Multisensory adaptation of spatial-to-motor transformations in children with developmental coordination disorder

Motor and visuospatial processing profile in a cross-conditions study: A comparison between developmental coordination disorder and nonverbal learning disability

BACKGROUND

Neurodevelopmental conditions often exhibit overlapping symptoms, posing challenges for differential diagnosis. Developmental Coordination Disorder (DCD) manifests as fundamental motor impairments, often along with co-occurring visuospatial difficulties. Nonverbal Learning Disorder (NLD) features visuospatial core challenges, with a less consistent characterization of its motor profile. Strikingly, to date no study has directly compared DCD and NLD profiles.

AIMS

The present study aimed to analyze whether DCD and NLD share any characteristics by contrasting their motor and visuospatial performances, comparing them with non-diagnosed (ND) peers.

METHODS AND PROCEDURES

A total of 102 participants (8-16 years; DCD N = 29, NLD N = 29, ND N = 44) completed motor and visuospatial tasks. The groups' performance was compared, and the discriminatory power of the measures administered was analyzed.

OUTCOMES AND RESULTS

Our findings support the substantial motor and visuospatial impairments in DCD and NLD, respectively. Regarding diagnostic efficacy, motor and visuospatial tasks effectively differentiated DCD or NLD from ND, with specificities related to each condition. Balance, and to a lesser extent, Spatial Processing revealed significant predictive power in distinguishing between DCD and NLD.

CONCLUSIONS AND IMPLICATIONS

Our results revealed cross-disorder similarities and highlighted specific hallmarks, corroborating the need of a comprehensive motor and visuospatial assessment for distinguishing between DCD and NLD.

Motor competence is related to acquisition of error-based but not reinforcement learning in children ages 6 to 12

Background

An essential component of childhood development is increasing motor competence. Poor motor learning is often thought to underlie impaired motor competence, but this link is unclear in previous studies.

Aims

Our aim was to test the relationship between motor competence and motor learning in the acquisition phase. Both reinforcement learning (RL) and error-based learning (EBL) were tested. We hypothesized that slower RL and slower EBL acquisition rates would relate to lower motor competence.

Methods and procedures

Eighty-six participants ages 6-12 performed a target throwing task under RL and EBL conditions. The Movement Assessment Battery for Children - 2nd edition (MABC-2) provided a measure of motor competence. We assessed EBL and RL acquisition rates, baseline variability, and baseline bias from the throwing task.

Outcomes and results

In a multiple linear regression model, baseline variability (β = -0.49, p = <0.001) and the EBL acquisition rate (β = -0.24, p = 0.018) significantly explained the MABC-2 score. Participants with higher baseline variability and slower EBL acquisition had lower motor competence scores. The RL acquisition rate was independent of MABC-2 score suggesting that RL may be less of a contributor to poor motor competence.

Conclusions and implications

Children with slower EBL acquisition had lower motor competence scores but RL acquisition was unrelated to the level of motor competence. Emphasizing the unrelated reinforcement mechanisms over error-based mechanisms during motor skill interventions may help children with poor motor competence better acquire new motor skills.

"Picture this from there": spatial perspective-taking in developmental visuospatial disorder and developmental coordination disorder

Introduction

Either Developmental Visuospatial Disorder (DVSD) and Developmental Coordination Disorder (DCD) present with difficulties in visuospatial processing, even though entailing different degrees of impairment. Among the visuospatial domain, spatial perspective taking is essential to interact with the environment and is significantly involved in many daily activities (e.g., environment navigation and spatial orienting). Notwithstanding, no previous studies have investigated this spatial domain in children with DVSD and limited evidence is available regarding DCD. Consistent with a transdiagnostic approach, the first goal of the present study was to compare spatial perspective taking abilities of these groups, also including a control group of not diagnosed peers (ND). Secondly, the role of different fine-motor and visuo-spatial predictors on the spatial perspective taking performance was considered.

Method

A total of 85 participants (DVSD = 26; DCD = 26; ND = 33), aged between 8 and 16 years old, were included in the study. Tasks assessing spatial perspective taking, fine-motor, visual imagery, and mental rotation skills, as well as visuo-spatial working memory were administered.

Results and Discussion

Overall, our results confirmed weaknesses in spatial perspective taking in both clinical groups, with the DVSD obtaining the lowest scores. Similarities and differences in the predictors accounting for the performance in the spatial perspective taking task emerged, suggesting the possible employment of different fine-motor or visuospatial strategies by group. Findings are discussed considering the potential impact they may have both in research and clinical practice.

Visuomotor adaptation, internal modelling, and compensatory movements in children with developmental coordination disorder

BACKGROUND

Developmental coordination disorder (DCD) is one of the most prevalent developmental disorders in school-aged children. The mechanisms and etiology underlying DCD remain somewhat unclear. Altered visuomotor adaptation and internal model deficits are discussed in the literature.

AIMS

The study aimed to investigate visuomotor adaptation and internal modelling to determine whether and to what extent visuomotor learning might be impaired in children with DCD compared to typically developing children (TD). Further, possible compensatory movements during visuomotor learning were explored.

METHODS AND PROCEDURES

Participants were 12 children with DCD (age 12.4 ± 1.8, four female) and 18 age-matched TD (12.3 ± 1.8, five female). Visuomotor learning was measured with the Motor task manager. Compensatory movements were parameterized by spatial and temporal variables.

OUTCOMES AND RESULTS

Despite no differences in visuomotor adaptation or internal modelling, significant main effects for group were found in parameters representing movement accuracy, motor speed, and movement variability between DCD and TD.

CONCLUSIONS AND IMPLICATIONS

Children with DCD showed comparable performances in visuomotor adaptation and internal modelling to TD. However, movement variability was increased, whereas movement accuracy and motor speed were reduced, suggesting decreased motor acuity in children with DCD.

Auditory-Perceptual and Auditory-Motor Timing Abilities in Children with Developmental Coordination Disorder: A Scoping Review

Developmental coordination disorder (DCD) remains largely underdiagnosed and masked by other co-occurring conditions. The aim of this study was to (1) provide the first review of research regarding auditory-motor timing and synchronization abilities in children with DCD and (2) examine whether reduced motor performance may be associated with difficulties in auditory perceptual timing. The scoping review was carried out across five major databases (MEDLINE, Embase, PsycINFO, CINAHL, and Scopus) in accordance with the PRISMA-ScR guidelines. Studies were screened by two independent reviewers against the inclusion criteria, without publication date restrictions. From an initial return of 1673 records, 16 articles were included in the final review and synthesized based on the timing modality studied (i.e., auditory-perceptual, motor, or auditory-motor). Results suggest that children with DCD have difficulties with rhythmic movements both with and without external auditory cues and further indicate that variability in and slowness of motor response are key characteristics of DCD, regardless of the experimental task. Importantly, our review highlights a significant gap in the literature regarding auditory perceptual abilities in DCD. In addition to testing auditory perception, future studies should compare the performance of children with DCD on paced and unpaced tasks to determine whether auditory stimuli contribute to a more or less stable performance. This knowledge may inform future therapeutic interventions.

Combined action observation and motor imagery facilitates visuomotor adaptation in children with developmental coordination disorder

The internal modelling deficit (IMD) hypothesis suggests that motor control issues associated with Developmental Coordination Disorder (DCD) are the result of impaired predictive motor control. In this study, we examined the benefits of a combined action observation and motor imagery (AO + MI) intervention designed to alleviate deficits in internal modelling and improve eye-hand coordination during a visuomotor rotation task. Twenty children with DCD were randomly assigned to either an AO + MI group (who watched a video of a performer completing the task whilst simultaneously imagining the kinaesthetic sensations associated with action execution) or a control group (who watched unrelated videos involving no motor content). Each group then attempted to learn a 90° visuomotor rotation while measurements of completion time, eye-movement behaviour and movement kinematics were recorded. As predicted, after training, the AO + MI group exhibited quicker completion times, more target-focused eye-movement behaviour and smoother movement kinematics compared to the control group. No significant after-effects were present. These results offer further support for the IMD hypothesis and suggest that AO + MI interventions may help to alleviate such deficits and improve motor performance in children with DCD.

A Perception-Action Approach to Understanding Typical and Atypical Motor Development

In this chapter, we ask two questions. First, can the study of the perception-action system across time offer a useful model for understanding motor development? Second, can the study of the perception-action system in children with developmental coordination disorder (DCD) inform our understanding of atypical as well as typical motor development? We begin by describing the dynamical systems perspective and a control-theoretic approach that together provide the conceptual framework for our paradigms, methodology, and interpretation of our experiments. Our experimental strategy has been to perturb one or more sensory systems and observe the effect on the motor system. The majority of the chapter explains how we employed two principal perturbation strategies: (1) removing or adding a static source of sensory information believed to be salient to the task at hand and (2) enhancing a dynamic source of sensory information either implicitly or explicitly. These strategies were employed in three different action systems: posture; rhythmic interlimb coordination, and goal-directed reaching and drawing. After synthesizing our findings, we conclude by addressing the original questions and offering future directions. In brief, we consider that perception-action coupling is an underlying mechanism/foundation/constraint of motor development in the sense that the ongoing processing of sensations and the planning and execution of movements are how the brain produces goal-directed movements. Therefore, a better understanding of how this coupling changes or adapts over time has much to offer as to how motor behavior develops across the lifespan, both typically and atypically.

Cognitive and neuroimaging findings in developmental coordination disorder: new insights from a systematic review of recent research

AIM

To better understand the neural and performance factors that may underlie developmental coordination disorder (DCD), and implications for a multi-component account.

METHOD

A systematic review of the experimental literature published between June 2011 and September 2016 was conducted using a modified PICOS (population, intervention, comparison, outcomes, and study type) framework. A total of 106 studies were included.

RESULTS

Behavioural data from 91 studies showed a broad cluster of deficits in the anticipatory control of movement, basic processes of motor learning, and cognitive control. Importantly, however, performance issues in DCD were often shown to be moderated by task type and difficulty. As well, we saw new evidence of compensatory processes and strategies in several studies. Neuroimaging data (15 studies, including electroencephalography) showed reduced cortical thickness in the right medial orbitofrontal cortex and altered brain activation patterns across functional networks involving prefrontal, parietal, and cerebellar regions in children with DCD than those in comparison groups. Data from diffusion-weighted magnetic resonance imaging suggested reduced white matter organization involving sensorimotor structures and altered structural connectivity across the whole brain network.

INTERPRETATION

Taken together, results support the hypothesis that children with DCD show differences in brain structure and function compared with typically developing children. Behaviourally, these differences may affect anticipatory planning and reduce automatization of movement skill, prompting greater reliance on slower feedback-based control and compensatory strategies. Implications for future research, theory development, and clinical practice are discussed.

Developmental coordination disorder: core sensori-motor deficits, neurobiology and etiology

Among developmental disorders, DCD is one of the least studied and less understood one (Bishop, 2010). This review summarizes the current understanding of developmental coordination disorder in neuropsychology with a focus mainly on high level sensorimotor impairments, its etiology and its neural bases. We summarize these core deficits in the framework of an influent motor control model (Blakemore et al., 2002). DCD has several environmental risk factors which probably interplay with genetic factors but those have not been sufficiently identified. High-level sensori-motor deficits are probably multifactorial in DCD and involve predictive coding deficits as well as weaknesses in perceptual and sensory integration. At the brain level, DCD is associated with impaired structure and functions within the motor network. Throughout the review we highlight exciting new findings as well as potential future lines of research to provide a more comprehensive understanding of this disorder.

Development of kinesthetic-motor and auditory-motor representations in school-aged children

In two experiments using a center-out task, we investigated kinesthetic-motor and auditory-motor integrations in 5- to 12-year-old children and young adults. In experiment 1, participants moved a pen on a digitizing tablet from a starting position to one of three targets (visuo-motor condition), and then to one of four targets without visual feedback of the movement. In both conditions, we found that with increasing age, the children moved faster and straighter, and became less variable in their feedforward control. Higher control demands for movements toward the contralateral side were reflected in longer movement times and decreased spatial accuracy across all age groups. When feedforward control relies predominantly on kinesthesia, 7- to 10-year-old children were more variable, indicating difficulties in switching between feedforward and feedback control efficiently during that age. An inverse age progression was found for directional endpoint error; larger errors increasing with age likely reflect stronger functional lateralization for the dominant hand. In experiment 2, the same visuo-motor condition was followed by an auditory-motor condition in which participants had to move to acoustic targets (either white band or one-third octave noise). Since in the latter directional cues come exclusively from transcallosally mediated interaural time differences, we hypothesized that auditory-motor representations would show age effects. The results did not show a clear age effect, suggesting that corpus callosum functionality is sufficient in children to allow them to form accurate auditory-motor maps already at a young age.

Development of interactions between sensorimotor representations in school-aged children

Reliable sensory-motor integration is a pre-requisite for optimal movement control; the functionality of this integration changes during development. Previous research has shown that motor performance of school-age children is characterized by higher variability, particularly under conditions where vision is not available, and movement planning and control is largely based on kinesthetic input. The purpose of the current study was to determine the characteristics of how kinesthetic-motor internal representations interact with visuo-motor representations during development. To this end, we induced a visuo-motor adaptation in 59 children, ranging from 5 to 12years of age, as well as in a group of adults, and measured initial directional error (IDE) and endpoint error (EPE) during a subsequent condition where visual feedback was not available, and participants had to rely on kinesthetic input. Our results show that older children (age range 9-12years) de-adapted significantly more than younger children (age range 5-8years) over the course of 36 trials in the absence of vision, suggesting that the kinesthetic-motor internal representation in the older children was utilized more efficiently to guide hand movements, and was comparable to the performance of the adults.

Differences in movement-related cortical activation patterns underlying motor performance in children with and without developmental coordination disorder

Behavioral deficits in visuomotor planning and control exhibited by children with developmental coordination disorder (DCD) have been extensively reported. Although these functional impairments are thought to result from "atypical brain development," very few studies to date have identified potential neurological mechanisms. To address this knowledge gap, electroencephalography (EEG) was recorded from 6- to 12-yr-old children with and without DCD (n = 14 and 20, respectively) during the performance of a visuomotor drawing task. With respect to motor performance, typically developing (TD) children exhibited age-related improvements in key aspects of motor planning and control. Although some children with DCD performed outside this TD landscape (i.e., age-related changes within the TD group), the group developmental trajectory of the children with DCD was similar to that of the TD children. Despite overall similarities in performance, engagement of cortical resources in the children with DCD was markedly different from that in their TD counterparts. While the patterns of activation are stable in TD children across the age range, the young children with DCD exhibited less engagement of motor cortical brain areas and the older children with DCD exhibited greater engagement of motor cortical brain areas than their TD peers. These results suggest that older children with DCD may employ a compensatory strategy in which increased engagement of relevant motor resources allows these children to perform comparably to their TD peers. Moreover, the magnitude of activation was related to several kinematic measures, particularly in children with DCD, suggesting that greater engagement in motor resources may underlie better behavioral performance.

Developmental delay of finger torque control in children with developmental coordination disorder

AIM

We examined whether the behavioral impairments in finger torque control evident in children with developmental coordination disorder (DCD) follow a delayed or different developmental trajectory compared with their typically developing peers.

METHOD

Children with DCD (n=36; 18 males, 18 females; mean age 9y 7mo, SD 1y 8mo) and 36 typically developing children (15 males, 21 females; mean age 9y 7mo, SD 2y), between 6 years 10 months and 12 years 7 months of age were recruited from schools in Porto Alegre, Brazil. Particpants completed finger torque control and maximum finger torque production tasks. The inclusion criterion for children with DCD was a Movement Assessment Battery for Children score below the fifth centile. Group means and cross-sectional age-related landscapes of the two groups were compared.

RESULTS

Children with DCD were more variable (p<0.001), less accurate (p=0.007), and less irregular (p<0.001), on average, in their finger torque control than their typically developing peers, despite producing nearly equivalent levels of maximum torque (p=0.49). Despite these mean differences, the cross-sectional age-related changes in torque control were similar in the two groups (all p>0.05).

INTERPRETATION

The developmental trajectory of finger torque control in children with DCD, compared with typically developing children, is delayed. This suggests the behavioral deficits in finger torque control in children with DCD persist as a function of age, rather than progressing or resolving.