Atypical Motor Research Articles

The Structured Observation of Motor Performance in Infants has convergent and discriminant validity in preterm and term infants.

Methods are needed to evaluate the level of early motor development and quality of motor performance in infants. We examined the convergent and discriminant validity of the Structured Observation of Motor Performance in Infants (SOMP-I) for evaluating the level of motor development and quality of motor performance in preterm and term infants. A regional cohort of 111 preterm infants with a gestational age of <32 weeks and 72 healthy term born infants were assessed with the SOMP-I, at two, four, six and 10 months of corrected age. Convergent validity was analysed with a mixed model analysis of the motor performance over time. Discriminant validity was analysed with the Mann-Whitney U-test in groups with different neonatal characteristics. Convergent validity was supported, as the level of motor development increased with age and the quality of motor performance improved over time. The method discriminated for both level and quality between the preterm and the term infants. The preterm infants demonstrated different quality deficits regardless of the level of motor development. Convergent validity and discriminant validity of the SOMP-I were supported in preterm and term infants and facilitates early identification of infants with atypical motor development.

Auditory-motor rhythm synchronization in children with autism spectrum disorder

BackgroundAutism spectrum disorder (ASD) is characterized by difficulties in social and communication skills as well as atypical sensory perception and motor skills. Sensorimotor abilities such as auditory-motor integration are essential for social interaction and communication. The goal of this research was to investigate the development of auditory-motor rhythm synchronization for the first time in ASD versus typically-developing (TD) children. MethodsParticipants were 31 boys with ASD and 23 TD boys that were matched in age and IQ. Participants were tested on an auditory-motor rhythm synchronization task in which they tapped in synchrony with rhythms of varying metrical complexity. ResultsBoth children with ASD and TD performed similarly on this task and both groups performed better with age. ConclusionsThis work demonstrates that non-verbal rhythm synchronization is intact in ASD over the course of childhood development. This research serves to better understand sensorimotor interactions in ASD and to better define sensory phenotypes in ASD.

Children with cerebral palsy have altered oscillatory activity in the motor and visual cortices during a knee motor task

The neuroimaging literature on cerebral palsy (CP) has predominantly focused on identifying structural aberrations within the white matter (e.g., fiber track integrity), with very few studies examining neural activity within the key networks that serve the production of motor actions. The current investigation used high-density magnetoencephalography to begin to fill this knowledge gap by quantifying the temporal dynamics of the alpha and beta cortical oscillations in children with CP (age = 15.5 ± 3 years; GMFCS levels II–III) and typically developing (TD) children (age = 14.1 ± 3 years) during a goal-directed isometric target-matching task using the knee joint. Advanced beamforming methods were used to image the cortical oscillations during the movement planning and execution stages. Compared with the TD children, our results showed that the children with CP had stronger alpha and beta event-related desynchronization (ERD) within the primary motor cortices, premotor area, inferior parietal lobule, and inferior frontal gyrus during the motor planning stage. Differences in beta ERD amplitude extended through the motor execution stage within the supplementary motor area and premotor cortices, and a stronger alpha ERD was detected in the anterior cingulate. Interestingly, our results also indicated that alpha and beta oscillations were weaker in the children with CP within the occipital cortices and visual MT area during movement execution. These altered alpha and beta oscillations were accompanied by slower reaction times and substantial target matching errors in the children with CP. We also identified that the strength of the alpha and beta ERDs during the motor planning and execution stages were correlated with the motor performance. Lastly, our regression analyses suggested that the beta ERD within visual areas during motor execution primarily predicted the amount of motor errors. Overall, these data suggest that uncharacteristic alpha and beta oscillations within visuomotor cortical networks play a prominent role in the atypical motor actions exhibited by children with CP.

Presumed congenital infection by Zika virus: findings on psychomotor development - a case report

Abstract Introduction: the identification of Zika virus (ZikV) in the amniotic fluid, in the placenta and in newborns' brains suggests a neurotropism of this agent in the brain development, resulting in neuro-psycho-motor alterations. Thus, this present study reports the assessment of children diagnosed by a congenital infection, presumably by ZikV, followed-up at the Rehabilitation Center Prof. Ruy Neves Baptist at the Instituto de Medicina Integral Prof. Fernando Figueira (IMIP). Description: as proposed by the Ministry of Health, the following instruments were used to evaluate the neuro-motor functions of four children with microcephaly aged between three and four months: The Test of Infant Motor Performance (TIMP); the functional vision assessment; the manual function scale development; and the clinical evaluation protocol on pediatric dysphagia (PAD-PED). Discussion: the children evaluated presented atypical motor performance, muscle tone and spontaneous motricity which encompass the symmetry and the motion range of the upper and lower limbs proven to be altered. The functional vision showed alterations which can cause limitations in the performance of functional activities and the learning process. Regarding to the speech articulator's functions observed that the maturation and coordination of sucking, swallowing and breathing did not yet encounter the appropriate age maturity level.

Parents’ initial concerns about the development of their children later diagnosed with fragile X syndrome

ABSTRACTBackground Retrospective parental reports have often been used to identify the early characteristics of children later diagnosed with a developmental disorder.Method We applied this methodology to document 13 parents’ initial concerns about the development of their 17 children later diagnosed with fragile X syndrome (FXS). Parents were additionally asked about when they noticed the emergence of behavioural signs related to FXS.Results More than half of the parents reported initial concerns prior to the child’s first birthday, and in most cases it was atypical motor behaviours that caused the first concerns. Behavioural signs related to the FXS phenotype were also reported to be perceptible in the first year of the child’s life.Conclusions Due to limitations of retrospective parental questionnaires, we suggest that other methodologies, such as home video analysis, are needed to complement our understanding of the pathways of developmental disorders with late clinical onsets.

Coupling of online control and inhibitory systems in children with atypical motor development: A growth curve modelling study

IntroductionPrevious research indicates that children with Developmental Coordination Disorder (DCD) show deficits performing online corrections, an issue exacerbated by adding inhibitory constraints; however, cross-sectional data suggests that these deficits may reduce with age. Using a longitudinal design, the aim of the study presented here was to model the coupling that occurs between inhibitory systems and (predictive) online control in typically developing children (TDC) and in those with Developmental Coordination Disorder (DCD) over an extended period of time, using a framework of interactive specialization. We predicted that TDC would show a non-linear growth pattern, consistent with re-organisation in the coupling during the middle childhood period, while DCD would display a developmental lag. MethodA group of 196 children (111 girls and 85 boys) aged between 6 and 12years participated in the study. Children were classified as DCD according to research criteria. Using a cohort sequential design, both TDC and DCD groups were divided into age cohorts. Predictive (online) control was defined operationally by performance on a Double-Jump Reaching Task (DJRT), which was assessed at 6-month intervals over two years (5 time points in total). Inhibitory control was examined using an anti-jump condition of the DJRT paradigm whereby children were instructed to touch a target location in the hemispace opposite a cued location. ResultsFor the TDC group, model comparison using growth curve analysis revealed that a quadratic trend was the most appropriate fit with evidence of rapid improvement in anti-reach performance up until middle childhood (around 8–9years of age), followed by a more gradual rate of improvement into late childhood and early adolescence. This pattern was evident on both chronometric and kinematic measures. In contrast, for children with DCD, a linear function provided the best to fit on the key metrics, with a slower rate of improvement than controls. ConclusionWe conclude that children with DCD require a more extended period of development to effectively couple online motor control and executive systems when completing anti-reach movements, whereas TDC show rapid improvement in early and middle childhood. These group differences in growth curves are likely to reflect a maturational lag in the development of motor-cognitive networks in children with DCD.

Brief Report: Autism Symptoms in Infants with Fragile X Syndrome.

Fragile X syndrome (FXS) is the most common known genetic cause of autism spectrum disorder (ASD). Although 50-75 % of children with FXS meet ASD criteria, no studies have compared ASD symptoms in infants with FXS versus other high risk groups, such as siblings of children with ASD (ASIBs). Using the Autism Observation Scale for Infants, our findings indicate that 53 % of 12-month infants with FXS fall in the "at risk" category compared to 17 and 6 % for age-matched ASIBs and controls, respectively. Elevated atypical motor behaviors were associated with elevated risk for FXS. Cross-syndrome comparisons are essential to understanding the heterogeneity of ASD and identifying candidate markers that will facilitate differential diagnosis of ASD in genetic disorders such as FXS.

Value of pre-cue information for motor tasks performed by children with developmental coordination disorder (DCD)

People commonly use pre-cue information to advance and reduce the information processing time required for a motor task (e.g., motor planning). However, children with developmental coordination disorder (DCD) exhibit difficulties performing pre-cued goal-directed tasks. The purpose of the present study was to investigate the use of valid, neutral, and invalid pre-cue information for a goal-directed task. The participants were 11 children with DCD (mean age = 7.94 yrs.) and 11 typically developed (TD) age- and gender-matched children. The children with DCD exhibited delayed motor planning (e.g., reaction time) under the invalid condition compared to that of the TD children. The children with DCD used atypical strategies for motor execution and depended more on online corrections (e.g., increased deceleration time and movement units) to reach the target. These results suggest that children with DCD have difficulties handling unpredictable situations and that the use of atypical motor execution strategies did not affect movement time.

Impact of compensatory intervention in 6- to 18-month-old babies at risk of motor development delays

ABSTRACTPurpose: Research indicates that delayed motor development observed in the first years of life can be prevented through compensatory intervention programmes that provide proper care during this critical period of child development. Method: This study analysed the impact of a 12-week compensatory motor intervention programme on 32 babies with atypical motor development, characterising and correlating risk factors for developmental delays between the ages of 6 and 8 months. We conducted play activities that involved muscle stretching, improving muscle tone, sight and sound tracking, posture control in different situations, handling objects and movement. The aim was to allow babies to experience new movement situations and overcome challenges. Results: The results showed significant improvements in motor performance, reinforcing the positive effects of a contextualised approach that addresses the needs of developing children, as opposed to focusing solely on acquiring specific skills in early childhood.

Integrating New Technologies into the Treatment of CP and DCD

This paper examines how current understandings of childhood participation and motor development provide opportunities for using new technologies (such as virtual reality—VR) for children with neurodevelopmental disorders. Specifically, the International Classification of Functioning, Disability and Health is used to conceptualize the role of technology in treatment across body structures and body function, activity performance, and participation (WHO 2007, 2012). First, we review the particular motor control and learning mechanisms that have been implicated in children with atypical motor development, like DCD. This section will highlight avenues for targeted remediation. Next, VR-based rehabilitation systems are reviewed in relation to neurodevelopmental disorders, focusing first on CP and second on more recent applications for children with DCD. We describe the evolution of particular design innovations in virtual rehabilitation including recent advances using tangible interfaces, as well as other methods targeting cognitive function more specifically. Benefits of these various treatments will be viewed through the lens of current theory and evaluated at the level of child and family outcomes. Finally, we consider the broader aspects of the potential for technological innovation in rehabilitation and its impact on brain function, activity competence, and longer-term participation.

Longitudinal development of manual motor ability in autism spectrum disorder from childhood to mid-adulthood relates to adaptive daily living skills.

Many individuals with autism spectrum disorder (ASD) exhibit motor difficulties, but it is unknown whether manual motor skills improve, plateau, or decline in ASD in the transition from childhood into adulthood. Atypical development of manual motor skills could impact the ability to learn and perform daily activities across the life span. This study examined longitudinal grip strength and finger tapping development in individuals with ASD (n=90) compared to individuals with typical development (n=56), ages 5 to 40years old. We further examined manual motor performance as a possible correlate of current and future daily living skills. The group with ASD demonstrated atypical motor development, characterized by similar performance during childhood but increasingly poorer performance from adolescence into adulthood. Grip strength was correlated with current adaptive daily living skills, and Time 1 grip strength predicted daily living skills eight years into the future. These results suggest that individuals with ASD may experience increasingly more pronounced motor difficulties from adolescence into adulthood and that manual motor performance in ASD is related to adaptive daily living skills.

Upper trapezius muscle activity in healthy office workers: reliability and sensitivity of occupational exposure measures to differences in sex and hand dominance

Patterns of cervical muscle activity may contribute to overuse injuries in office workers. The purpose of this investigation was to characterise patterns of upper trapezius muscle activity in pain-free office workers using traditional occupational exposure measures and a modified Active Amplitude Probability Distribution Function (APDF), which considers only periods of active muscle contraction. Bilateral trapezius muscle activity was recorded in 77 pain-free office workers for 1–2 full days in their natural work environment. Mean amplitude, gap frequency, muscular rest and Traditional and Active APDF amplitudes were calculated. All measures demonstrated fair to substantial reliability. Dominant muscles demonstrated higher amplitudes of activity and less muscular rest compared to non-dominant, and women demonstrated less muscular rest with no significant difference in amplitude assessed by Active APDF compared to men. These findings provide normative data to identify atypical motor patterns that may contribute to persistence or recurrence of neck pain in office workers.Practitioner Summary: Upper trapezius muscle activity was characterised in a large cohort of pain-free workers using electromyographic recordings from office environments. Dominant muscles demonstrated higher activity and less rest than non-dominant, and women demonstrated less rest than men. Results may be used to identify atypical trapezius muscle activity in office workers.

Modeling the Maturation of Grip Selection Planning and Action Representation: Insights from Typical and Atypical Motor Development.

We investigated the purported association between developmental changes in grip selection planning and improvements in an individual’s capacity to represent action at an internal level [i.e., motor imagery (MI)]. Participants were groups of healthy children aged 6–7 years and 8–12 years respectively, while a group of adolescents (13–17 years) and adults (18–34 years) allowed for consideration of childhood development in the broader context of motor maturation. A group of children aged 8–12 years with probable DCD (pDCD) was included as a reference group for atypical motor development. Participants’ proficiency to generate and/or engage internal action representations was inferred from performance on the hand rotation task, a well-validated measure of MI. A grip selection task designed to elicit the end-state comfort (ESC) effect provided a window into the integrity of grip selection planning. Consistent with earlier accounts, the efficiency of grip selection planning followed a non-linear developmental progression in neurotypical individuals. As expected, analysis confirmed that these developmental improvements were predicted by an increased capacity to generate and/or engage internal action representations. The profile of this association remained stable throughout the (typical) developmental spectrum. These findings are consistent with computational accounts of action planning that argue that internal action representations are associated with the expression and development of grip selection planning across typical development. However, no such association was found for our sample of children with pDCD, suggesting that individuals with atypical motor skill may adopt an alternative, sub-optimal strategy to plan their grip selection compared to their same-age control peers.

Atypical within- and between-hemisphere motor network functional connections in children with developmental coordination disorder and attention-deficit/hyperactivity disorder.

Developmental coordination disorder (DCD) and attention-deficit hyperactivity disorder (ADHD) are highly comorbid neurodevelopmental disorders; however, the neural mechanisms of this comorbidity are poorly understood. Previous research has demonstrated that children with DCD and ADHD have altered brain region communication, particularly within the motor network. The structure and function of the motor network in a typically developing brain exhibits hemispheric dominance. It is plausible that functional deficits observed in children with DCD and ADHD are associated with neurodevelopmental alterations in within- and between-hemisphere motor network functional connection strength that disrupt this hemispheric dominance. We used resting-state functional magnetic resonance imaging to examine functional connections of the left and right primary and sensory motor (SM1) cortices in children with DCD, ADHD and DCD + ADHD, relative to typically developing children. Our findings revealed that children with DCD, ADHD and DCD + ADHD exhibit atypical within- and between-hemisphere functional connection strength between SM1 and regions of the basal ganglia, as well as the cerebellum. Our findings further support the assertion that development of atypical motor network connections represents common and distinct neural mechanisms underlying DCD and ADHD. In children with DCD and DCD + ADHD (but not ADHD), a significant correlation was observed between clinical assessment of motor function and the strength of functional connections between right SM1 and anterior cingulate cortex, supplementary motor area, and regions involved in visuospatial processing. This latter finding suggests that behavioral phenotypes associated with atypical motor network development differ between individuals with DCD and those with ADHD.

Information Processing and Motor Control in Down Syndrome

Extensive research on the motor performance of individuals with intellectual disabilities (ID) and more specifically individuals with Down syndrome (DS) reflects performance deficits in physical and motor functioning. Earlier study, indicated that low levels of physical function and deficiencies in sensory processing, memory consolidation, and postural control impact their ability to acquire and perform motor skills under variable environmental contexts. In addition, indicated that movements are often uncoordinated, slower, variable and hesitant in initiation, while other researchers reported longer movements and reaction times as well as difficulties in balance and postural control. Further limitations in spontaneous or symbolic play and limited opportunities to practice motor skills were observed in school and/or community settings, primarily during their developmental years. It is apparent that these individuals display delayed motor development and atypical motor functioning, which may be attributed to structural differences in the neurological system, delayed brain development, and a compromised somatosensory system.

Speech motor planning and execution deficits in early childhood stuttering.

BackgroundFive to eight percent of preschool children develop stuttering, a speech disorder with clearly observable, hallmark symptoms: sound repetitions, prolongations, and blocks. While the speech motor processes underlying stuttering have been widely documented in adults, few studies to date have assessed the speech motor dynamics of stuttering near its onset. We assessed fundamental characteristics of speech movements in preschool children who stutter and their fluent peers to determine if atypical speech motor characteristics described for adults are early features of the disorder or arise later in the development of chronic stuttering.MethodsOrofacial movement data were recorded from 58 children who stutter and 43 children who do not stutter aged 4;0 to 5;11 (years; months) in a sentence production task. For single speech movements and multiple speech movement sequences, we computed displacement amplitude, velocity, and duration. For the phrase level movement sequence, we computed an index of articulation coordination consistency for repeated productions of the sentence.ResultsBoys who stutter, but not girls, produced speech with reduced amplitudes and velocities of articulatory movement. All children produced speech with similar durations. Boys, particularly the boys who stuttered, had more variable patterns of articulatory coordination compared to girls.ConclusionsThis study is the first to demonstrate sex-specific differences in speech motor control processes between preschool boys and girls who are stuttering. The sex-specific lag in speech motor development in many boys who stutter likely has significant implications for the dramatically different recovery rates between male and female preschoolers who stutter. Further, our findings document that atypical speech motor development is an early feature of stuttering.

Sensorized toys for measuring manipulation capabilities of infants at home.

Preterm infants, i.e. babies born after a gestation period shorter than 37 weeks, spend less time exploring objects. The quantitative measurement of grasping actions and forces in infants can give insights on their typical or atypical motor development. The aim of this work was to test a new tool, a kit of sensorized toys, to longitudinally measure, monitor and promote preterm infants manipulation capabilities with a purposive training in an ecological environment. This study presents preliminary analysis of grasping activity. Three preterm infants performed 4 weeks of daily training at home. Sensorized toys with embedded pressure sensors were used as part of the training to allow quantitative analysis of grasping (pressure and acceleration applied to toys while playing). Each toy was placed on the midline, while the infant was in supine position. Preliminary data show differences in the grasping parameters in relation to infants age and the performed daily training. Ongoing clinical trial will allow a full validation of this new tool for promoting object exploration in preterm infants.

Motor skills of 5-year-old children who underwent early cardiac surgery.

Aims To describe the motor proficiency of 5-year-old children who underwent early infant cardiac surgery and had atypical infant gross motor development. To identify risk factors for motor dysfunction at 5 years of age. A total of 33 children (80.5% participation rate) were re-assessed by a physiotherapist blinded to the diagnosis and previous clinical course, using standardised motor assessment tools. Motor proficiency was categorised as below average or well below average in 41% of the study patients. Approximately 30% of the cohort had balance deficits. Motor abilities at 4 months and 2 years of age were associated with motor proficiency at age 5; however, atypical motor development in infancy was not predictive of below-average or well below-average scores at age 5. Risk factors associated with motor ability at age 5 included respiratory support and intensive care length of stay in the 1st year of life, asymmetrical crawling in infancy, and cyanotic CHD at age 5. Despite differences from other reported studies in terms of cohort diagnoses and age at surgery, the rate of motor dysfunction was similar, with rates much higher than expected in typical children. Further assessment is needed in later childhood to determine the significance of these findings.

Intermittent reductions in respiratory neural activity elicit spinal TNF-α-independent, atypical PKC-dependent inactivity-induced phrenic motor facilitation.

In many neural networks, mechanisms of compensatory plasticity respond to prolonged reductions in neural activity by increasing cellular excitability or synaptic strength. In the respiratory control system, a prolonged reduction in synaptic inputs to the phrenic motor pool elicits a TNF-α- and atypical PKC-dependent form of spinal plasticity known as inactivity-induced phrenic motor facilitation (iPMF). Although iPMF may be elicited by a prolonged reduction in respiratory neural activity, iPMF is more efficiently induced when reduced respiratory neural activity (neural apnea) occurs intermittently. Mechanisms giving rise to iPMF following intermittent neural apnea are unknown. The purpose of this study was to test the hypothesis that iPMF following intermittent reductions in respiratory neural activity requires spinal TNF-α and aPKC. Phrenic motor output was recorded in anesthetized and ventilated rats exposed to brief intermittent (5, ∼1.25 min), brief sustained (∼6.25 min), or prolonged sustained (30 min) neural apnea. iPMF was elicited following brief intermittent and prolonged sustained neural apnea, but not following brief sustained neural apnea. Unlike iPMF following prolonged neural apnea, spinal TNF-α was not required to initiate iPMF during intermittent neural apnea; however, aPKC was still required for its stabilization. These results suggest that different patterns of respiratory neural activity induce iPMF through distinct cellular mechanisms but ultimately converge on a similar downstream pathway. Understanding the diverse cellular mechanisms that give rise to inactivity-induced respiratory plasticity may lead to development of novel therapeutic strategies to treat devastating respiratory control disorders when endogenous compensatory mechanisms fail.

Clinical course of primary progressive aphasia: clinical and FDG-PET patterns.

Primary progressive aphasia (PPA) may be the onset of several neurodegenerative diseases. This study evaluates a cohort of patients with PPA to assess their progression to different clinical syndromes, associated factors that modulate this progression, and patterns of cerebral metabolism linked to different clinical evolutionary forms. Thirty-five patients meeting PPA criteria underwent a clinical and neuroimaging (18)F-Fluorodeoxyglucose PET evaluation. Survival analysis was performed using time from clinical onset to the development of a non-language symptom or deficit (PPA-plus). Cerebral metabolism was analyzed using Statistical Parametric Mapping. Patients classified into three PPA variants evolved to atypical parkinsonism, behavioral disorder and motor neuron disease in the agrammatic variant; to behavioral disorder in the semantic; and to memory impairment in the logopenic. Median time from the onset of symptoms to PPA-plus was 36 months (31-40, 95 % confidence interval). Right laterality, and years of education were associated to a lower risk of progression, while logopenic variant to a higher risk. Different regions of hypometabolism were identified in agrammatic PPA with parkinsonism, motor neuron disease and logopenic PPA-plus. Clinical course of PPA differs according to each variant. Left anterior temporal and frontal medial hypometabolism in agrammatic variant is linked to motor neuron disease and atypical parkinsonism, respectively. PPA variant, laterality and education may be associated to the risk of progression. These results suggest the possibility that clinical and imaging data could help to predict the clinical course of PPA.