Stability of rhythmic finger movement in children with a developmental coordination disorder

Interlimb coordination and spatiotemporal variability during walking and running in children with developmental coordination disorder and typically developing children

BACKGROUND

A different interlimb coordination and higher variability in movement patterns is evident in children with Developmental Coordination Disorder (DCD). The impact of DCD on interlimb coordination during walking and running is unknown.

AIM

To assess interlimb coordination and spatiotemporal variability during overground walking and running in children with and without DCD.

METHODS

Children with DCD and typically developing children (TDC), from 8 to 12 years participated. Children were equipped with portable sensors. Participants walked and ran for 3 min in an oval-path at their comfortable pace. Interlimb coordination, expressed by the phase coordination index (PCI), and spatiotemporal variability (coefficient of variance (CoV)) were collected.

RESULTS

Twenty-one children with DCD and 23 TDC participated. During walking, PCI showed similar values in both groups, but a higher spatiotemporal variability was observed in children with DCD. During running, PCI was higher (reduced coordination) in children with DCD than TDC and a higher spatiotemporal variability was shown.

CONCLUSIONS AND IMPLICATIONS

Only during running, interlimb coordination of children with DCD was lower than TDC. During both walking and running tasks, spatiotemporal variability was higher in DCD. Current results implicate that difficulties in children with DCD is more prominent when motor coordination is more challenged.

WHAT THIS PAPER ADDS

This paper adds to the literature on coordination and gait pattern in children with Developmental Coordination Disorder (DCD) through a cross-sectional analysis of interlimb coordination and variability of spatiotemporal measures of overground walking and running. Overground walking and running were performed in a large oval-path allowing the assessment of coordination and gait patterns in an ecological valid set-up. Our results indicate that during a more demanding task, namely running, children with DCD display a less coordinated running pattern, expressed by a significantly higher phase coordination index, than typically developing peers. During walking, the interlimb coordination was similar between both groups. The current result is in accordance with the hybrid model of DCD that states that motor coordination difficulties in DCD are dpendent on the interaction of the task, individual and environment. This highlights the importance of implementing running assessments in children with DCD and the need for task-oriented running training in clinical practice The study also supports previous findings that children with DCD show a higher variability in their gait pattern of both walking and running, expressed by higher coefficient of variance of spatiotemporal measures, than typically developing peers. Further understanding in the normal development of interlimb coordination during walking and running from childhood into adulthood will enhance interpretations of the phase coordination index in children with and without 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.

Neurologically Motivated Coupling Functions in Models of Motor Coordination

We present an analysis of two Haken-Kelso-Bunz (HKB) oscillators coupled by a neurologically motivated function. We study the effect of time delay and weighted self-feedback and mutual feedback on the synchronization behavior of the model. We focus on identifying parameter regimes supporting experimentally observed decrease in oscillation amplitude and loss of anti-phase stability that has inspired the development of the HKB model. We show that a combination of cross-talk and nonlinearity in the coupling, along with physiologically relevant time delay, is able to quantitatively account for both drop in oscillation amplitude and loss of anti-phase stability in a frequency dependent manner. Furthermore, we demonstrate that the transition between discrete and rhythmic movements could be captured by this model. To this end, we carry out theoretical and numerical analysis of the emergence of in-phase and anti-phase oscillations.

A developmental and clinical perspective of rhythmic interpersonal coordination: From mimicry toward the interconnection of minds

Imitation plays a critical role in the development of intersubjectivity and serves as a prerequisite for understanding the emotions and intentions of others. In our review, we consider spontaneous motor imitation between children and their peers as a developmental process involving repetition and perspective-taking as well as flexibility and reciprocity. During childhood, this playful dynamic challenges developing visuospatial abilities and requires temporal coordination between partners. As such, we address synchrony as form of communication and social signal per se, that leads, from an experience of similarity, to the interconnection of minds. In this way, we argue that, from a developmental perspective, rhythmic interpersonal coordination through childhood imitative interactions serves as a precursor to higher- level social and cognitive abilities, such as theory of mind (TOM) and empathy. Finally, to clinically illustrate our idea, we focus on developmental coordination disorder (DCD), a condition characterized not only by learning difficulties, but also childhood deficits in motor imitation. We address the challenges faced by these children on an emotional and socio-interactional level through the perspective of their impairments in intra- and interpersonal synchrony.

Children with developmental coordination disorder (DCD) can adapt to perceptible and subliminal rhythm changes but are more variable

Children with DCD demonstrate impairments in bimanual finger tapping during self-paced tapping and tapping in synchrony to different frequencies. In this study, we investigated the ability of children with DCD to adapt motorically to perceptible or subliminal changes of the auditory stimuli without a change in frequency, and compared their performance to typically developing controls (TDC). Nineteen children with DCD between ages 6-11years (mean age±SD=114±21months) and 17 TDC (mean age±SD=113±21months) participated in this study. Auditory perceptual threshold was established. Children initially tapped bimanually to an antiphase beat and then to either a perceptible change in rhythm or to gradual subliminal changes in rhythm. Children with DCD were able to perceive changes in rhythm similar to TDC. They were also able to adapt to both perceptible and subliminal changes in rhythms similar to their age- and gender- matched TDC. However, these children were significantly more variable compared with TDC in all phasing conditions. The results suggest that the performance impairments in bilateral tapping are not a result of poor conscious or sub-conscious perception of the auditory cue. The increased motor variability may be associated with cerebellar dysfunction but further behavioral and neurophysiological studies are needed.

Developmental coordination disorders: state of art

In the literature, descriptions of children with motor coordination difficulties and clumsy movements have been discussed since the early 1900s. According to the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV), it is a marked impairment in the development of fine or global motor coordination, affecting 6% of school-age children. All these children are characterized for developmental coordination disorder (DCD) in motor learning and new motor skill acquisition, in contrast to adult apraxia which is a disorder in the execution of already learned movements. No consensus has been established about etiology of DCD. Intragroup approach through factor and cluster analysis highlights that motor impairment in DCD children varies both in severity and nature. Indeed, most studies have used screening measures of performance on some developmental milestones derived from global motor tests. A few studies have investigated different functions together with standardized assessments, such as neuromuscular tone and soft signs, qualitative and quantitative measures related to gross and fine motor coordination and the specific difficulties -academic, language, gnosic, visual motor/visual-perceptual, and attentional/executive- n order to allow a better identification of DCD subtypes with diagnostic criteria and to provide an understanding of the mechanisms and of the cerebral involvement.

Developmental changes in lateralized inhibition of symmetric movements in children with and without Developmental Coordination Disorder

The present study investigates developmental changes in selective inhibition of symmetric movements with a lateralized switching task from bimanual to unimanual tapping in typically developing (TD) children and with Developmental Coordination Disorder (DCD) from 7 to 10 years old. Twelve right-handed TD children and twelve gender-matched children with DCD and probable DCD produce a motor switching task in which they have (1) to synchronize with the beat of an auditory metronome to produce bimanual symmetrical tapping and (2) to selectively inhibit their left finger's tapping while continuing their right finger's tapping and conversely. We assess (1) the development of the capacity to inhibit the stopping finger (number of supplementary taps after the stopping instruction) and (2) the development of the capacity to maintain the continuing finger (changes in the mean tempo and its variability for the continuing finger's tapping) and (3) the evolution of performance through trials. Results indicate that (1) TD children present an age-related increase in the capacity to inhibit and to maintain the left finger's tapping, (2) DCD exhibits persistent difficulties to inhibit the left finger's tapping, and (3) both groups improve their capacity to inhibit the left finger's movements through trials. In conclusion, the lateralized switching task provides a simple and fine tool to reveal differences in selective inhibition of symmetric movements in TD children and children with DCD. More theoretically, the specific improvement in selective inhibition of the left finger suggests a progressive development of inter-hemispheric communication during typical development that is absent or delayed in children with DCD.

Neural underpinnings of impaired predictive motor timing in children with Developmental Coordination Disorder

A dysfunction in predictive motor timing is put forward to underlie DCD-related motor problems. Predictive timing allows for the pre-selection of motor programmes (except 'program' in computers) in order to decrease processing load and facilitate reactions. Using functional magnetic resonance imaging (fMRI), this study investigated the neural correlates of motor timing in DCD (n=17) and typically developing children (n=17). The task involved motor responses to sequences of visual stimuli with predictive or unpredictive interstimulus intervals (ISIs). DCD children responded with a smaller reaction time (RT) advantage to predictive ISIs compared to typically developing children. Typically developing children exhibited higher activation in the right dorsolateral prefrontal cortex (DLPFC) and right inferior frontal gyrus (IFG) for responses at unpredictive as opposed to predictive ISIs, whereas activations in DCD children were non-differentiable. Moreover, DCD children showed less activation than typically developing children in the right DLPFC, the left posterior cerebellum (crus I) and the right temporo-parietal junction (TPJ) for this contrast. Notably, activation in the right temporo-parietal junction (TPJ) positively correlated with RT as an indicator of processing load in both groups. These data indicate that motor performance in DCD children requires extra processing demands due to impaired predictive encoding.

Auditory and visual information do not affect self-paced bilateral finger tapping in children with DCD

Children with Developmental Coordination Disorder (DCD) are more variable in timing their fingers to an external cue. In this study, we investigated the intrinsic coordination properties of self-selected anti-phase finger tapping with and without vision and audition in children with and without DCD and compared their performance to that of adults. Ten children with DCD (Mean age=7.12±0.3 years), 10 age- and sex-matched typically developing (TD) children, and 10 adults participated in this study. Participants tapped their fingers in anti-phase at a self-selected speed under four different sensory conditions: (1) with vision and audition, (2) with vision but no audition, (3) with audition but no vision, and (4) without vision and audition. We assessed intertap interval (ITI), variability of ITI, mean relative phasing (RP) between the fingers and the variability in RP. Children with DCD adopted a similar mean frequency, but were less accurate and more variable than the other groups. The different sensory conditions did not affect performance in any of the groups. We conclude that visual and auditory feedback of tapping are not salient information sources for bilateral self-selected tapping and that children with DCD are intrinsically less accurate and more variable in their tapping frequency and coordination.

The complexity of childhood development: variability in perspective

The complexity of childhood development is exemplified in the variability of development that is seen across tasks and individuals. Furthermore, variability in performance is omnipresent within individuals across repetitions of a task and across individuals performing the same task. Previously, this variability was thought to reflect error of measurement or error of execution. On this account, variability reflects noise that should be filtered or averaged out of the data in order to reveal the "true" underlying characteristics of the performance. Although errors of measurement and execution indeed contribute to variability in movements, research in the last 2 decades has revealed characteristics of variability that are far more interesting than just noise. These characteristics can be deeply informative about underlying control processes and point to directions for clinical practice. This perspective article reviews different ways of characterizing variability, illustrates changes in variability as a result of development and learning, and discusses different theoretical perspectives on the role of variability that give clues about how to understand changes in variability and how to deal with variability in clinical settings.

Discrete bimanual co-ordination in children and young adolescents with hemiparetic cerebral palsy: Recent findings, implications and future research directions

Bimanual co-ordination is a field that has generated much research interest. It is clear that when hands move simultaneously there is a tendency for such movements to be synchronized. This phenomenon has also been observed in individuals with congenital brain damage, such as cerebral palsy. This paper provides an overview of past and current work in the area of bimanual co-ordination looking at the nature of the coupling and the underlying control of such movements. Work on 'non-disabled' individuals and unimanual reaching and grasping is included, but the main emphasis is bimanual co-ordination in children with hemiparetic cerebral palsy. The direction for future research is discussed and consideration given to the therapeutic implications of such work.

Auditory-motor coupling of bilateral finger tapping in children with and without DCD compared to adults

The ability to modulate bilateral finger tapping in time to different frequencies of an auditory beat was studied. Twenty children, 7 years of age, 10 with and 10 without developmental coordination disorder (DCD), and 10 adults tapped their left index and right middle fingers in an alternating pattern in time with an auditory signal for 15s (four trials each, randomly, at 0.8, 1.6, 2.4, 3.2 Hz per finger). Dominant and non-dominant finger data were collapsed since no differences emerged. All three groups were able to modulate their finger frequency across trials to closely approximate the signal frequency but children with DCD were unable to slow down to the lowest frequency. Children with DCD were more variable in tap accuracy (SD of relative phase) and between finger coordination than typically developing children who were respectively more variable than the adults. Children with DCD were unable to consistently synchronize their finger with the beat. Adults were tightly synchronized and often ahead of the beat while children without DCD tended to be behind the beat. Overall, these results indicated that children with DCD can only broadly match their finger movements to an auditory signal with variability and poor synchronicity as key features of their auditory-fine-motor control. Individual inspection of the data revealed that five children with DCD had difficulty matching the slowest frequencies and that these children also had higher variability and lower percentile MABC scores from the movement assessment battery for children (MABC) than other children with DCD. Three children with DCD were more variable only at higher frequencies and two performed like typically developing children.

Temporal variability in continuous versus discontinuous drawing for children with Developmental Coordination Disorder

Children with Developmental Coordination Disorder (DCD) are reported to have high temporal variability in tasks requiring precise timing. The current study examined whether this timing deficit was due to the cerebellar 'explicit timing' process in the discontinuous, but not the continuous movement. Ten children with DCD and 31 typically developing children performed continuous, discontinuous circle and line drawing tasks. Results showed that both children with DCD and their age-matched controls had higher temporal variability in the discontinuous than that in the continuous movements. Individual comparisons between each child with DCD and the performance of typically developing children revealed that 2 out of 10 children with DCD showed limited timing deficit in both types of discontinuous drawing (lines and circles). Additionally, three different children with DCD had timing problems with only discontinuous line drawing. Thus, the possibility of a compromised cerebellar function may exist in a subgroup of children with DCD. This work raises a critical issue with respect to the functional heterogeneity of this population and emphasizes the importance of an individualized analysis in this movement disorder.

Developmental sequences of two-handed catching: how do children with and without developmental coordination disorder differ?

The present study examined the movement patterns in children with developmental coordination disorder (DCD) and their age-matched controls (AMC) while catching two-handed. First, a cross-sectional study was conducted to investigate developmental characteristics within the three body component actions (arm, hand, and body) of two-handed catching hypothesized by Haywood and Getchell (2005). Data analyzed from 36 children (18 DCD, 18 AMC) aged 7-10 years who caught a ball 10 times, two-handed, showed that hypothesized sequences for the arm, hand, and body met the prelongitudinal screening criteria proposed by Roberton (1978), Langendorfer (1982), and Roberton, Williams, and Langendorfer (1980). In light of this, the second part of the study used these sequences to evaluate the movement patterns of 10 children with and 10 without DCD, aged 7-8 years. The data revealed that children with DCD displayed less advanced modal developmental sequence levels than AMC children with respect to the arm and body action components. (p <or= 0.01) Children with DCD also exhibited less advanced developmental profiles than the AMC children (p <or= 0.05), the group modal profiles being A2-H2-B2 and A3-H3-B3, respectively. These data also show that each child with DCD exhibited more developmental profiles over the 30 trials than the AMC children (p <or= 0.01) and that each DCD child's modal developmental profile was unstable (Roberton, 1977). Thus, over trials children with DCD link together different action patterns of the arm, hand, and body, suggesting that they have not yet developed a stable pattern of coordination to satisfy the task constraints.

Temporal organization of the brain: Neurocognitive mechanisms and clinical implications

The synchrony between the individual brain and its environment is maintained by a system of internal clocks that together reflect the temporal organization of the organism. Extending the theoretical work of Edelman and others, the temporal organization of the brain is posited as functioning through "re-entry" and "temporal tagging" and binds the wide range of possible times to a unified cognitive experience which is held in unison with the outside world. Dysfunction in this system is reflected in the temporal discord seen in cases of aging, sleep disorder, jet-lag, and shift-work, as well as in mental disorders and drug-induced changes in consciousness. The extent to which neuroendocrine structures contribute to the neurocognitive mechanisms which underlie consciousness has so far not been explored. Therefore, neuroendocrine mechanisms contributing to the temporal organization of the brain are reviewed. It is concluded that time-and its neuroendocrine correlate melatonin-is a binding principle for organizing conscious experience.

Developmental coordination disorder: a review of research on subtypes and comorbidities

The interest in Developmental Coordination Disorder (DCD) has grown considerably over the last decade. Nevertheless, its etiology and prognosis are still poorly understood. The idea is growing that DCD may not be a uniform disorder. This review summarizes research on DCD, with a particular focus on subtype and comorbidity studies. The main message of the paper is that, in order to understand the etiology and prognosis of DCD, we need to have a better understanding of its nature. This requires an awareness of the existence of subtypes and comorbidities. Current theories on comorbidity phenomena are discussed in terms of their possible merit for the development of the field. Particular attention is given to the Automatization Deficit Hypothesis, a theory based on research on dyslexia.

Clinical and research diagnostic criteria for developmental coordination disorder: a review and discussion

The aim of this review was to investigate the selection criteria used in the past in studies of children with developmental motor problems (excluding those suffering from neurological dysfunctions such as cerebral palsy, muscular dystrophy, etc.). We therefore conducted an extensive analysis of 176 publications. First, an overview of the main characteristics of these studies (terminology, population, type and purpose) and the selection criteria that are reported in these publications are presented. Following this, the DSM-IV selection criteria for developmental coordination disorder (DCD) are contrasted with the selection criteria reported in 41 publications that have used this terminology to classify the children. The results of this comparison show that the inclusion criteria are largely followed, albeit with little consistency concerning selection instruments and quantitative cut-offs, while adherence to the exclusion criteria is not common practice. Strengths and weaknesses of the DSM-IV criteria, complementary to the previous discussion by Henderson and Barnett in the HMS special issue on DCD in 1998 on this same topic, are discussed. The results of the review also show that many studies have used additional selection criteria related to the specific research questions of the study concerned. In the broader context of clinical practice as well as basic research, the latter result suggests the usefulness of a distinction between Clinical Diagnostic Criteria and Research Diagnostic Criteria. This distinction helps to develop a unifying view on the use of diagnostic criteria for research and clinical practice. We conclude with a number of recommendations concerning the selection criteria for children with DCD.

The efficacy of Le Bon Départ and Sensory Integration treatment for children with developmental coordination disorder: a randomized study with six single cases

OBJECTIVE

Evaluation of the efficacy of Le Bon Départ (LBD) treatment and Sensory Integration (SI) treatment on motor performance of children with developmental coordination disorder.

DESIGN

A single subject design with multiple baseline and alternating treatments. Order of treatment and length of phase were randomized. Measurements were blinded.

SETTING

Department of Occupational Therapy at the Academic Hospital Vrije Universiteit Amsterdam, The Netherlands.

SUBJECTS

Five boys and one girl with developmental coordination disorder (age: 6.0-8.1 years).

INTERVENTIONS

Baseline condition, Le Bon Départ treatment and Sensory Integration treatment.

MAIN OUTCOME MEASURES

The Movement ABC, Praxis Tests, a rhythm test and visual analogue scales. With the exception of the Praxis Tests, lower scores indicate better performance.

RESULTS

During both treatments, the performance on the Movement ABC (x = 7.21) and the scores on the visual analogue scales (x = 46.64) were significantly better than in the baseline (Movement ABC(baseline): x = 17.38; visual analogue scales(baseline): x = 68.18). After treatment 2, performance on the Praxis Tests and scores on the visual analogue scales were significantly better than after treatment 1 (Praxis Tests: 113.54 versus 104.68; visual analogue scales: 34.74 versus 58.54). All six children performed better on the Movement ABC during treatment as compared to the baseline. Le Bon Départ led to significant improvement on all dependent variables, Sensory Integration on the visual analogue scales only. The improvements after Le Bon Départ were larger than the improvements after Sensory Integration treatment. On the rhythm test this difference was significant: LBD led to an improvement of 43.01 points, while the improvement after SI was 17.59 points (p < 0.05).

CONCLUSION

Motor performance of children with developmental coordination disorder improved significantly on all dependent variables after the combination of treatments. Le Bon Départ led to more improvement than Sensory Integration. LBD appears to be a valuable treatment method for children with developmental coordination disorder.