Asperger syndrome in neurologic perspective

Motor and Visuomotor Skills of Children with Asperger's Disorder: Preliminary Findings

While motor clumsiness is frequently described as an associated feature of Asperger's Disorder, little research has examined specific motor skills and the relation among aspects of motor performance in this population. The present purpose was to present preliminary findings for three aspects of Asperger's: the presence and magnitude of gross motor and fine motor deficits, the presence and magnitude of visuomotor deficits, and the relation between motor functioning and visuomotor skills. 17 boys, 6 to 13 years old, with Asperger's were tested using standardized measures of gross, fine, and visuomotor skills. Statistically significant deficits were found for the sample's scores compared with values for the general population (using one-sample t tests), but none for fine motor vs gross motor skills (using a dependent sample t test). Significant positive correlations were found for gross motor skills with visuomotor skills (.73) and for fine motor skills with visuomotor skills (.71). Tentative suggestions for clinical assessment were proposed.

Neuropsychological investigation of motor impairments in autism

It is unclear how standardized neuropsychological measures of motor function relate to brain volumes of motor regions in autism spectrum disorder (ASD). An all-male sample composed of 59 ASD and 30 controls (ages 5-33 years) completed three measures of motor function: strength of grip (SOG), finger tapping test (FTT), and grooved pegboard test (GPT). Likewise, all participants underwent magnetic resonance imaging with region of interest (ROI) volumes obtained to include the following regions: motor cortex (precentral gyrus), somatosensory cortex (postcentral gyrus), thalamus, basal ganglia, cerebellum, and caudal middle frontal gyrus. These traditional neuropsychological measures of motor function are assumed to differ in motor complexity, with GPT requiring the most followed by FTT and SOG. Performance by ASD participants on the GPT and FTT differed significantly from that of controls, with the largest effect size differences observed on the more complex GPT task. Differences on the SOG task between the two groups were nonsignificant. Since more complex motor tasks tap more complex networks, poorer GPT performance by those with ASD may reflect less efficient motor networks. There was no gross pathology observed in classic motor areas of the brain in ASD, as ROI volumes did not differ, but FTT was negatively related to motor cortex volume in ASD. The results suggest a hierarchical motor disruption in ASD, with difficulties evident only in more complex tasks as well as a potential anomalous size-function relation in motor cortex in ASD.

Comparison of the Bender Gestalt-II and VMI-V in Samples of Typical Children and Children with High-Functioning Autism Spectrum Disorders

The visual-motor skills of 60 children with high-functioning autism spectrum disorders (HFASDs) and 46 typically developing children were assessed using the Bender Visual-Motor Gestalt Test— Second Edition (BG-II) and Beery-Buktenica Developmental Test of Visual-Motor Integration, Fifth Edition (VMI-V). Within-group comparisons yielded substantive mean differences between the BG-II Copy score and VMI-V composite,Visual Perception and Motor Coordination sections of the VMI-V, and Copy and Recall sections of the BG-II, in both samples. Between-groups differences were assessed in a subsample of 27 participants from each group matched on age, gender, ethnicity, and parent education. After statistically controlling for IQ, the HFASD group scored significantly lower than the typically developing group on the two scores from each test with greater motor involvement. Intratest and intertest correlations were similar across the two samples. Correlations between the BG-II Copy score and VMI-V composite were .55 for the HFASD and .48 for the typically developing sample.

[Asperger syndrome in childhood: review of four cases]

INTRODUCTION

Asperger syndrome is a pervasive developmental disorder included lately in the international classifications.

OBSERVATIONS

We report the observations of four children presenting this syndrome. For every patient, we collected antecedents and psychomotor development; we made neuropsychological assessment and video recording. Three patients underwent an EEG and one a cerebral MRI.

RESULTS

These patients were between ten- and sixteen-year old. The neuropsychological assessment showed a heterogeneous intellectual functioning with three times out of four a dissociation between high verbal level and low non-verbal level. Their language appeared sophisticated, apragmatic, their comprehension was inflexible. The mean age at diagnosis was ten years. They showed a sociability and autonomy improvement but they were conscious of their difference and suffered from it.

CONCLUSION

Our four cases allow to present Asperger syndrome, slightly known in France. Collaborative studies and genetic studies are necessary to improve the knowledge of this syndrome.

Child clinical/pediatric neuropsychology: some recent advances

The neuropsychological assets and deficits of several types of pediatric neurological disease, disorder, and dysfunction are described. These are examined from the perspective of the syndrome of nonverbal learning disabilities (NLD) and the "white matter model" designed to explain its complex manifestations. It is concluded that children with some of these diseases exhibit the NLD phenotype, whereas others do not. For the most part, the diseases in which the NLD phenotype is particularly evident are those wherein it has been demonstrated that perturbations of white matter (long myelinated fibers) are particularly prominent.

"Motor" impairment in Asperger syndrome: evidence for a deficit in proprioception

Motor impairment has frequently been described in Asperger syndrome (AS), a pervasive developmental disorder included in the Diagnostic and Statistical Manual of Mental Disorders, 4th Edition (DSM-IV). Previous research focusing on this motor dysfunction has yielded inconsistent results, and the "clumsiness" observed clinically remains poorly defined. To clarify further the issue of motor impairment, we compared a group of 10 children and young adults who met DSM-IV criteria for AS with a control group with no neurological impairment. Subjects were matched on age, sex, socioeconomic status, and Verbal IQ. A broad battery of motoric tests was administered. Subjects with AS were found to perform more poorly than controls on tests of apraxia, one-leg balance with eyes closed, tandem gait, and repetitive finger-thumb apposition. No significant differences were found on tests of finger tapping, grooved pegboard, trail making, or visual-motor integration. The pattern of impairments suggests that a proprioceptive deficit may underlie the incoordination observed in AS and that these individuals may be overreliant on visual input to maintain balance and position in space.

Occurrence of tics in Asperger's syndrome and autistic disorder

Asperger's syndrome is a condition in the autistic spectrum in which language development is normal. Patients with Asperger's syndrome frequently exhibit repetitive movements (stereotypies), and can have motor and phonic tics in addition to other behavioral abnormalities. We present 12 patients with autistic spectrum disorders who were referred to our Movement Disorders Clinic for evaluation of tics. Eight of the 12 had normal language development and therefore met criteria for Asperger's syndrome. All patients exhibited stereotypic movements; in addition, seven had tics and six of these met diagnostic criteria for Tourette syndrome. Of the six patients with clinical features of both Asperger's syndrome and Tourette syndrome, three had severe congenital sensory deficits. The autistic patients in our series were clinically heterogeneous and though tics were clearly present, other aberrant movements demonstrated by them were harder to classify. Our series confirms the wide range of clinical manifestations in Asperger's syndrome and autism, including tics and other features of Tourette syndrome. Furthermore, it suggests that sensory deprivation contributes to the development of adventitious movements in this population.

The screening and diagnosis of autistic spectrum disorders

The Child Neurology Society and American Academy of Neurology recently proposed to formulate Practice Parameters for the Diagnosis and Evaluation of Autism for their memberships. This endeavor was expanded to include representatives from nine professional organizations and four parent organizations, with liaisons from the National Institutes of Health. This document was written by this multidisciplinary Consensus Panel after systematic analysis of over 2,500 relevant scientific articles in the literature. The Panel concluded that appropriate diagnosis of autism requires a dual-level approach: (a) routine developmental surveillance, and (b) diagnosis and evaluation of autism. Specific detailed recommendations for each level have been established in this document, which are intended to improve the rate of early suspicion and diagnosis of, and therefore early intervention for, autism.