Attention-deficit/hyperactivity disorder (ADHD) and developmental coordination disorder (DCD) co-occur in approximately 50% of cases. This study aimed to characterize the behavioral, cognitive, and ...neurobiological profiles of co-occurring ADHD and DCD diagnoses by mapping, synthesizing, and providing a critical appraisal of the existing literature. A systematic search was conducted across four databases (MEDLINE, PsycINFO, Embase, and Scopus) to identify studies comparing a coexisting ADHD+DCD diagnosis to ADHD and DCD alone. From 2353 screened articles, 15 behavioral and 10 neuroimaging studies were included. Collectively, these studies suggest that the comorbid ADHD+DCD presentation constitutes a more severe phenotype characterized by neurocognitive differences associated with both conditions. Despite sharing some common neural features, our findings support the separate etiology hypothesis indicating that neural network alterations in individuals with ADHD+DCD represent a unique neural pattern rather than a sum of ADHD and DCD characteristics. Considering the heterogeneity inherent to both ADHD and DCD, future studies should involve rigorous and comprehensive assessment procedures to delineate how different subtypes of each diagnosis relate to distinct performance characteristics.
•ADHD and DCD co-occur in approximately 50% of cases.•We examined the behavioral, cognitive, and neurobiological characteristics of coexisting ADHD and DCD diagnoses.•Results indicate separate etiologies for ADHD and DCD, with the comorbid presentation constituting a more severe phenotype.•Neural network alterations in ADHD+DCD represent a unique neural pattern rather than a sum of ADHD and DCD characteristics.•More research is needed to understand the factors contributing to high rates of comorbidity between ADHD and DCD.
Developmental coordination disorder (DCD) is a heterogeneous condition. Besides motor impairments, children with DCD often exhibit poor visual perceptual skills and executive functions. This study ...aimed to characterize the motor, perceptual, and cognitive profiles of children with DCD at the group level and in terms of subtypes. A total of 50 children with DCD and 31 typically developing (TD) peers (7–11 years old) underwent a comprehensive neuropsychological (15 tests) and motor (three subscales of the Movement Assessment Battery for Children-2) assessment. The percentage of children with DCD showing impairments in each measurement was first described. Hierarchical agglomerative and K-means iterative partitioning clustering analyses were then performed to distinguish the subtypes present among the complete sample of children (DCD and TD) in a data-driven way. Moderate to large percentages of children with DCD showed impaired executive functions (92%) and praxis (meaningless gestures and postures, 68%), as well as attentional (52%), visual perceptual (46%), and visuomotor (36%) skills. Clustering analyses identified five subtypes, four of them mainly consisting of children with DCD and one of TD children. These subtypes were characterized by: (i) generalized impairments (8 children with DCD), (ii) impaired manual dexterity, poor balance (static/dynamic), planning, and alertness (15 DCD and 1 TD child), (iii) impaired manual dexterity, cognitive inhibition, and poor visual perception (11 children with DCD), (iv) impaired manual dexterity and cognitive inhibition (15 DCD and 5 TD children), and (v) no impairment (25 TD and 1 child with DCD). Besides subtle differences, the motor and praxis measures did not enable to discriminate between the four subtypes of children with DCD. The subtypes were, however, characterized by distinct perceptual or cognitive impairments. These results highlight the importance of assessing exhaustively the perceptual and cognitive skills of children with DCD.
Children with Developmental Coordination Disorder (DCD-C) have motor coordination deficits which lead to difficulties in sports and play activities that require adaptations of the walking pattern. ...Sports and play often involve performing dual tasks, which affects performance in DCD-C more than in typically developing children (TD-C). So far, testing the impact of dual tasking on walking adaptability in DCD-C has received little scientific attention.
We tested the hypothesis that 6–12 year old DCD-C will show lower levels of walking adaptability than TD-C, and that due to problems with automatization this difference will increase when they are forced to divide their attention between tasks when a concurrent visuo-motor or cognitive task is added.
Twenty-six DCD-C and sixty-nine TD-C were included in this cross-sectional study. They performed a challenging walking adaptability (WA) task on a treadmill as a single, a visuo-motor dual and a cognitive dual task at a pace of 3.5 km/h. Repeated measures ANCOVAs were performed with condition (single/dual task) as within-subjects factor, group (TD/DCD) as between-subjects factor, and age as covariate.
DCD-C performed poorer on the WA task than TD-C. The group differences increased when a concurrent visuo-motor task was added, but not when adding a concurrent cognitive task. A significant effect of age was found with younger children performing worse on all tasks.
The results highlight the problems DCD-C have with walking adaptability and dual tasks, which capacities are essential for full participation in sports and play activities. Future research should investigate whether DCD-C may benefit from task-specific walking adaptability training.
•We studied walking adaptability (WA) and dual tasking in children with DCD.•A WA task on a treadmill was combined with a secondary visuo-motor or cognitive task.•Children with DCD performed poorer on all tasks than typically developing children.•The secondary visuo-motor task aggravated WA performance deficits in children with DCD.•Future research may investigate whether children with DCD benefit from WA training.
Most research on neurodevelopmental disorders has focused on their abnormalities. However, what remains intact may also be important. Increasing evidence suggests that declarative memory, a critical ...learning and memory system in the brain, remains largely functional in a number of neurodevelopmental disorders. Because declarative memory remains functional in these disorders, and because it can learn and retain numerous types of information, functions, and tasks, this system should be able to play compensatory roles for multiple types of impairments across the disorders. Here, we examine this hypothesis for specific language impairment, dyslexia, autism spectrum disorder, Tourette syndrome, and obsessive-compulsive disorder. We lay out specific predictions for the hypothesis and review existing behavioral, electrophysiological, and neuroimaging evidence. Overall, the evidence suggests that declarative memory indeed plays compensatory roles for a range of impairments across all five disorders. Finally, we discuss diagnostic, therapeutic and other implications.
Pedestrians are one of the most vulnerable groups at the roadside, furthermore, previous research has demonstrated perceptual-motor limitations in individuals with DCD which may put these individuals ...at even more at risk in the context of road crossing. However, it is unclear whether this is the lived experience of these individuals at the roadside. Furthermore, difficulties with road crossing and safety have been found in other neurodevelopmental disorders but the impact this might have on an individual with co-occurring difficulties is unknown. Therefore, we utilized a questionnaire to survey the lived experience of adults with DCD and parents of children with DCD with the specific objectives of describing behaviors exhibited by adults and children with DCD (the latter reported by parents) at the roadside and to determine the how these individuals perceive road crossing actions. For each of these we compared different co-occurrence groups. We also had one final objective which was not focused on road crossing but more on the general perception of accidents and unrealistic optimism. Individuals with co-occurrences which have previously been linked to unsafe crossing behaviors (i.e., ADHD, ASD, and LD) reported a greater regularity of dangerous looking behavior (forgetting to look, running without looking) and visibility (crossing between cars, crossing when you can't see), these adults and the parents of these children were seemingly aware of the risky nature of these behaviors. When asked "why" crossing ability might be different, perceptual and motor difficulties alongside heightened awareness of risk and lowered awareness of risk were all cited by participants. Unrealistic optimism was not an explanation for the risky behavior in adults with DCD and in fact, these adults demonstrated a clear understanding of the likelihood of accidents. The findings of this study suggest that road crossing is perceived to be more challenging for both children and adults with DCD and this needs to be taken into account when considering remediation for this group.
Motor differences are common in Autism Spectrum Disorder (ASD), but rarely evaluated against diagnostic criteria for Developmental Coordination Disorder (DCD). We aimed to determine whether motor ...problems in ASD represent the possible co-occurrence of DCD. We retrospectively reviewed standardized assessments and parent-reports to evaluate motor ability in 43 individuals with ASD against diagnostic criteria for DCD, and compared to 18 individuals with DCD. Over 97% of cases in the ASD group scored below the 16th percentile in motor ability, with most below the 5th percentile. Over 90% of cases in the ASD group met criteria for co-occurring DCD. Motor challenges are a clinically-significant problem in ASD; systematically assessing the prevalence of co-occurring ASD + DCD is necessary to optimize assessment and intervention.
Background
The prevalence of autism has been reported to have increased worldwide. A decrease over time in the number of autism symptoms required for a clinical autism diagnosis would partly help ...explain this increase. This study aimed to determine whether the symptom level of clinically diagnosed autism cases below age 13 had changed over time.
Methods
Parents of Swedish 9‐year old twins (n = 28,118) participated in a telephone survey, in which symptoms and dysfunction/suffering related to neurodevelopmental disorders including autism, but also attention‐deficit/hyperactivity disorder (ADHD), Developmental Coordination Disorder (DCD), and Learning Disabilities (LD) in their children were assessed over a 10‐year period. Survey data was merged with the National Patient Register containing clinically registered autism diagnoses (n = 271).
Results
In individuals who had been clinically diagnosed with autism before the age of 13, the symptom score for autism decreased on average 30% over more than a decade in birth cohorts 1992–2002. There was an average decrease of 50% in the autism symptom score from 2004 to 2014 in individuals who were diagnosed with autism at ages 7–12, but there was no decrease in those diagnosed at ages 0–6.
Conclusions
Over time, considerably fewer autism symptoms seemed to be required for a clinical diagnosis of autism, at least for those diagnosed after the preschool years. The findings add support for the notion that the observed increase in autism diagnoses is, at least partly, the by‐product of changes in clinical practice, and flag up the need for working in agreement with best practice guidelines.
Developmental coordination disorder (DCD) and its functional restrictions may persist into adulthood. Nevertheless, the knowledge about DCD in adulthood and its association with health related ...quality of life (HRQOL) is limited.
To explore how individuals with suspected DCD experience DCD impacts as children and as adults and how these experiences predict their HRQOL.
Participants were 200 healthy individuals aged 20−64 (mean 32.66 ± 11.51): 18 with suspected DCD and 182 with normal motor performance (according to the Adult Developmental Coordination Disorder/Dyspraxia, ADC, Checklist cut-off score). Participants completed a sociodemographic/health questionnaire, the ADC and the WHOQOL-BREF which measures physical, psychological, social and environmental HRQOL.
The group with suspected DCD had significantly lower HRQOL (except for the physical domain). In the general sample, current feelings about the individual’s performance predicted all HRQOL domains. Among the study group, HRQOL was predicted by current perception of performance and difficulties experienced as a child.
The negative effects of DCD during childhood and adulthood may reduce adults' HRQOL, mainly in the psycho-social and environmental domains. The detailed profile provided by the ADC with its functional context may assist in evaluating DCD in adults and in tailoring intervention for improving HRQOL.
Infants born extremely preterm are at high risk for early feeding difficulties, as well as poor neurodevelopmental outcomes in childhood. Feeding, a complex motor skill, may be predictive of later ...neuromotor outcomes.
To determine the relationship between feeding behaviours of extremely preterm-born infants (<28 weeks gestational age) at 4-months corrected age (CA) and neurodevelopmental outcomes at 4–5 years.
Retrospective cohort design with prospectively collected data.
Infants born extremely preterm from September 1999 – October 2013 n = 412, mean gestational age 25.4 (1.3) weeks; mean birth weight 771 (168) grams. Oral feeding was assessed at 4-months CA by an experienced occupational therapist; infants were classified as either having poor suck-swallow (‘feeding difficulties’) or no feeding difficulties.
Motor outcomes were assessed at 4–5 years using the Movement Assessment Battery for Children (MABC). Children were categorized as: (1) typical motor development (TMD; n = 214); (2) Developmental Coordination Disorder (DCD; n = 116); or (3) major neurodevelopmental disorder (MND; n = 82).
Feeding behaviour at 4-months CA predicted DCD (OR = 2.95, CI 1.13–7.68) and MND (OR = 3.67, CI 1.35–9.96) after controlling for confounders. Infants with feeding difficulties were more likely to be diagnosed with DCD (40 % of poor feeders) or MND (36 %) at 4–5 years, compared to infants without feeding issues.
Early feeding behaviours significantly predicted motor outcomes at 4–5 years. Infants born extremely preterm with early feeding difficulties should be identified as at high risk for poor motor outcomes later in childhood and screened for early diagnosis and intervention.
•Infant feeding difficulties are associated with major neurodevelopmental disorders.•Infant feeding problems may be an early marker for DCD in childhood.•Infants with poor feeding should be routinely screened for DCD and other disorders.
•First paper to consider specifically females with DCD.•There are age and gender differences in adults with DCD.•Females report more gross motor and non-motor difficulties, it is important to ...consider it for screening and intervention.
Developmental Coordination Disorder (DCD), also called Dyspraxia, is a common Neurodevelopmental Disorder (NDD) that affects motor coordination with a marked impact on both academic and day-to-day living activities. It is increasingly clear that NDDs such as Attention-Deficit/Hyperactivity Disorder and Autism Spectrum Disorder may present differently in males and females, resulting in underdiagnoses of women and girls. Aims: To consider age and gender differences in the presentation of at-risk and probable DCD. Methods and Procedures: A sample of 1,476 adults aged 16–60 years were surveyed online using the Adult DCD Checklist.
Women with at-risk (n = 1 8 6, 1 6. 6 %) or probable DCD (n = 6 4 3, 5 6. 6 %) reported significantly greater gross motor and non-motor difficulties and significantly greater impact on activities and participation, whereas men with at-risk (n = 58,16.3 %) or probable (n = 177,49.9 %), DCD reported significantly greater fine motor difficulties. Emerging adults (aged 16−25 years) with at-risk (n = 65,14.3 %) or probable (293,64.3 %) DCD reported significantly greater non-motor difficulty than adults (aged 26−60+ years) with at-risk (n = 179,17.5 %) or probable (n = 518, 50.8 %) DCD.
Both age and gender differences were found in the presentation of at-risk and probable DCD in adults. This may have implications for the development of future DCD assessment tools and for the training of front-line staff who may encounter individuals with DCD throughout their lives, including teachers, doctors and employers’ Human Resources and Occupational Health staff.
PDF
