Anthropometric measures of Spanish children with autism spectrum disorder

We aimed to compare body mass index (BMI) and healthy eating index (HEI) in children with autism spectrum disorder (ASD, n = 105) and typically developing (TD, n = 495) children. They were aged 6–9 years, lived in Valencia (Spain) and came from similar cultural and socio-economic backgrounds. In this case–control study, the weight, height and BMI were measured for both groups. Three-day food records were used to assess dietary intake. Although the differences between children with ASD and TD children in raw BMI (p = 0.44), BMI z-score (p = 0.37), HEI (p = 0.43) and total energy intake (p = 0.86) were not significant, children with ASD and the boys subgroup were shorter (p = 0.01), but not the girls subgroup, compared to TD children of the same gender. Using the controls values as a reference, the BMI distribution in children with ASD became distorted, with values below the 5th percentile (11% vs. 4%, p = 0.03) and above the 95th percentile (8% vs. 5%, p = 0.04). The gender- and age-adjusted odds ratios for being underweight in the groups of all children and boys with ASD were 3.03 and 2.39, respectively, vs. TD children. Our data suggest that routine monitoring of children with ASD should include anthropometric measurements and assessment of their dietary habits.     

High risk for obesity in children with a subtype of developmental coordination disorder

The purpose of this study was to compare the prevalence of overweight and obesity in typically developing (TD) children, children with developmental coordination disorder (DCD) and balance problems (DCD-BP), and children with DCD without balance problems (DCD-NBP). Two thousand and fifty-seven children (1095 boys, 962 girls) ages 9–12 years were recruited from 18 elementary schools in Taiwan. The Movement Assessment Battery for Children was used to assess motor coordination ability. International cut-off points for body mass index were used to classify participants into the following groups: normal-weight, overweight or obese. Compared with TD children, children in the DCD-BP group were more than twice as likely to be obese (OR = 2.28; 95% CI = 1.41–3.68). DCD-BP children were also more likely to be obese compared to DCD-NBP children (OR = 1.79; 95% CI = 1.02–3.16). Boys in the DCD-BP group were more likely to be obese when compared to DCD-BP girls (OR = 3.12; 95% CI = 1.28–7.57). Similarly, DCD-NBP boys were more likely to be obese when compared to DCD-NBP girls (OR = 2.67; 95% CI = 1.21–5.89). Children with both DCD and BP were significantly more likely to be obese when compared to TD and DCD-NBP children. From an intervention perspective, the inclusion of regular physical activity, including activities that encourage development of both balance and energy expenditure, may be required to prevent obesity in this population.     

The effectiveness of a fundamental motor skill intervention in pre-schoolers with motor problems depends on gender but not environmental context

This study evaluated the effect of a 10-week fundamental motor skill programme in pre-schoolers with motor problems. Alongside the general effect of the intervention, we also explored possible gender differences and the role of the environmental context (living community, socio-economic status, and recreational space inside/outside the house). The intervention group (n = 47; 20 ♂ and 27 ♀) received twenty 60-min motor skill sessions (2 per week) in addition to the regular physical education curriculum for pre-schoolers; the control group (n = 46; 21 ♂ and 25 ♀) did not receive additional practice. General motor competence, and locomotor and object control subscales, were assessed before and after the intervention using the Test of Gross Motor Development 2nd edition (TGMD-2). Data regarding environmental factors were gathered through a questionnaire. A Group × Gender × Time ANOVA revealed that the intervention group benefited significantly from the intervention and scored better than the control group at the post-test for general motor competence and both sub-categories (locomotor and object control skill). Moreover, the intervention programme was found to be effective in helping 49% of the intervention group to achieve an average motor skill level, according to the TGMD-2 norms, while a further decline in motor competence was observed in the control group. Interestingly, the effect appeared to be gender-specific, since object control skill improved only in girls of the intervention group. Considering the environmental context, none of the above-mentioned factors was found to have an influence on the effectiveness of the intervention. The present study highlights the need for an early motor skill programme with a gender-specific approach in order to help low skilled boys and girls master a diverse set of motor skills.     

Household task participation of children and adolescents with cerebral palsy,Down syndrome and typical development

This cross-sectional study compared patterns of household task participation (e.g., performance, assistance and independence) of youth with cerebral palsy (CP), Down syndrome (DS) and typical development (TD). Parents of 75 children and adolescents were interviewed to report on their youths’ active engagement in daily self-care and family-care tasks, using the children helping out: responsibilities, expectations and supports (CHORES) questionnaire. Groups were equivalent in age (mean = 9.3 years; SD = 2.2 years), sex (male = 39; female = 36), respondent education, presence of maid, and number of siblings at home, but differed on child cognitive function and family socioeconomic status, with the DS and the CP groups scoring lower than the TD group but not different from each other. ANOVA revealed group differences on CHORES performance of self-care tasks (p = 0.004), on total participation score (p = 0.04) and on assistance scores (p < 0.02). Post hoc comparisons showed that TD group scored higher than CP and DS groups on performance and assistance in self-care tasks and total assistance; TD and CP groups were similar on total performance and assistance in family-care tasks. The groups also differed on independence indices; the TD index was greater than the CP and DS, and the CP index was greater than the DS. Parents from the three groups did not differ on ratings of importance regarding their children's household participation (p = 0.416). In spite of observed differences, children and adolescents with CP and DS are actively engaged in daily self-care and family-care tasks; their participation at home is not prevented by the presence of their disabilities.     

Language profiles in children with Down Syndrome and children with Language Impairment: Implications for early intervention

This study investigated early language profiles in two groups of children with developmental disability: children with Down Syndrome (DS, n = 13) and children with Language Impairment (LI, n = 16). Vocabulary and grammatical skills in the two groups were assessed and compared to language skills of typically developing (TD) children matched on size of either their receptive or expressive vocabulary (n = 58). The study aimed to establish if language development in these groups is delayed or fundamentally different than the TD groups, and if the group with DS showed a similar language profile to the group with LI. There is a clinical motivation to identify possible key risk characteristics that may distinguish children who are likely to have LI from the variation observed in TD children.Three clear findings emerged from the data. Firstly, both receptive and expressive vocabulary compositions did not significantly differ in the clinical groups (DS and LI) after being matched to the vocabulary size of TD children. This provides further support for the idea that word learning for the children in the clinical groups is delayed rather than deviant. Secondly, children with LI showed a significantly larger gap between expressive and receptive word knowledge, but children with DS showed a pattern comparable to TD children. Thirdly, children with LI who understood a similar number of words as the TD children still had significantly poorer grammatical skills, further underlining the dissociation between lexical and grammatical skills in children with LI. Grammatical skills of children with DS were commensurate with their lexical skills. The findings suggest that language intervention should be specifically tailored to etiology rather than focused on general communication strategies, particularly in children with LI.     

A longitudinal study on gross motor development in children with learning disorders

This longitudinal study examined the development of gross motor skills, and sex-differences therein, in 7- to 11-years-old children with learning disorders (LD) and compared the results with typically developing children to determine the performance level of children with LD.In children with LD (n = 56; 39 boys, 17 girls), gross motor skills were assessed with the Test of Gross Motor Development-2 and measured annually during a 3-year period. Motor scores of 253 typically developing children (125 boys, 112 girls) were collected for references values.The multilevel analyses showed that the ball skills of children with LD improved with age (p < .001), especially between 7 and 9 years, but the locomotor skills did not (p = .50). Boys had higher ball skill scores than girls (p = .002) and these differences were constant over time. Typically developing children outperformed the children with LD on the locomotor skills and ball skills at all ages, except the locomotor skills at age 7. Children with LD develop their ball skills later in the primary school-period compared to typically developing peers. However, 11 year-old children with LD had a lag in locomotor skills and ball skills of at least four and three years, respectively, compared to their peers.     

Psychological distress in children with developmental coordination disorder and attention-deficit hyperactivity disorder

This study explored whether or not a population-based sample of children with developmental coordination disorder (DCD), with and without comorbid attention deficit/hyperactivity disorder (ADHD), experienced higher levels of psychological distress than their peers. A two-stage procedure was used to identify 244 children: 68 with DCD only, 54 with ADHD only, 31 with comorbid DCD and ADHD, and 91 randomly selected typically developing (TD) children. Symptoms of depression and anxiety were measured by child and parent report. Child sex and caregiver ethnicity differed across groups, with a higher ratio of boys to girls in the ADHD only group and a slightly higher proportion of non-Caucasian caregivers in the TD group. After controlling for age, sex, and caregiver ethnicity, there was significant variation across groups in both anxiety (by parent report, F(3,235) = 8.9, p < 0.001; by child report, F(3,236) = 5.6, p = 0.001) and depression (parent report, F(3,236) = 23.7, p < 0.001; child report, F(3,238) = 9.9, p < 0.001). In general, children in all three disorder groups had significantly higher levels of symptoms than TD children, but most pairwise differences among those three groups were not significant. The one exception was the higher level of depressive symptoms noted by parent report in the ADHD/DCD group. In conclusion, children identified on the basis of motor coordination problems through a population-based screen showed significantly more symptoms of depression and anxiety than typically developing children. Children who have both DCD and ADHD are particularly at heightened risk of psychological distress.     

Object-related generativity in children with Down syndrome

Children with Down syndrome (DS) show challenges in some aspects of goal-directed behavior when compared to developmentally matched children (Daunhauer et al., 2014; Lee et al., 2011), particularly in the area of goal-directed action on objects (Fidler et al., 2005a, Fidler et al., 2005b). In this study, we examined one aspect of goal-directed action on objects, object-related generativity, in school-aged children with DS (n = 52), a developmentally matched group of children with intellectual disability, but not Down syndrome (DD; n = 21), and a group of chronologically younger, but developmentally matched typically developing children (TD; n = 34). We administered the Leiter-R, the Oral and Written Language Scales (OWLS), and an Object-Related Generativity Task, which involved 2 min of unstructured play with a variety of objects that have divergent usages. Children with DS generated significantly fewer instances of initiating actions on new objects than children in both comparison groups, were less likely to produce novel functional action on any object (new or familiar) than TD children, and they showed fewer instances of novel functional object engagement with new objects overall than TD children. Frequency of acts on new objects in DS was associated with Leiter-R Form Completion and Repeated Patterns Raw Scores and OWLS Listening Comprehension Raw Scores. These findings contribute to the growing knowledge base regarding goal-directed behavior and self-regulation in individuals with Down syndrome. Implications for education and intervention are discussed.     

Does somatosensory discrimination activate different brain areas in children with unilateral cerebral palsy compared to typically developing children? An fMRI study

Aside from motor impairment, many children with unilateral cerebral palsy (CP) experience altered tactile, proprioceptive, and kinesthetic awareness. Sensory deficits are addressed in rehabilitation programs, which include somatosensory discrimination exercises. In contrast to adult stroke patients, data on brain activation, occurring during somatosensory discrimination exercises, are lacking in CP children. Therefore, this study investigated brain activation with functional magnetic resonance imaging (fMRI) during passively guided somatosensory discrimination exercises in 18 typically developing children (TD) (age, M = 14 ± 1.92 years; 11 girls) and 16 CP children (age, M = 15 ± 2.54 years; 8 girls). The demographic variables between both groups were not statistically different. An fMRI compatible robot guided the right index finger and performed pairs of unfamiliar geometric shapes in the air, which were judged on their equality. The control condition comprised discrimination of music fragments. Both groups exhibited significant activation (FDR, p < .05) in frontoparietal, temporal, cerebellar areas, and insula, similar to studies in adults. The frontal areas encompassed ventral premotor areas, left postcentral gyrus, and precentral gyrus; additional supplementary motor area (SMA_proper) activation in TD; as well as dorsal premotor, and parietal operculum recruitment in CP. On uncorrected level, p < .001, TD children revealed more left frontal lobe, and right cerebellum activation, compared to CP children. Conversely, CP children activated the left dorsal cingulate gyrus to a greater extent than TD children. These data provide incentives to investigate the effect of somatosensory discrimination during rehabilitation in CP, on clinical outcome and brain plasticity.     

Physical fitness in children with Developmental Coordination Disorder: Measurement matters

Children with Developmental Coordination Disorder (DCD) experience considerable difficulties coordinating and controlling their body movements during functional motor tasks. Thus, it is not surprising that children with DCD do not perform well on tests of physical fitness. The aim of this study was to determine whether deficits in motor coordination influence the ability of children with DCD to perform adequately on physical fitness tests. A case–control study design was used to compare the performance of children with DCD (n = 70, 36 boys, mean age = 8y 1mo) and Typically Developing (TD) children (n = 70, 35 boys, mean age = 7y 9mo) on measures of isometric strength (hand-held dynamometry), functional strength, i.e. explosive power and muscular endurance (Functional Strength Measurement), aerobic capacity (20 m Shuttle Run Test) and anaerobic muscle capacity, i.e. muscle power (Muscle Power Sprint Test). Results show that children with DCD were able to generate similar isometric forces compared to TD children in isometric break tests, but were significantly weaker in three-point grip strength. Performance on functional strength items requiring more isolated explosive movement of the upper extremities, showed no significant difference between groups while items requiring muscle endurance (repetitions in 30 s) and items requiring whole body explosive movement were all significantly different. Aerobic capacity was lower for children with DCD whereas anaerobic performance during the sprint test was not. Our findings suggest that poor physical fitness performance in children with DCD may be partly due to poor timing and coordination of repetitive movements.     

Performance on Functional Strength Measurement and Muscle Power Sprint Test confirm poor anaerobic capacity in children with Developmental Coordination Disorder

BackgroundThere is little and conflicting information about anaerobic performance and functional strength in children with Developmental Coordination Disorder (DCD).AimsTo investigate anaerobic capacity and functional strength in children with a clinical diagnosis of DCD (clin-DCD) and if differences were larger in older (age 7–10 years) compared to younger children (age 4–6 years). Furthermore to determine the percentage of children with clin-DCD that scored <15th percentile on the norm-referenced Functional Strength Measurement.MethodA clin-DCD group (36 boys, 11 girls, mean age: 7y 1mo, SD = 2y 1mo) and a typically developing group (TD) (57 boys, 53 girls, mean age: 7y 5mo, SD = 1y 10mo) were compared on Muscle Power Sprint Test (MPST) and Functional Strength Measurement (FSM).ResultsChildren with clin-DCD performed poorer on the MPST and FSM, especially on the muscle endurance items of the FSM. The differences were larger in the older children compared to the younger on the cluster muscle endurance and the FSM total score. Over 50% of clin-DCD group scored <15th percentile on the FSM.InterpretationDifferences between children with clin-DCD and TD children are even more pronounced in the older children, especially when tested on items requiring fast repetitive movements.     

Physical fitness and overweight in Israeli children with and without developmental coordination disorder: Gender differences

Physical fitness and overweight among children has become paramount in the general population and more so in children with developmental coordination disorder (DCD). The purpose of the current study was to examine the association between physical fitness and overweight in a sample of Israeli children in comparison to typical children, and to examine gender differences. DCD was identified through total scores on the movement assessment battery for children 2 (MABC-2) equal to or less than the 16th percentile as well as parents’ report that the child's deficits in motor skills interfered with at least two daily life activities. The sample included a group of children with DCD (n = 22, M age = 8.70 [SD = 1.36], 16 boys [73%]) and a control group of typical children (n = 47, M age = 8.90 [SD = 1.52], 34 boys [72%]). Measures included the strength subtest of the Bruininks–Oseretsky test of motor proficiency (BOT-2), the six minutes’ walk test (6MWT) with heart rate measure, BMI and the percentage of body fat. Significant differences between DCD and typical children were found on all variables of physical fitness and weight. A two-way analysis of variance (ANOVA) analysis (group/gender) also revealed significant interactions for the percentage of body fat (F = 8.51, p < .005) and BMI (F = 4.50, p < .038) meaning that less fit children are more obese. The current study supports previous findings that children with DCD are less physically fit and more overweight compared to typically developing children. Moreover, in comparing between the genders, the girls in the study sample weighed more and had a significantly higher percentage of body fat than boys, it is essential to further our understanding of the relationships between obesity, physical fitness and gender among children with and without DCD.     

Understanding physical activity and motivations for children with Developmental Coordination Disorder: An investigation using the Theory of Planned Behavior

Developmental coordination disorder (DCD) is a neurodevelopmental condition, affecting approximately 5–6% of children. Previous research has consistently found children with DCD being less physically active compared to typically-developing (TD) children; however, the psychosocial factors associated with physical activity for children with DCD are poorly understood. The purpose of this study was to examine how theory-based physical activity cognitions impacts physical activity behaviors for children with and without DCD. Participants included a sample of boys (N = 61, M_age = 13.25 ± .46) with DCD (n = 19) and without DCD (n = 42), drawn from a larger prospective cohort study. A questionnaire with psychosocial measures was first administered, and accelerometers were used to assess their physical activity behavior over the subsequent week. Findings indicate that DCD was significantly associated with lower physical activity (F(1,58) = 6.51, p < .05), and poorer physical activity cognitions (F(4,56) Wilks Lambda = 2.78, p < .05). Meditational analyses found attitudes (B = .23, p < .05) and subjective norms (B = .31, p < .05) partially mediating the relationship between DCD and physical activity. Overall, this study further confirms that the activity deficit that exists among boys with DCD, and that the relationship is partially mediated through some physical activity cognitions. Interventions should target the perceived approval of influential people, and the personal evaluations of physical activity for boys with motoric difficulties. These findings further emphasizes the discrepancy in physical activity that exist between boys with DCD and TD boys, and highlight the need to better understand the psychological factors related to physical activity for children with DCD.     

Sleep patterns and behaviour in typically developing children and children with autism,Down syndrome,Prader-Willi syndrome and intellectual disability

Sleep problems have often been reported in children with intellectual disabilities (ID). How anomalies in 24-h sleep patterns relate to behaviour difficulties in children with different types of ID remains to be elucidated. The purpose of this study was to assess 24-h sleep and behaviour patterns in children with a variety disorders including autism (n = 34), Down syndrome (DS, n = 12), Prader-Willi syndrome (n = 12), and children with intellectual impairments due to unknown etiologies (n = 24). 33 typically developing (TD) children served as a control group. 24-h sleep and behavioural data were accumulated over a 14-day period using diary methodology. Group differences in daytime behaviour and sleep patterns were noted with children with DS being quieter, having higher levels of daytime sleepiness, and being better behaved than children with autism. Daytime napping was significantly more prevalent in children with PWS than children with autism and TD children. At bedtime children with autism were less likely to be sleepy, and were poorly behaved, which was reflected in a longer sleep latency and later time asleep. Poorer night-time sleep quality and reduced 24-h sleep time were also noted in the autism group. These findings are of clinical importance, as they indicate that different interventions may be required to treat sleep and behaviour problems in children with different developmental disabilities.     

Implicit and explicit motor learning: Application to children with Autism Spectrum Disorder (ASD)

Aims and objectivesThis study aims to determine whether children with Autism Spectrum Disorder (ASD) are capable of learning a motor skill both implicitly and explicitly.MethodsIn the present study, 30 boys with ASD, aged 7–11 with IQ average of 81.2, were compared with 32 typical IQ- and age-matched boys on their performance on a serial reaction time task (SRTT). Children were grouped by ASD and typical children and by implicit and explicit learning groups for the SRTT.ResultsImplicit motor learning occurred in both children with ASD (p = .02) and typical children (p = .01). There were no significant differences between groups (p = .39). However, explicit motor learning was only observed in typical children (p = .01) not children with ASD (p = .40). There was a significant difference between groups for explicit learning (p = .01).DiscussionThe results of our study showed that implicit motor learning is not affected in children with ASD. Implications for implicit and explicit learning are applied to the CO-OP approach of motor learning with children with ASD.     

Severity of depressive symptomatology and functional impairment in children and adolescents with temporal lobe epilepsy

ObjectiveDepression is a frequent psychiatric disorder in children with temporal lobe epilepsy (TLE). However, severity of depressive symptoms (DS) is frequently neglected in these patients. This study aimed to determine severity of DS and global functioning by using quantitative measures and to establish their correlation with patients’ demographics and clinical variables.Methods31 children (mean age of 11.8 ± 2.3 years) with TLE were assessed with K-SADS-PL for axis I DSM-IV diagnosis. Severity of DS was measured by Children Depression Rating Scale-Revised – CDRS-R. Global functional impairment was evaluated with Child Global Assessment Scale-CGAS.Results25 patients (56% boys; 12 ± 2.3 years) had current DS, moderate or severe in 84% according to CDRS-R T-Score. Severity of DS was not correlated with age (p = 0.377), gender (p = 0.132), seizure control (p = 0.936), age of onset (p = 0.731), duration of epilepsy (p = 0.602) and the presence of hippocampal sclerosis (p = 0.614). Patients had moderate to major functional impairment measured by CGAS (48.7 ± 8.8), being adolescents more impaired than children (p = 0.03). Impairment of global functioning was not associated with epilepsy variables (p > 0.05).ConclusionChildren with TLE had moderate to severe DS early in the course of their disease with a relevant impact on their global functional activities, especially considering adolescents. Epilepsy severity seems not to be correlated to the severity of DS, contradicting the idea of a cause–consequence relationship. More systematic research is needed to better understand the association of depressive disorders in children and adolescents with TLE.     

Impact of tactile function on upper limb motor function in children with Developmental Coordination Disorder

This study investigated the presence of, and relationship between tactile dysfunction and upper limb motor function in children with Developmental Coordination Disorder (DCD) compared to typical developing (TD) children. Participants were 36 children aged 6–12 years. Presence of DCD (n = 20) or TD (n = 16) was confirmed using the Movement Assessment Battery for Children, second edition. All children participated in a comprehensive assessment of tactile registration (Semmes Weinstein Monofilaments); tactile spatial perception (Single Point Localisation (SPL) and two-point discrimination (2PD)); haptic perception (Stereognosis); speed of simple everyday manual tasks (Jebsen–Taylor Test of Hand Function (JTTHF)); and handwriting speed and accuracy (Evaluation Tool of Children's Handwriting (ETCH)). Compared to TD children, children with DCD demonstrated poorer localisation of touch in the non-dominant hand (p = 0.04), slower speed of alphabet writing (p < 0.05) and less legible handwriting (p < 0.01), but no difference in speed of simple everyday manual tasks (JTTHF: p > 0.05). Regression analysis showed that spatial tactile perception (SPL) predicted handwriting legibility (ETCH: r = 0.11) and speed of functional tasks (JTTHF: r = 0.33). These results suggest that tactile function, specifically single point localisation, should be a primary tactile assessment employed to determine reasons for upper limb motor difficulties experienced by children with DCD.     

Sensorimotor function in preschool-aged children with expressive language disorder

AimThe aim of the study was to evaluate functional motor performance and haptic object recognition in 5-year-old children with mild expressive language disorder (ELD) in comparison with age- and gender-matched healthy children.MethodsThe subjects were classified by speech-language pathologist using The Reynell Developmental Language Scales III and Boehm Test of Basic Concepts: Preschool as children with mild ELD (n = 29, incl. 23 boys and 6 girls) and children with typical language development as controls (n = 29, incl. 23 boys and 6 girls). The children were examined for manual dexterity, ball skills, static and dynamic balance by Movement-ABC, haptic object recognition (HOR), hand-grip strength (HGS) and vertical jumping performance.ResultsChildren with mild ELD demonstrated significantly higher scores (i.e., inferior performance) in all subtests of M-ABC (all p values <0.05), in haptic object recognition (p < 0.01) and vertical jumping height (p < 0.05) compared to controls. However, no statistically significant differences (p > 0.05) emerged from HGS. Boys with mild ELD demonstrated higher results in impairment score (p < 0.001), ball skills (p < 0.01) and balance (p < 0.01) of M-ABC, as well as in HOR (p < 0.05). Girls with mild ELD showed higher impairment score (p < 0.05) with lower percentile (p < 0.05) in M-ABC, indicating inferior motor performance, and lower HGS for the non-dominant hand (p < 0.05). Seven out of 29 (24.1%) children with mild ELD had definite or borderline motor difficulties, while only one child in control group (3.4%) demonstrated borderline motor difficulties.ConclusionsChildren with mild expressive language disorder do not perform as well as controls in tests of functional motor skills, but their results in tests demanding maximal muscle force generation are in level with typically developing children. Boys and girls with mild ELD demonstrated higher impairment scores in M-ABC, indicating the need to follow their overall development more closely.     

Postural sway patterns in children with autism spectrum disorder compared with typically developing children

Postural control is a fundamental building block of each child's daily activities. The aim of this study was to compare patterns of postural sway in children with autism spectrum disorder (ASD) with typically developing children (TD). We recruited 21 schoolchildren diagnosed with ASD aged 9–14 and 30 TD pupils aged 8–15. Postural sway parameters in composite, anteroposterior and mediolateral axis were reported. Furthermore we examined the impact of age and characteristics of autism on postural sway. Children with ASD exhibited higher amount of sway in anteroposterior range (p < 0.001), mediolateral range (p = 0.002), root mean square (p = 0.001), mean velocity (p = 0.03), and sway area (p = 0.007) compared with their TD peers. Children with ASD showed higher instability in mediolateral than anteroposterior axis though TD children demonstrated higher sway scores in anteroposterior than mediolateral direction. The rate of autism symptom severity significantly affected the postural sway in children with ASD (p < 0.05). In conclusion, patterns of postural control seem to be different in children with ASD compared with TD counterparts. This could be partially due to clinical features were underlying in ASD.     

Variability of cognitive development in children with Down syndrome: Relevance of good reasons for using the cluster procedure

The main goal of this cross-sectional study was to demonstrate that, in addition to a main change during childhood, the cognitive development of children with Down syndrome (DS) is characterized by interindividual variability in their cognitive functioning. Eighty-eight French children with DS took part in this experiment. They were divided into six chronological age groups: 6 years (N = 9), 7 years (N = 19), 8 years (N = 18), 9 years (N = 19), 10 years (N = 14) and 11 years (N = 9). They were assessed by means of the Differential Scales of Intellectual Efficiency. This test, composed of six independent scales, measures verbal abilities and nonverbal reasoning abilities. Initial analyses of the verbal and nonverbal subtest scores indicated a main change in cognitive skills. We then used a clustering approach to identify four cognitive profiles that distinguished the children with DS independently of age and gender. The results confirm that there is a growth in the cognitive skills of DS children. They also suggest that the cognitive functioning of DS children is characterized by different individual profiles. Implications for more fine-tuned research and intervention efforts are discussed.