice), and retention test (24 h after post-test). During assessments, the infants were seated in a baby chair and a toy was presented at his/her midline within reaching distance for 2 min. Changes in the number of reaches, proportions of uni/bimanual reaches and kinematic parameters of reaching were main outcome measures. From pre- to post-test, the amount of reaches and bimanual reaches increased in the serial practice group, but the increase was not maintained in the retention test. Kinematic parameters were not affected by practice. Changes in the reaching behavior of late preterm infants can be triggered after the first few minutes of toy-oriented experience based on a serial practice schedule. These changes are not consolidated one day later.

Ophthalmological outcome and visuospatial ability in very preterm children measured at 2.5 years corrected age

AIM

To investigate the ophthalmological outcome of very preterm children at 2.5 years corrected age (CA) and perform a test of visuospatial and cognitive abilities.

METHODS

A population-based, prospective study (LOVIS study) in Uppsala County, Sweden, comprised 111 very preterm children (<32 w gestational age [GA]) born between 1 January 2004 and 31 December 2007. Ophthalmic evaluations were undertaken in 98/109 children (89.9%) alive at 2.5 years. Spatial cognition was investigated with a test of five alternative blocks in 48 preterm and 25 term-born children.

RESULTS

Visual impairment, strabismus or refractive errors, were found in 12% of the children. None of the children were blind in both eyes. Logistic regression analyses revealed significant associations between strabismus and periventricular leucomalacia/intraventricular haemorrhage (OR 9.6, p = 0.025) and between refractive errors and severe retinopathy of prematurity (OR 9.8, p = 0.011) and GA (OR 0.763, p = 0.034). Oval and rectangular blocks were significantly more difficult to insert into a box for preterm than full-term children (p = 0.048 and 0.013, respectively). There was a significant correlation between total scores for the five blocks and GA at birth (p = 0.035).

CONCLUSION

Eye and visual problems were found in 12% of the preterm children at 30 months CA. Preterm children had difficulties with blocks of complex shapes.

Typical and atypical development of reaching and postural control in infancy

Successful reaching requires postural control, either by active regulation or by postural support. The present paper reviews literature on typical and atypical development of reaching and postural control during infancy. Typically, reaching movements end in grasping around 4 months of age. Initially, reaches are characterized by large variation, including many trajectory corrections. During the first year, the movements get increasingly straight and smooth. Reaching in low-risk preterm infants is initially characterized by advanced development, but minor impairments may emerge in the second half of infancy. In high-risk preterm infants, development of reaching is characterized by delay and non-optimal reaching performance. Typical development of postural adjustments is characterized by variation and an increasing ability to adapt the variable repertoire to the specifics of the situation. The latter is facilitated by an increasing role of anticipatory mechanisms in the second half of infancy. Atypically developing infants may have a reduced repertoire and usually have difficulties in adapting postural adjustments. In infancy, most reaching movements are performed during sitting. The postural challenge of sitting may interfere in particular with the development of reaching in atypically developing infants. The practical implications of this suggestion are discussed.

Segmental trunk control acquisition and reaching in typically developing infants

This study explored the influence of an external support at the thoracic and pelvic level of the trunk on the success of reaching, postural stability and reaching kinematics while infants reached for a toy. Seventeen infants (4-6 months) were clustered into two groups according to their trunk control assessed with the Segmental Assessment of Trunk Control. Major differences were seen between groups with pelvic support, whereas with thoracic support, all infants showed similar quality reaching behaviors. With the external pelvic support, infants who had acquired trunk control in the lumbar region were more accurate in their reaching movements (less movement time, improved straightness of reach, less movement units and increased path length per movement unit) and were more stable (decreased trunk and head displacement) during a reach than infants who had only acquired trunk control in the thoracic region. These results support the hypothesis that trunk control influences the quality of reaching behavior.