Brief report: a reappraisal of clumsiness as a diagnostic feature of Asperger syndrome

Gait in children with infantile/atypical autism: Age-dependent decrease in gait variability and associations with motor skills

Gait and its associations with prewalking motor milestones, motor skills, and age were investigated in 32 children with infantile/atypical autism and 36 typically developing controls. Gait was assessed using GAITRite recordings of spatiotemporal and variability gait parameters. Parents reported their child's prewalking motor milestones. Motor skills were assessed using the Movement Assessment Battery for Children. Children with infantile/atypical autism showed higher gait variability than controls, indicating a less regular walking pattern. In children with infantile/atypical autism gait variability was negatively associated with motor skills, but there was no such association with prewalking motor milestones. The higher gait variability in children with infantile/atypical autism showed an age-dependent decrease, suggesting that their gait regularity converges toward that of typically developing children.

Comparison of ICD-10 and Gillberg’s Criteria for Asperger Syndrome

In this study, algorithms designed for the Diagnostic Interview for Social and Communication Disorders (DISCO) were used to compare the ICD-10 criteria for Asperger syndrome with those suggested by Gillberg. Two hundred children and adults were studied, all of whom met the ICD-10 criteria for childhood autism or atypical autism. Only three (1 percent) met criteria for ICD-10 Asperger syndrome. In contrast, 91 (45 percent) met criteria for Asperger syndrome defined by Gillberg, which more closely resemble Asperger’s own descriptions. Results showed that the discrepancy in diagnosis was due to the ICD-10 requirement for ‘normal’ development of cognitive skills, language, curiosity and self-help skills. When comparisons were based on Gillberg’s criteria only, results showed the participants diagnosed as having Asperger syndrome differed significantly from the rest on all but two of Gillberg’s criteria. However, all of these criteria could be found in some of those not diagnosed as having Asperger syndrome. The results emphasize the differences between the two diagnostic systems. They also question the value of defining a separate subgroup and suggest that a dimensional view of the autistic spectrum is more appropriate than a categorical approach.

A review of embodiment in autism spectrum disorders

In classical approaches to cognition, sensory, motor, and emotional experiences are stripped of domain-specific perceptual and sensorimotor information, and represented in a relatively abstract form. In contrast, the embodied cognition framework suggests that our representations retain the initial imprint of the manner in which information was acquired. In this paper, we argue that individuals with autism spectrum disorders (ASD) display impairments in the temporal coordination of motor and conceptual information (as shown in gesture research) and striking deficits in the interpersonal mimicry of motor behaviors (as shown in yawning research) - findings we believe are consistent with an embodied account of ASD that includes, but goes beyond, social experiences and is driven in part by significant but subtle motor deficits. In this paper, we review the research examining an embodied cognition account of ASD, and discuss its implications.

Gross motor performance and self-perceived motor competence in children with emotional, behavioural, and pervasive developmental disorders: a review

AIMS

Motor performance and self-perceived motor competence have a great impact on the psychosocial development of children in general. In this review, empirical studies of gross motor performance and self-perception of motor competence in children with emotional (depression and anxiety), behavioural, and pervasive developmental disorders are scrutinized, with the objective of identifying specific motor characteristics that may be relevant to clinical practice.

METHOD

A systematic search of studies published between 1997 and 2007 was performed using nine search engines.

RESULTS

Children in all three categories (emotional, behavioural, and pervasive developmental disorders) exhibit poor gross motor performance and problematic self-perception of motor competence, with certain indications of disorder-specific characteristics. In particular, children with emotional disorders have balance problems and self-perceived motor incompetence; children with behavioural disorders show poor ball skills and tend to overestimate their motor performance; children with pervasive developmental disorders demonstrate poor gross motor performance and self-perceived motor incompetence. As a result, children with developmental and emotional disorders are restricted in participating in games and play, which may lead to inactive lifestyles and further disruption of their psychosocial and physical development.

INTERPRETATION

Motor problems need more, to some extent disorder-specific, attention in clinical practice than has been provided to date.

Impairment in movement skills of children with autistic spectrum disorders

AIM

We undertook this study to explore the degree of impairment in movement skills in children with autistic spectrum disorders (ASD) and a wide IQ range.

METHOD

Movement skills were measured using the Movement Assessment Battery for Children (M-ABC) in a large, well defined, population-derived group of children (n=101: 89 males,12 females; mean age 11y 4mo, SD 10mo; range 10y-14y 3mo) with childhood autism and broader ASD and a wide range of IQ scores. Additionally, we tested whether a parent-completed questionnaire, the Developmental Coordination Disorder Questionnaire (DCDQ), was useful in identifying children who met criteria for movement impairments after assessment (n=97 with complete M-ABCs and DCDQs).

RESULTS

Of the children with ASD, 79% had definite movement impairments on the M-ABC; a further 10% had borderline problems. Children with childhood autism were more impaired than children with broader ASD, and children with an IQ less than 70 were more impaired than those with IQ more than 70. This is consistent with the view that movement impairments may arise from a more severe neurological impairment that also contributes to intellectual disability and more severe autism. Movement impairment was not associated with everyday adaptive behaviour once the effect of IQ was controlled for. The DCDQ performed moderately well as a screen for possible motor difficulties.

INTERPRETATION

Movement impairments are common in children with ASD. Systematic assessment of movement abilities should be considered a routine investigation.

WISC-IV and WIAT-II Profiles in Children With High-Functioning Autism

Children with high-functioning autism earned above normal scores on the Wechsler Intelligence Scale for Children-Fourth Edition (WISC-IV) Perceptual Reasoning and Verbal Comprehension Indexes and below normal scores on the Working Memory and Processing Speed Indexes and Wechsler Individual Achievement Test-Second Edition (WIAT-II) Written Expression. Full Scale IQ (FSIQ) and reading and math scores were similar to the norm. Profiles were consistent with previous WISC-III research, except that the new WISC-IV motor-free visual reasoning subtests (Matrix Reasoning and Picture Concepts) were the highest of the nonverbal subtests. The WISC-IV may be an improvement over the WISC-III for children with high-functioning autism because it captures their visual reasoning strength, while identifying their attention, graphomotor, and processing speed weaknesses. FSIQ was the best single predictor of academic achievement.

An examination of movement kinematics in young people with high-functioning autism and Asperger's disorder: further evidence for a motor planning deficit

This paper examines upper-body movement kinematics in individuals with high-functioning autism (HFA) and Asperger's disorder (AD). In general, the results indicate that HFA is more consistently associated with impaired motoric preparation/initiation than AD. The data further suggest that this quantitative difference in motor impairment is not necessarily underpinned by greater executive dysfunction vulnerability in autism relative to AD. Quantitative motoric dissociation between autism and AD may have down-stream effects on later stages of movement resulting in qualitative differences between these disorder groups, e.g. "motor clumsiness" in AD versus "abnormal posturing" in autism. It will be important for future research to map the developmental trajectory of motor abnormalities in these disorder groups.

Motor signs distinguish children with high functioning autism and Asperger's syndrome from controls

While many studies of motor control in autism have focused on specific motor signs, there has been a lack of research examining the complete range of subtle neuromotor signs. This study compared performance on a neurologic examination standardized for children (PANESS, Physical and Neurological Exam for Subtle Signs, Denckla [1974 Developmental Medicine and Child Neurology, 16(6), 729-741]) between a group of 40 boys aged 6-17 with autism and average range IQs and a group of 55 typically developing boys. The Autism group was shown to have significant impairment on several measures of motor control compared to the Control group. Regression analyses revealed that a model including four PANESS variables offered a high level of discrimination in distinguishing boys with high-functioning autism from controls.

Fine motor skills in South African children with symptoms of ADHD: influence of subtype, gender, age, and hand dominance

BACKGROUND

Motor problems, often characterised as clumsiness or poor motor coordination, have been associated with ADHD in addition to the main symptom groups of inattention, impulsiveness, and overactivity. The problems addressed in this study were: (1) Are motor problems associated with ADHD symptoms, also in African cultures? (2) Are there differences in motor skills among the subtypes with ADHD symptoms? (3) Are there gender differences? (4) Is there an effect of age? (5) Are there differences in performance between the dominant and non-dominant hand?

METHOD

A total of 528 children (264 classified as having symptoms of ADHD and 264 matched comparisons) of both genders and from seven different South African ethnic groups participated in the study. They were assessed with three simple, easy to administer instruments which measure various functions of motor speed and eye-hand coordination: The Grooved Pegboard, the Maze Coordination Task, and the Finger Tapping Test. The results were analysed as a function of subtype, gender, age, and hand dominance.

RESULTS

The findings indicate that children with symptoms of ADHD performed significantly poorer on the Grooved Pegboard and Motor Coordination Task, but not on the Finger Tapping Test than their comparisons without ADHD symptoms. The impairment was most severe for the subtype with symptoms of ADHD-C (combined) and less severe for the subtypes with symptoms of ADHD-PI (predominantly inattentive) and ADHD-HI (predominantly hyperactive/impulsive). With few exceptions, both genders were equally affected while there were only slight differences in performance between the dominant and non-dominant hand. The deficiencies in motor control were mainly confined to the younger age group (6-9 yr).

CONCLUSION

An association between the symptoms of ADHD and motor problems was demonstrated in terms of accuracy and speed in fairly complex tasks, but not in simple motor tests of speed. This deficiency is found mainly in the children with ADHD-C symptoms, but also to a lesser degree in the children with symptoms of ADHD-PI and ADHD-HI.

The quality of life of young men with Asperger syndrome: a brief report

Factors influencing quality of life for persons with Asperger syndrome are not yet understood. Men, ages 18 to 21, completed the World Health Organization Quality Of Life measure, the Perceived Support Network Inventory, and a semi-structured interview. Asperger syndrome affects quality of life beyond the obvious social impact. The 12 men with Asperger syndrome reported a significantly lower social and physical quality of life than did the 13 men in the control group. Education, living arrangements, and number of friends were remarkably similar between groups. Those with Asperger syndrome had less positive employment experiences and showed more preference for solitary activities. Interventions need to be based on a holistic model.

Annotation: The similarities and differences between autistic disorder and Asperger's disorder: a review of the empirical evidence

BACKGROUND

The ongoing controversy over the distinction between autistic disorder and Asperger's disorder is important to resolve because of the implications regarding an understanding of the aetiology and prognosis, and the diagnostic and clinical practices relating to these conditions. This paper provides a critical evaluation of current published research evidence.

METHOD

Databases, such as PsychINFO and Medline, as well as book chapters, reference lists from relevant articles, and recent editions of key journals were searched for all relevant studies (until 2002) which incorporated participants diagnosed with high-functioning autism and Asperger's disorder using either cluster analysis or comparative approaches to examine similarities and differences between these groups. Keywords used in the searches included autistic disorder, Asperger's disorder, autism, high-functioning autism, and pervasive developmental disorder.

RESULTS

On the basis of the available evidence, there seem to be few qualitative differences between autistic disorder and Asperger's disorder.

CONCLUSION

There is currently insufficient evidence to establish the validity of Asperger's disorder as a syndrome distinct from high-functioning autism. The findings are consistent with the view that these disorders belong on an autism spectrum.

Analysis of WISC-III, Stanford-Binet:IV, and academic achievement test scores in children with autism

Nonverbal IQs were greater than verbal IQs for young children (3-7 years of age) on the Stanford-Binet:IV (n = 53). However, WISC-III verbal and nonverbal IQs were similar for older children, 6-15 years of age (n = 63). Stanford-Binet:IV profiles were generally consistent for the low-IQ (< 80) and high-IQ (> or = 80) groups, with high scores on visual matching tests (Bead Memory and Quantitative Reasoning). The low- and high-WISC-III IQ groups both performed well relative to IQ on tests of lexical knowledge (Similarities, Information, and Vocabulary), but not on language comprehension and social reasoning (Comprehension). The low-IQ group did best on visuo-motor subtests (Object Assembly and Block Design), but the high-IQ group did not. The high-IQ group had significantly low scores on the Digit Span, Arithmetic, Coding, VMI, and WIAT Written Expression tests, suggesting attention and writing weaknesses.

Ability profiles in children with autism: influence of age and IQ

To understand the effect of IQ and age on ability in children with autism, psychological data were analyzed for 164 3- to 15-year-olds with autism (IQs 14-143). As age increased, so did IQ, which probably reflects both an actual increase in IQ over time and the likelihood that brighter children are diagnosed later. Early in life, 67 percent had normal motor and delayed speech milestones. Verbal IQ continued to lag behind non-verbal IQ during the preschool years. By school age, the gap between verbal and non-verbal IQs had closed. Visual reasoning exceeded graphomotor scores for all children, and surpassed IQ for most. Graphomotor scores were significantly below IQ for both high-IQ groups. For school-age children with low IQs, math, spelling, and writing scores were consistent with IQ and reading was above IQ. School-age children with high IQs had average reading, math, and spelling scores and a weakness in writing.

Outcome in high-functioning adults with autism with and without early language delays: implications for the differentiation between autism and Asperger syndrome

The question of whether Asperger syndrome and high-functioning autism should be considered as the same or different conditions has been a source of debate and controversy over recent years. In the present study, 34 adults with autism who had shown early delays in language were compared with 42 individuals who were reported to have had no such delays, either in their use of words or phrases. All participants were at least 18 years of age, had a nonverbal IQ of 70 or above and met ADI-R criteria for age of onset, communication and social impairments, and stereotyped behaviors. Those in the language delay group were diagnosed as having high-functioning autism. The remainder were designated as having Asperger syndrome. The groups were matched for age, nonverbal IQ and gender. No significant differences were found between the groups either in their total ADI-R algorithm scores, or in their algorithm scores on individual domains. Social outcome ratings and ADI-R scores based on current functioning also failed to differentiate between the groups. Scores on tests of language comprehension and expression were also similar, but in both groups language abilities were well below chronological age level. The implications of these results with respect to the differences between Asperger syndrome and high-functioning autism are discussed. The poor performance on language tests also challenges the assumption that early language development in Asperger syndrome is essentially normal.

A clinical and neurobehavioural review of high-functioning autism and Asperger's disorder

OBJECTIVE

To compare, contrast and review clinical and neuropsychological studies of high-functioning autism and Asperger's disorder.

METHOD

This paper reviews past and contemporary conceptualizations of autism and Asperger's disorder, together with epidemiological information, genetic and neurobehavioural findings. This paper focuses on neurobehavioural studies, in particular, executive functioning, lateralization, visual-perceptual and motor processing, which have provided an important source of information about the potential neurobiological dissociation that may exist between autism and Asperger's disorder.

RESULTS

The clinical profiles of autism and Asperger's disorder contain a mixture of psychiatric and neurological symptoms: for example, movement abnormalities (i.e. stereotyped behaviours, hand flapping, toe walking, whole-body movements), atypical processing of parts and wholes, verbal and non-verbal deficits, ritualistic/compulsive behaviour, disturbances in reciprocal social interaction and associated depression and anxiety. The considerable clinical overlap between autism and Asperger's disorder has led many to question whether Asperger's disorder is merely a mild form of autism, or whether it should be considered as a separate clinical entity.

CONCLUSION

In light of the growing body of epidemiological information, genetic, and neurobehavioural evidence that distinguishes autism from Asperger's disorder, it is premature to rule out the possibility that these disorders may be clinically, and possibly neurobiologically separate.

Asperger syndrome: tests of right hemisphere functioning and interhemispheric communication

The primary aim of this investigation was to assess to what extent Rourke's (1989, 1995) nonverbal learning disabilities syndrome (NLD) model resembles the pattern of assets and deficits seen in people with Asperger syndrome (AS). NLD can be characterized by a cluster of deficits primarily affecting nonverbal aspects of functioning, in the presence of proficiency in single word reading and a superior verbal memory. The neurological underpinnings of this syndrome may be dysfunction of white matter affecting right hemisphere functioning and interhemispheric communication. To explore this hypothesis, eight participants with AS (ages 10 to 41 years) were assessed in the following areas: the pragmatics of language and communication, verbal and visual memory, visual-spatial abilities, and bimanual motor skills. Results confirmed the close similarity in the neuropsychologic profiles of NLD and AS.

The severity and nature of motor impairment in Asperger's syndrome: a comparison with specific developmental disorder of motor function

BACKGROUND

The aims of this study were to measure objectively the extent and severity of motor impairment in children with Asperger's syndrome and to determine whether the motor difficulties experienced by such children differed in any way from those classified as having a Specific Developmental Disorder of Motor Function (SDD-MF). Criteria derived from ICD 10-R were used to identify 11 children with Asperger's syndrome and a matched group of 9 children with a Specific Developmental Disorder of Motor Function. Children in both groups were required to have a verbal IQ of 80 or greater on the WISC IIIR.

METHOD

The Autism Diagnostic Interview (Revised; Lord, Rutter, & LeCouteur, 1994) was used to identify features of AS in the first group and to exclude them in the latter. The Movement Assessment Battery for Children (Henderson & Sugden, 1992) provided a standardised test of motor impairment. A Gesture Test based on that by Cermak, Coster, and Drake (1980) was used to assess the child's ability to mime the use of familiar tools and to imitate meaningless sequences of movements.

RESULTS

All the children with Asperger's syndrome turned out to meet our criterion for a diagnosis of motor impairment, five of the six most severely motor impaired children in the whole study being from this group. Performance of the Asperger group was also slightly poorer on the Gesture Test. The profile of performance on each test was examined in detail but no evidence of group differences in the pattern of impairment was found.

CONCLUSIONS

This study is consistent with others suggesting a high prevalence of clumsiness in Asperger's syndrome. Our findings also attest to the widespread prevalence of motor impairment in developmental disorders and the problems such co-morbidity poses for attempts to posit discrete and functionally coherent impairments underlying distinct syndromes.

Does DSM-IV Asperger's disorder exist?

DSM-IV criteria for autistic and Asperger's disorders were applied to 157 children with clinical diagnoses of autism or Asperger's disorder. All children met the DSM-IV criteria for autistic disorder and none met criteria for Asperger's disorder, including those with normal intelligence and absence of early speech delay. The reason for this was that all children had social impairment and restricted and repetitive behavior and interests (required DSM-IV symptoms for both autistic and Asperger's disorders) and all had a DSM-IV communication impairment (which then qualified them for a diagnosis of autistic disorder and not Asperger's disorder). Communication problems exhibited by all children were impaired conversational speech or repetitive, stereotyped, or idiosyncratic speech (or both), which are DSM-IV criteria for autism. These findings are consistent with those of 5 other studies and indicate that a DSM-IV diagnosis of Asperger's disorder is unlikely or impossible.

Non-significance of early speech delay in children with autism and normal intelligence and implications for DSM-IV Asperger's disorder

According to the DSM-IV, children with Asperger's disorder do not have significant cognitive or speech delays, whereas children with autistic disorder may or may not. In our study, children with normal intelligence who had clinical diagnoses of autism or Asperger syndrome were divided into two groups: those with and without a significant speech delay. The purpose was to determine if clinically meaningful differences existed between the two groups that would support absence of speech delay as a DSM-IV criterion for Asperger's disorder. No significant differences were found between the 23 children with a speech delay and the 24 children without a speech delay on any of the 71 variables analyzed, including autistic symptoms and expressive language. Results suggest that early speech delay may be irrelevant to later functioning in children who have normal intelligence and clinical diagnoses of autism or Asperger syndrome and that speech delay as a DSM-IV distinction between Asperger's disorder and autism may not be justified.

Movement preparation in high-functioning autism and Asperger disorder: a serial choice reaction time task involving motor reprogramming

Autism and Asperger disorder have long been associated with movement abnormalities, although the neurobehavioural details of these abnormalities remain poorly defined. Clumsiness has traditionally been associated with Asperger disorder but not autism, although this is controversial. Others have suggested that both groups demonstrate a similar global motor delay. In this study we aimed to determine whether movement preparation or movement execution was atypical in these disorders and to describe any differences between autism and Asperger disorder. A simple motor reprogramming task was employed. The results indicated that individuals with autism and Asperger disorder have atypical movement preparation with an intact ability to execute movement. An atypical deficit in motor preparation was found in Asperger disorder, whereas movement preparation was characterized by a "lack of anticipation" in autism. The differences in movement preparation profiles in these disorders were suggested to reflect differential involvement of the fronto-striatal region, in particular the supplementary motor area and anterior cingulate.

Interventions to facilitate auditory, visual, and motor integration in autism: a review of the evidence

Evidence is reviewed on the prevalence of sensory and motor abnormalities in autism and the effectiveness of three interventions designed to address such abnormalities--sensory integration therapy, traditional occupational therapy, and auditory integration training. Although sensory processing and motor abnormalities are neither universal nor specific to autism, the prevalence of such abnormalities in autism is relatively high. There is, however, little controlled research on the effectiveness of interventions designed to address these abnormalities. Four objective outcome studies of sensory integration therapy were identified. These were of such small scale that no firm conclusions regarding efficacy could be made. No empirical studies of traditional occupational therapy in autism were found. Five studies of auditory integration training were found. Results of these studies provided no, or at best equivocal, support for the use of auditory integration training in autism.

The external validity of Asperger disorder: lack of evidence from the domain of neuropsychology

The present study compared individuals with high-functioning autism (HFA) and Asperger disorder (AD) in intellectual, motor, visuospatial, and executive function domains. Participants with AD demonstrated significantly higher Verbal and Full Scale IQ scores, significantly larger Verbal-Performance IQ discrepancies, and significantly better visual-perceptual skills than those with HFA. Once the superior intellectual abilities of the AD group were controlled (both statistically through analysis of covariance and by examining IQ-matched subgroups of HFA and AD participants), no significant group differences in motor, visuospatial, or executive functions were evident, save a marginally significant trend toward poorer fine motor performance in the AD group. This suggests that AD may simply be "high-IQ autism" and that separate names for the disorders may not be warranted. The relation of these findings to theories of autism and AD are discussed.

Asperger syndrome and high-functioning autism

This paper reviews the history of Asperger syndrome (AS) and high-functioning autism (HFA), current diagnostic concepts and criteria, some controversial diagnostic issues, epidemiology, background factors, outcome, and intervention guidelines.

Boys with Asperger's disorder, exceptional verbal intelligence, tics, and clumsiness

Five boys with both Asperger's disorder and Tourette syndrome, exceptional verbal intelligence, and clumsiness are reported. Each presented at early elementary school age with a prominent complaint of social difficulties with peers. History was notable for a flapping stereotypy and the neurological examination revealed motor and/or vocal tics and numerous motor soft signs. Highly specialized interests were characteristics. Language prosody and/or pragmatics was impaired. Despite exceptional verbal intelligence, the children were not, according to their teachers and parents, faring well either socially or academically. Motor difficulties, manifested psychometrically as a significant performance IQ disadvantage, interfered with school performance and social adjustment. Tics, although not noted by parents in the clinical history, compounded their social difficulties. Asperger's disorder in these highly verbal children overlaps with pervasive developmental disorder (PDD) on account of the socioemotional difficulties and stereotypies seen in both. Asperger's disorder and Tourette syndrome overlap in these children on account of the tics. Finally, Asperger's disorder and the right-hemisphere-based learning disorders overlap on account of the visuoperceptual and attentional deficits that can occur in both.

Pedantic speaking style differentiates Asperger syndrome from high-functioning autism

Asperger syndrome (AS) is a pervasive developmental disorder recently introduced as a new diagnostic category in the ICD-10 and the DSM-IV. Along with motor clumsiness, pedantic speech has been proposed as a clinical feature of AS. However, few attempts have been made to define and measure this symptom. We studied 17 patients with AS (ICD-10; 14 male, 3 female; mean age 16.4 years, mean full-scale IQ 97) and compared them with a control group of 13 patients with normal-intelligence autism or high-functioning autism (HFA) (ICD-10/DSM-III-R; 12 male, 1 female; mean age 15.5 years, mean full-scale IQ 81.2). An operational definition of pedantic speech was formulated and a rating scale devised. 13 (76%) of the AS patients were rated as pedantic compared to 4 (31%) of the HFA group (chi 2 = 6.3; p = .01). Results suggest that pedantic speech is common in AS and may help differentiate AS from high-functioning autism.

Asperger syndrome associated with Steinert's myotonic dystrophy

Steinert's myotonic dystrophy was diagnosed in a 10-year-old girl with Asperger syndrome. This form of myotonic dystrophy is one of a growing list of genetic diseases that can be diagnosed by analysis of a gene with trinucleotide repeats that may expand. The patient has the largest such expansion known within her pedigree. She has many of the psychological deficits that have been reported in adult-onset myotonic dystrophy. This is the first known report of an association of this disorder with Asperger syndrome. Recently Moebius syndrome has been found in association with disorders of the autistic spectrum; physicians practicing developmental medicine should now also consider Steinert's myotonic dystrophy when evaluating children with facial diplegia.

Comparison of Asperger syndrome and high-functioning autistic children on a test of motor impairment

Compared the motor impairment levels of Asperger syndrome and high functioning autistic children using a standardized test, the Test of Motor Impairment-Henderson Revision. The two groups did not differ on either total or subscale impairment scores. Intelligence level was negatively correlated with motor impairment although the relationship was mostly accounted for by the Asperger children. There was considerable variability within both clinical groups but 50% of Asperger children and 67% of autistic children showed a clinically significant level of motor impairment. Results offer no support for clumsiness as a diagnostically differentiating feature of these disorders.

A preliminary study of right hemisphere cognitive deficits and impaired social judgments among young people with Asperger syndrome

Seven children and young adults with definite signs of Asperger syndrome were administered a battery of tests designed to test: intelligence; left and right cerebral hemisphere functioning; ability to discriminate eye gaze; and social judgment. The subjects revealed a non significant tendency to have a higher verbal IQ than visual IQ; and their right hemisphere functioning seemed impaired. They were also poorer at discriminating eye gaze and revealed difficulties in making hypothetical social judgments. The data are considered with reference to Rourke's (1988) work on non-verbal learning disabilities together with the ideas of Tantam (1992) on the "social gaze response" and Baron-Cohen's (1993) Eye-Detection Detector model. The possible links between social judgment and theory of mind (Frith, 1991) are briefly explored.

Is clumsiness a marker for Asperger syndrome?

Although Asperger syndrome (AS) has been included in the ICD-10 as a distinct category within the pervasive developmental disorders, it is still unclear to what extent it differs from normal-intelligence autism (high-functioning autism; HFA). Persons with AS are said to be particularly clumsy. To test the hypothesis that clumsiness can reliably distinguish AS from autism, the present authors compared 11 patients with AS (ICD-10; 10 males; mean age, 13.6 years; mean IQ, 98) with nine patients with HFA (ICD-10/DSM-III-R; eight males; mean age, 12.9 years; mean IQ, 84). Clumsiness was assessed by the Bruininks-Oseretsky test. Both groups showed problems with coordination and the distribution of standard scores was virtually identical. This suggests that motor clumsiness, as measured by tests of coordination, may not reliably distinguish AS from HFA. However, qualitative differences may occur between the two groups in the manner in which movements are performed. Further research with larger samples may elicit differences into the pattern of motor deficits that occur in autism and AS.

Three siblings with Asperger syndrome: A family case study

Reports of multiple incidence of Asperger syndrome have suggested links between Asperger syndrome and autism. In this case study, we describe three siblings with Asperger syndrome based on the ICD-10 criteria. There was no family history of mental retardation or of autism. We propose that in some families, Asperger syndrome may occur as a distinct clinical entity and show no overlap with autism.

Classification of pervasive developmental disorders: some concepts and practical considerations

Classifications have to meet a variety of purposes. Clinical and research needs are different and there is much to be said for separate clinical and research schemes. Care is needed to ensure that classifications provide an appropriate medium for teaching about diagnosis and do not cause difficulties when used as a "passport" to resources. Principles of classification are considered in relation to the need to take course, as well as symptomatology, into account, and with respect to the neuropsychiatric interface. The value of a multiaxial approach is noted. The pros and cons of autism and pervasive developmental disorders (PDD) as an overall descriptive term, of lumping or splitting, and of different choices with respect to PDD subcategories are discussed.